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1.
Dalton Trans ; 53(33): 14028-14036, 2024 Aug 20.
Article de Anglais | MEDLINE | ID: mdl-39105635

RÉSUMÉ

A novel MOF named [Zn2(L)(DMF)] was synthesized using solvothermal methods from the reaction of the new linker (4,4',4''-(4,4',4''-(benzene-1,3,5-triyltris(methylene))tris(3,5-dimethyl-1H-pyrazole-4,1-diyl))tribenzoic acid) and Zn(NO3)2·6H2O. This new MOF was characterized by means of different techniques: powder X-ray diffraction, N2 adsorption and desorption isotherms, thermogravimetric analysis, and scanning electron microscopy. Furthermore, suitable crystals were obtained, which allowed us to perform the X-Ray structure determination of this MOF. The capability of these new MOF to adsorb CO2 at different temperatures was measured and its isosteric enthalpy of adsorption was calculated. The novel MOF shows an uncommon node composed of a Zn3(-COO)6(DMF)2, and the asymmetric unit contains one crystallographically independent linker, one DMF molecule, and two Zn atoms. The [Zn2(L)(DMF)] MOF is a microporous material with high crystallinity and stability up to 250 °C. The multiple nitrogenated pyrazole linkers in its framework enhance its CO2 adsorption capabilities. This material exhibits a low CO2 isosteric enthalpy of adsorption (Hads), comparable to previously reported values for similar nitrogenated materials. All the observed CO2 adsorption capacities were further supported by DFT calculations.

2.
Bol. latinoam. Caribe plantas med. aromát ; 23(1): 152-159, ene. 2024. graf
Article de Anglais | LILACS | ID: biblio-1554187

RÉSUMÉ

Medicinal plants are used to cure diseases, and their replacement is frequent and affects public health. The genus Baccharis has representatives within the medicinal flora of Argentina, although the replacement of the species of this genus known under the vulgar name of "carqueja" by Baccharis spicata has been detected i n herbalists or markets of herbal products. The genotoxic safety of this species has been established in previous work of our group. The aim of this study was to evaluate the antiviral activity of an infusion made from B. spicata leaves against hepatitis B virus with the HepG2.2.15 cellular system and to determine cytotoxicity in HepG2.2,15, A549 and Vero cell lines. Infusion of B. spicata was active to inhibit HBV replication with an EC 50 of 22.54 µg/mL and a CC 50 of 190 µg/mL.


Las plantas medicinales son empleadas para la cura de enfermedades, y su sustituc ión es frecuente y afecta a la salud pública. El género Baccharis posee representantes dentro de la flora medicinal de Argentina, aunque se ha detectado la sustitución de las especies de dicho género conocidas bajo el nombre vulgar de "carqueja" por Baccha ris spicata en herboristerías o mercados de productos herb arios . Se ha establecido la seguridad genotóxica de esta especie en trabajos previos de nuestro grupo. Este estudio buscó evaluar la actividad antiviral de una infusión elaborada a partir de hojas de B. spicata frente al virus de la hepatitis B con el sistema celular HepG2.2.15 y determinar la citotoxicidad en las líneas celulares HepG2.2.15, A549 y Vero. La infusión de B. spicata fue activa para inhibir la replicación del virus con un EC 50 de 22.54 µg/mL y un CC 50 de 190 µg/mL.


Sujet(s)
Antiviraux/administration et posologie , Extraits de plantes/administration et posologie , Baccharis/composition chimique , Hépatite B/traitement médicamenteux , Antiviraux/pharmacologie , Réplication virale/effets des médicaments et des substances chimiques , Extraits de plantes/pharmacologie , Lignée cellulaire/effets des médicaments et des substances chimiques , Virus de l'hépatite B/effets des médicaments et des substances chimiques , Feuilles de plante , Asteraceae , Médecine traditionnelle
3.
J Pediatr ; 264: 113765, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37778410

