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1.
Rev. enferm. UERJ ; 32: e74792, jan. -dez. 2024.
Artículo en Inglés, Español, Portugués | LILACS-Express | LILACS | ID: biblio-1554732

RESUMEN

Objetivo: analisar as características e os desfechos obstétricos adversos em gestantes/puérperas infectadas pelo SARS-CoV-2 em serviço de referência. Método: série de casos retrospectiva entre gestantes com Covid-19 em um hospital universitário em Minas Gerais, Brasil, atendidas no serviço de 2020 a 2021, coletados em abril de 2022, empregando-se estatística descritiva para análise dos dados através do Statistical Package for the Social Science. Resultados: incluídas 26 gestantes, em sua maioria brancas, que tiveram como principais desfechos obstétricos adversos a internação em UTI (43,5%), parto prematuro (34,6%), dado reestratificado de semanas para dias para investigar o encurtamento da gestação, onde constatou-se média de 38,6 dias potenciais de gravidez perdidos dos 280 dias ideais, e ainda 15,4% evoluíram para óbito materno. Conclusão: o estudo proporcionou evidenciar a necessidade de vigilância e atenção às gestantes com foco nos principais desfechos adversos, podendo-se intervir em tempo oportuno para diminuir adversidades.


Objective: to analyze the characteristics and adverse obstetric outcomes in pregnant/puerperal women infected by SARS-CoV-2 at a reference service. Method: a retrospective case series conducted among pregnant women with Covid-19 in a university hospital from Minas Gerais, Brazil, treated at the service from 2020 to 2021. The cases were collected in April 2022 employing descriptive statistics for data analysis in the Statistical Package for the Social Science. Results: a total of 26 pregnant women were included, mostly white-skinned, whose main adverse obstetric outcomes were admission to the ICU (43.5%), premature birth (34.6%) and data restratified from weeks to days to investigate shortening of pregnancy, where a mean of 38.6 potential days of pregnancy were lost out of the ideal 280 days, and 15.4% resulted in maternal death. Conclusion: the study provided evidence of the need for surveillance and care for pregnant women with a focus on the main adverse outcomes, enabling timely intervention to reduce adversities.


Objetivo: analizar las características y resultados obstétricos adversos en gestantes/puérperas infectadas por SARS-CoV-2 en un servicio de referencia. Método: serie de casos retrospectiva entre gestantes con Covid-19 en un hospital universitario de Minas Gerais, Brasil, atendidas en el servicio de 2020 a 2021. Los datos se recolectaron en abril de 2022, se utilizó estadística descriptiva para analizar los datos mediante el Statistical Package for the Social Science. Resultados: se incluyeron 26 gestantes, la mayoría de raza blanca, cuyos principales resultados obstétricos adversos fueron ingreso a UCI (43,5%), parto prematuro (34,6%), dato reestratificado de semanas a días para investigar el acortamiento de la gestación, que arrojó como resultado un promedio de 38,6. Se comprobó que se perdieron en promedio 38,6 días potenciales de embarazo de los 280 días ideales, y muerte materna (15,4%). Conclusión: la evidencia que proporcionó el estudio indica que es necesario vigilar y atender a las gestantes enfocándose en los principales resultados adversos, lo que permite intervenir de forma oportuna para reducir adversidades.

2.
J. bras. nefrol ; 46(3): e20240023, July-Sept. 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1558252

RESUMEN

In the last few years, evidence from the Brazilian Registry of Bone Biopsy (REBRABO) has pointed out a high incidence of aluminum (Al) accumulation in the bones of patients with CKD under dialysis. This surprising finding does not appear to be merely a passive metal accumulation, as prospective data from REBRABO suggest that the presence of Al in bone may be independently associated with major adverse cardiovascular events. This information contrasts with the perception of epidemiologic control of this condition around the world. In this opinion paper, we discussed why the diagnosis of Al accumulation in bone is not reported in other parts of the world. We also discuss a range of possibilities to understand why bone Al accumulation still occurs, not as a classical syndrome with systemic signs of intoxication, as occurred it has in the past.


Nos últimos anos, evidências do Registro Brasileiro de Biópsia óssea (REBRABO) apontaram uma alta incidência de intoxicação por alumínio (Al) no tecido ósseo de pacientes com DRC em diálise. Essa surpreendente informação parece representar não apenas um acúmulo passivo deste metal, visto que dados prospectivos do REBRABO sugerem que a presença de Al no tecido ósseo pode estar independentemente relacionada a eventos cardiovasculares adversos maiores. Essas informações contrastam com a percepção mundial do controle epidemiológico dessa condição. Neste artigo de opinião, discutimos por que o diagnóstico de acúmulo ósseo de Al não é relatado em outras partes do mundo, e também discutimos uma gama de possibilidades para entender por que nós acreditamos que o acúmulo de Al no tecido ósseo ainda ocorre, não como se apresentava no passado, ou seja, como uma síndrome com sinais e sintomas sistêmicos de intoxicação.

3.
J. bras. nefrol ; 46(3): e20230175, July-Sept. 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1558256

RESUMEN

Abstract Introduction: Secondary hyperparathyroidism (SHPT) is one of the causes for inflammation in CKD. We assessed the impact of parathyroidectomy (PTX) on neutrophil-to-lymphocyte (N/L) and platelet-to-lymphocyte (P/L) ratios in SHPT patients. Methods: A total of 118 patients [hemodialysis (HD, n = 81), and transplant recipients (TX, n = 37)] undergoing PTX between 2015 and 2021 were analyzed. Results: There was a significant reduction in calcium and PTH levels in both groups, in addition to an increase in vitamin D. In the HD group, PTX did not alter N/L and P/L ratios. In the TX group, there was a reduction in N/L and P/L ratios followed by a significant increase in total lymphocyte count. Conclusion: N/L and P/L ratios are not reliable biomarkers of inflammation in SHPT patients undergoing PTX. Uremia, which induces a state of chronic inflammation in dialysis patients, and the use of immunosuppression in kidney transplant recipients are some of the confounding factors that prevent the use of this tool in clinical practice.


Resumo Introdução: O hiperparatireoidismo secundário (HPTS) é uma das causas de inflamação na DRC. Avaliamos o impacto da paratireoidectomia (PTX) nas relações neutrófilo/linfócito (N/L) e plaqueta/linfócito (P/