RÉSUMÉ

OBJECTIVE: To describe the blood pressure outcomes of infants admitted to the neonatal intensive care unit (NICU) with idiopathic (nonsecondary) hypertension (HTN) who were discharged on antihypertensive therapy. STUDY DESIGN: Retrospective, multicenter study of 14 centers within the Pediatric Nephrology Research Consortium. We included all infants with a diagnosis of idiopathic HTN discharged from the NICU on antihypertensive treatment. The primary outcome was time to discontinuation of antihypertensive therapy, grouped into (≤6 months, >6 months to 1 year, and >1 year). Comparisons between groups were made with χ2 tests, Fisher's exact tests, and ANOVA. RESULTS: Data from 118 infants (66% male) were included. Calcium channel blockers were the most prescribed class of antihypertensives (56%) in the cohort. The percentages remaining on antihypertensives after NICU discharge were 60% at 6 months, 26% at 1 year, and 7% at 2 years. Antenatal steroid treatment was associated with decreased likelihood of antihypertensive therapy >1 year after discharge. CONCLUSIONS: This multicenter study reports that most infants admitted to the NICU diagnosed with idiopathic HTN will discontinue antihypertensive treatment by 2 years after NICU discharge. These data provide important insights into the outcome of neonatal HTN, but should be confirmed prospectively.


Sujet(s)
Hypertension artérielle , Maladies néonatales , Néphrologie , Grossesse , Nouveau-né , Nourrisson , Enfant , Humains , Mâle , Femelle , Unités de soins intensifs néonatals , Antihypertenseurs/usage thérapeutique , Études rétrospectives , Pression sanguine , Hypertension artérielle/diagnostic , Hypertension artérielle/traitement médicamenteux
4.
Kidney Med ; 5(11): 100722, 2023 Nov.
Article de Anglais | MEDLINE | ID: mdl-37965485

RÉSUMÉ

Rationale & Objective: PRESERVE seeks to provide new knowledge to inform shared decision-making regarding blood pressure (BP) management for pediatric chronic kidney disease (CKD). PRESERVE will compare the effectiveness of alternative strategies for monitoring and treating hypertension on preserving kidney function; expand the National Patient-Centered Clinical Research Network (PCORnet) common data model by adding pediatric- and kidney-specific variables and linking electronic health record data to other kidney disease databases; and assess the lived experiences of patients related to BP management. Study Design: Multicenter retrospective cohort study (clinical outcomes) and cross-sectional study (patient-reported outcomes [PROs]). Setting & Participants: PRESERVE will include approximately 20,000 children between January 2009-December 2022 with mild-moderate CKD from 15 health care institutions that participate in 6 PCORnet Clinical Research Networks (PEDSnet, STAR, GPC, PaTH, CAPRiCORN, and OneFlorida+). The inclusion criteria were ≥1 nephrologist visit and ≥2 estimated glomerular filtration rate (eGFR) values in the range of 30 to <90 mL/min/1.73 m2 separated by ≥90 days without an intervening value ≥90 mL/min/1.73 m2 and no prior dialysis or kidney transplant. Exposures: BP measurements (clinic-based and 24-hour ambulatory BP); urine protein; and antihypertensive treatment by therapeutic class. Outcomes: The primary outcome is a composite event of a 50% reduction in eGFR, eGFR of <15 mL/min/1.73 m2, long-term dialysis or kidney transplant. Secondary outcomes include change in eGFR, adverse events, and PROs. Analytical Approach: Longitudinal models for dichotomous (proportional hazards or accelerated failure time) and continuous (generalized linear mixed models) clinical outcomes; multivariable linear regression for PROs. We will evaluate heterogeneity of treatment effect by CKD etiology and degree of proteinuria and will examine variation in hypertension management and outcomes based on socio-demographics. Limitations: Causal inference limited by observational analyses. Conclusions: PRESERVE will leverage the PCORnet infrastructure to conduct large-scale observational studies that address BP management knowledge gaps for pediatric CKD, focusing on outcomes that are meaningful to patients. Plain-Language Summary: Hypertension is a major modifiable contributor to loss of kidney function in chronic kidney disease (CKD). The purpose of PRESERVE is to provide evidence to inform shared decision-making regarding blood pressure management for children with CKD. PRESERVE is a consortium of 16 health care institutions in PCORnet, the National Patient-Centered Clinical Research Network, and includes electronic health record data for >19,000 children with CKD. PRESERVE will (1) expand the PCORnet infrastructure for research in pediatric CKD by adding kidney-specific variables and linking electronic health record data to other kidney disease databases; (2) compare the effectiveness of alternative strategies for monitoring and treating hypertension on preserving kidney function; and (3) assess the lived experiences of patients and caregivers related to blood pressure management.

5.
J Head Trauma Rehabil ; 38(3): E186-E194, 2023.
Article de Anglais | MEDLINE | ID: mdl-36730991

RÉSUMÉ

OBJECTIVE: The goal of this study is to describe national trends in inpatient rehabilitation facility (IRF) discharges for the most severely disabled cohort of patients with traumatic brain injury (TBI). METHODS: Data from the Uniform Data System for Medical Rehabilitation for patients discharged from an IRF between January 1, 2002, and December 31, 2017, with a diagnosis of TBI and an admission Functional Independence Measure of 18, the lowest possible score, were obtained and analyzed. RESULTS: Of the 252 112 patients with TBI discharged during the study period, 10 098 met the study criteria. From 2002 to 2017, the number of patients with an IRF admission Functional Independence Measure of 18 following TBI discharged from IRFs annually decreased from 649 to 488, modeled by a negative regression (coefficient = -2.97; P = .001), and the mean age (SD) increased from 43.0 (21.0) to 53.7 (21.3) years (coefficient = 0.70; P < .001). During the study period, the number of patients with the most severe disability on admission to IRF who were discharged annually as a proportion of total patients with TBI decreased from 5.5% to 2.5% (odds ratio = 0.95; P < .001) and their mean length of stay decreased from 41.5 (36.2) to 29.3 (24.9) days (coefficient = -0.83; P < .001]. CONCLUSION: The number and proportion of patients with the most severe disability on IRF admission following TBI who are discharged from IRFs is decreasing over time. This may represent a combination of primary prevention, early mortality due to withdrawal of life-sustaining treatment, alternative discharge dispositions, or changes in admitting and reimbursement practices. Furthermore, there has been a decrease in the duration of IRF level care for these individuals, which could ultimately lead to poorer functional outcomes, particularly given the importance of specialized rehabilitative care in this population.


Sujet(s)
Lésions traumatiques de l'encéphale , Personnes handicapées , Humains , Patients hospitalisés , Centres de rééducation et de réadaptation , Récupération fonctionnelle , Durée du séjour , Sortie du patient , Études rétrospectives , Résultat thérapeutique
6.
J Racial Ethn Health Disparities ; 10(1): 56-63, 2023 Feb.
Article de Anglais | MEDLINE | ID: mdl-35060084

RÉSUMÉ

To assess the presence of racial disparity during the COVID-19 pandemic, the New Mexico Department of Health (NMDOH) sought to compare the case rate and risk of hospitalization between persons of American Indian and Alaska Native (AI/AN) race and persons of other races in New Mexico from March 1 through September 30, 2020. Using NMDOH COVID-19 surveillance data, age-standardized COVID-19 case and hospitalization risks were compared between adults (≥ 18 years old) of AI/AN and other races. We compared age, sex, and comorbidities between hospitalized adults of AI/AN and other races. Among AI/AN persons, age-standardized COVID-19 case and hospitalization risks were 3.7 (95% CI 3.6-3.8) and 10.5 (95% CI 9.8-11.2) times as high as persons of other races. Hospitalized AI/AN patients had higher proportions of diabetes mellitus (48% vs. 33%, P < 0.0001) and chronic liver disease (8% vs. 5%, P = 0.0004) compared to hospitalized patients of other races. AI/AN populations have disproportionately higher risk of COVID-19 hospitalization compared to other races in New Mexico. By identifying etiologic factors that contribute to inequity, public health partners can implement culturally appropriate health interventions to mitigate disease severity within AI/AN communities.


Sujet(s)
Autochtones d'Alaska , COVID-19 , Indiens d'Amérique Nord , Humains , Adulte , Jeune adulte , Adolescent , Population d'origine amérindienne , Nouveau Mexique/épidémiologie , Pandémies , Hospitalisation
9.
Microb Genom ; 8(5)2022 05.
Article de Anglais | MEDLINE | ID: mdl-35584008

RÉSUMÉ

Genomics has set the basis for a variety of methodologies that produce high-throughput datasets identifying the different players that define gene regulation, particularly regulation of transcription initiation and operon organization. These datasets are available in public repositories, such as the Gene Expression Omnibus, or ArrayExpress. However, accessing and navigating such a wealth of data is not straightforward. No resource currently exists that offers all available high and low-throughput data on transcriptional regulation in Escherichia coli K-12 to easily use both as whole datasets, or as individual interactions and regulatory elements. RegulonDB (https://regulondb.ccg.unam.mx) began gathering high-throughput dataset collections in 2009, starting with transcription start sites, then adding ChIP-seq and gSELEX in 2012, with up to 99 different experimental high-throughput datasets available in 2019. In this paper we present a radical upgrade to more than 2000 high-throughput datasets, processed to facilitate their comparison, introducing up-to-date collections of transcription termination sites, transcription units, as well as transcription factor binding interactions derived from ChIP-seq, ChIP-exo, gSELEX and DAP-seq experiments, besides expression profiles derived from RNA-seq experiments. For ChIP-seq experiments we offer both the data as presented by the authors, as well as data uniformly processed in-house, enhancing their comparability, as well as the traceability of the methods and reproducibility of the results. Furthermore, we have expanded the tools available for browsing and visualization across and within datasets. We include comparisons against previously existing knowledge in RegulonDB from classic experiments, a nucleotide-resolution genome viewer, and an interface that enables users to browse datasets by querying their metadata. A particular effort was made to automatically extract detailed experimental growth conditions by implementing an assisted curation strategy applying Natural language processing and machine learning. We provide summaries with the total number of interactions found in each experiment, as well as tools to identify common results among different experiments. This is a long-awaited resource to make use of such wealth of knowledge and advance our understanding of the biology of the model bacterium E. coli K-12.


Sujet(s)
Escherichia coli K12 , Escherichia coli , Escherichia coli/génétique , Escherichia coli K12/génétique , Escherichia coli K12/métabolisme , Régulation de l'expression des gènes bactériens , Opéron/génétique , Reproductibilité des résultats
10.
Diabetes Care ; 45(7): 1558-1567, 2022 07 07.
Article de Anglais | MEDLINE | ID: mdl-35621712

RÉSUMÉ

OBJECTIVE: Guidelines advocate against tight glycemic control in older nursing home (NH) residents with advanced dementia (AD) or limited life expectancy (LLE). We evaluated the effect of deintensifying diabetes medications with regard to all-cause emergency department (ED) visits, hospitalizations, and death in NH residents with LLE/AD and tight glycemic control. RESEARCH DESIGN AND METHODS: We conducted a national retrospective cohort study of 2,082 newly admitted nonhospice veteran NH residents with LLE/AD potentially overtreated for diabetes (HbA1c ≤7.5% and one or more diabetes medications) in fiscal years 2009-2015. Diabetes treatment deintensification (dose decrease or discontinuation of a noninsulin agent or stopping insulin sustained ≥7 days) was identified within 30 days after HbA1c measurement. To adjust for confounding, we used entropy weights to balance covariates between NH residents who deintensified versus continued medications. We used the Aalen-Johansen estimator to calculate the 60-day cumulative incidence and risk ratios (RRs) for ED or hospital visits and deaths. RESULTS: Diabetes medications were deintensified for 27% of residents. In the subsequent 60 days, 28.5% of all residents were transferred to the ED or acute hospital setting for any cause and 3.9% died. After entropy weighting, deintensifying was not associated with 60-day all-cause ED visits or hospitalizations (RR 0.99 [95% CI 0.84, 1.18]) or 60-day mortality (1.52 [0.89, 2.81]). CONCLUSIONS: Among NH residents with LLE/AD who may be inappropriately overtreated with tight glycemic control, deintensification of diabetes medications was not associated with increased risk of 60-day all-cause ED visits, hospitalization, or death.


Sujet(s)
Diabète , Anciens combattants , Sujet âgé , Service hospitalier d'urgences , Hémoglobine glyquée , Hospitalisation , Humains , Maisons de repos , Études rétrospectives
11.
Am J Health Syst Pharm ; 79(15): 1296-1300, 2022 07 22.
Article de Anglais | MEDLINE | ID: mdl-35451022

RÉSUMÉ

PURPOSE: The aim of this review was to build upon previous literature describing the maximum duration for which refrigerated medications can tolerate room temperature excursions while maintaining stability and potency. METHODS: During a 12-month period ending in June 2021, the prescribing information and published monographs from multiple pharmacy compendia were reviewed for all medications and biologic products approved by the US Food and Drug Administration (FDA) for human use since January 2000. Products that were subsequently withdrawn from the US market were excluded. When temperature excursion data was unavailable in published form, product manufacturers were surveyed via telephone and/or email. Acceptable storage information for all products for which storage is recommended at temperatures below room temperature (20-25 °C [68-77 °F]) was compiled and arranged in tabular format. RESULTS: Of the 705 products or formulations approved by FDA during the predefined time period, 246 were identified as requiring storage at temperatures below room temperature. After review of available prescribing information and manufacturer communications, if applicable, acceptable periods of excursion to temperatures at room temperature or higher were identified for 214 products (87%). CONCLUSION: Information related to acceptable periods of room temperature excursion was compiled for a total of 214 products approved for US distribution since 2000. The included tables may increase patient safety and decrease medication loss or related expenditures.


Sujet(s)
Services pharmaceutiques , Stabilité de médicament , Stockage de médicament , Humains , Préparations pharmaceutiques , Température , États-Unis , Food and Drug Administration (USA)
12.
J Pediatr ; 246: 154-160.e1, 2022 07.
Article de Anglais | MEDLINE | ID: mdl-35351534

RÉSUMÉ

OBJECTIVES: To determine whether youth with white coat hypertension on initial ambulatory blood pressure monitoring (ABPM) continue to demonstrate the same pattern on repeat ABPM. STUDY DESIGN: Retrospective longitudinal cohort study of patients referred for high blood pressure (BP) and diagnosed with white coat hypertension by ABPM who had follow-up ABPM 0.5-4.6 years later at 11 centers in the Pediatric Nephrology Research Consortium. We classified ABPM phenotype using the American Heart Association guidelines. At baseline, we classified those with hypertensive BP in the clinic as "stable white coat hypertension," and those with normal BP as "intermittent white coat hypertension." We used multivariable generalized linear mixed effect models to estimate the association of baseline characteristics with abnormal ABPM phenotype progression. RESULTS: Eighty-nine patients met the inclusion criteria (median age, 13.9 years; 78% male). Median interval time between ABPM measurements was 14 months. On follow-up ABPM, 61% progressed to an abnormal ABPM phenotype (23% ambulatory hypertension, 38% ambulatory prehypertension). Individuals age 12-17 years and those with stable white coat hypertension had greater proportions progressing to either prehypertension or ambulatory hypertension. In the multivariable models, baseline wake systolic BP index ≥0.9 was significantly associated with higher odds of progressing to ambulatory hypertension (OR 3.07, 95% CI 1.02-9.23). CONCLUSIONS: The majority of the patients with white coat hypertension progressed to an abnormal ABPM phenotype. This study supports the 2017 American Academy of Pediatrics Clinical Practice Guideline's recommendation for follow-up of ABPM in patients with white coat hypertension.


Sujet(s)
Hypertension artérielle , Néphrologie , Pédiatrie , Préhypertension , Hypertension de la blouse blanche , Adolescent , Pression sanguine/physiologie , Surveillance ambulatoire de la pression artérielle , Enfant , Femelle , Humains , Hypertension artérielle/complications , Études longitudinales , Mâle , Études rétrospectives , Hypertension de la blouse blanche/diagnostic
13.
J Thromb Haemost ; 20(7): 1712-1719, 2022 07.
Article de Anglais | MEDLINE | ID: mdl-35325493

RÉSUMÉ

BACKGROUND: Platelet α-granule biogenesis in precursor megakaryocytes is critically dependent on VPS33B and VPS16B, as demonstrated by the platelet α-granule deficiency seen in the rare multisystem disorder arthrogryposis, renal dysfunction, and cholestasis (ARC) syndrome associated with biallelic pathogenic variants in VPS33B and VIPAS39 (encoding VPS16B). VPS33B and VPS16B are ubiquitously expressed proteins that are known to interact and play key roles in protein sorting and trafficking between subcellular locations. However, there remain significant gaps in our knowledge of the nature of these interactions in primary cells from patients with ARC syndrome. OBJECTIVES: To use primary cells from patients with ARC syndrome to better understand the interactions and roles of VPS33B and VPS16B in platelets and precursor megakaryocytes. PATIENTS/METHODS: The proband and his male sibling were clinically suspected to have ARC syndrome. Confirmatory genetic testing and platelet phenotyping, including electron microscopy and protein expression analysis, was performed with consent in a research setting. RESULTS: We describe the first case of ARC syndrome identified in Costa Rica, associated with a novel homozygous nonsense VPS33B variant that is linked with loss of expression of both VPS33B and VPS16B in platelets. CONCLUSION: These results indicate that stable expression of VPS16B in platelets, their precursor megakaryocytes, and other cells is dependent on VPS33B. We suggest that systematic evaluation of primary cells from patients with a range of VPS33B and VIPAS39 variants would help to elucidate the interactions and functions of these proteins.


Sujet(s)
Arthrogrypose , Cholestase , Arthrogrypose/diagnostic , Arthrogrypose/génétique , Arthrogrypose/métabolisme , Plaquettes/métabolisme , Cholestase/diagnostic , Cholestase/génétique , Cholestase/métabolisme , Humains , Mâle , Insuffisance rénale , Fratrie , Protéines du transport vésiculaire/génétique , Protéines du transport vésiculaire/métabolisme
15.
Biota Neotrop. (Online, Ed. ingl.) ; 22(spe): e20221394, 2022. graf
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1394014

RÉSUMÉ

Abstract speciesLink is a large-scale biodiversity information portal that exists thanks to a broad collaborative network of people and institutions. CRIA's involvement with the scientific community of Brazil and other countries is responsible for the significant results achieved, currently reaching more than 15 million primary biodiversity data records, 95% of which are associated with preserved specimens and about 25% with high-quality digital images. The network provides data on over 200,000 species, of which over 110,000 occur in Brazil. This article describes thematic networks within speciesLink, as well as some of the most useful tools developed. The importance and contributions of speciesLink are outlined, as are concerns about securing stable budgetary support for such biodiversity data e-infrastructures. Here we review the value of speciesLink as a major source of biodiversity information for research, education, informed decision-making, policy development, and bioeconomy.


Resumo speciesLink é um portal de informações em larga escala sobre biodiversidade, que existe graças a uma ampla rede colaborativa de pessoas e instituições. O envolvimento do CRIA com a comunidade científica do Brasil e de outros países é responsável pelos resultados expressivos alcançados, atingindo atualmente mais de 15 milhões de registros de dados primários de biodiversidade, sendo 95% associados a espécimes preservados e cerca de 25% a imagens digitais de alta qualidade. A rede fornece dados sobre mais de 200.000 espécies, das quais mais de 110.000 ocorrem no Brasil. Este artigo descreve as redes temáticas do speciesLink, bem como algumas das ferramentas mais úteis desenvolvidas. A importância e as contribuições do speciesLink são destacadas, assim como as preocupações em garantir um apoio financeiro estável para e-infraestruturas de dados sobre biodiversidade. Aqui revisamos o valor do speciesLink como uma das principais fontes de informação sobre biodiversidade para pesquisa, educação, tomada de decisão, desenvolvimento de políticas e bioeconomia.

17.
J Infect Dis ; 224(10): 1684-1689, 2021 11 22.
Article de Anglais | MEDLINE | ID: mdl-34491360

RÉSUMÉ

The New Mexico Department of Health (NMDOH) conducted a matched case-control study to compare 315 persons (cases) with and 945 persons (controls) without severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) secondary detection (ie, positive SARS-CoV-2 test ≥90 days after first detection as of December 10, 2020). Compared with controls, cases had greater odds of higher SARS-CoV-2 testing frequency (adjusted odds ratio [aOR] = 1.2), being female (aOR = 1.6), being non-Hispanic American Indian/Alaska Native (aOR = 2.3), having diabetes mellitus (aOR = 1.8), and residing and/or working in detention and/or correctional facilities (aOR = 4.7). Diagnostic tools evaluating infectiousness at secondary detection are urgently needed to inform infection control practices.


Sujet(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnostic , Dépistage de la COVID-19 , Études cas-témoins , Femelle , Humains , Mâle , Nouveau Mexique/épidémiologie
18.
Dalton Trans ; 50(8): 2880-2890, 2021 Feb 28.
Article de Anglais | MEDLINE | ID: mdl-33544103

RÉSUMÉ

Metal-organic frameworks (MOFs) have attracted significant attention as sorbents due to their high surface area, tunable pore volume and pore size, coordinatively unsaturated metal sites, and ability to install desired functional groups by post-synthetic modification. Herein, we report three new MOFs with pillar-paddlewheel structures that have been synthesized solvothermally from the mixture of the carboxylate-pyrazole flexible linker (H2L), 4,4-bipyridine (BPY)/triethylenediamine (DABCO), and Zn(ii)/Cu(ii) ions. The MOFs obtained, namely [ZnII(L)BPY], [CuII(L)BPY], and [CuII(L)DABCO], exhibit two-fold interpenetration and dinuclear paddle-wheel nodes. The Zn(ii)/Cu(ii) cations are coordinated by two equatorial L linkers that result in two-dimensional sheets which in turn are pillared by BPY or DABCO in the perpendicular direction to obtain a neutral three-dimensional framework that shows one-dimensional square channels. The three pillar-layered MOFs were characterized as microporous materials showing high crystalline stability after activation at 120 °C and CO2 adsorption. All MOFs contain uncoordinated Lewis basic pyrazole nitrogen atoms in the framework which have an affinity toward CO2 and hence could potentially serve as CO2 adsorption material. The CO2 uptake capacity was initially enhanced by replacing Zn with Cu and then replacing the pillar, going from BPY to DABCO. Overall, all the MOFs exhibit low isosteric heat (Qst) of adsorption which signifies an advantage due to the energy required for the adsorption and regeneration processes.

19.
Langmuir ; 37(8): 2575-2585, 2021 Mar 02.
Article de Anglais | MEDLINE | ID: mdl-33587633

RÉSUMÉ

We consider the coupled process of phase separation and dewetting of metal alloys of nanoscale thickness deposited on solid substrates. The experiments involve applying nanosecond laser pulses that melt the Ag40Ni60 alloy films in two setups: either on thin supporting membranes or on bulk substrates. These two setups allow for extracting both temporal and spatial scales on which the considered processes occur. The theoretical model involves a longwave version of the Cahn-Hilliard formulation used to describe spinodal decomposition, coupled with an asymptotically consistent longwave-based description of dewetting that occurs due to destabilizing interactions between the alloy and the substrate, modeled using the disjoining pressure approach. Careful modeling, combined with linear stability analysis and fully nonlinear simulations, leads to results consistent with the experiments. In particular, we find that the two instability mechanisms occur concurrently, with the phase separation occurring faster and on shorter temporal scales. The modeling results show a strong influence of the temperature dependence of relevant material properties, implying that such a dependence is crucial for the understanding of the experimental findings. The agreement between theory and experiment suggests the utility of the proposed theoretical approach in helping to develop further experiments directed toward formation of metallic alloy nanoparticles of desired properties.

20.
Pediatr Nephrol ; 36(6): 1407-1426, 2021 06.
Article de Anglais | MEDLINE | ID: mdl-32995920

RÉSUMÉ

The last decade was crucial for our understanding of the renin-angiotensin-aldosterone system (RAAS) as a two-axis, counter-regulatory system, divided into the classical axis, formed by angiotensin-converting enzyme (ACE), angiotensin II (Ang II), and the angiotensin type 1 receptor (AT1R), and the alternative axis comprising angiotensin-converting enzyme 2 (ACE2), angiotensin-(1-7) (Ang-(1-7)), and the Mas receptor. Breakthrough discoveries also took place, with other RAAS endopeptides being described, including alamandine and angiotensin A. In this review, we characterize the two RAAS axes and the role of their components in pediatric kidney diseases, including childhood hypertension (HTN), pediatric glomerular diseases, congenital abnormalities of the kidney and urinary tract (CAKUT), and chronic kidney disease (CKD). We also present recent findings on potential interactions between the novel coronavirus, SARS-CoV-2, and components of the RAAS, as well as potential implications of coronavirus disease 2019 (COVID-19) for pediatric kidney diseases.


Sujet(s)
COVID-19/physiopathologie , Maladies du rein/physiopathologie , Système rénine-angiotensine/physiologie , Enfant , Humains
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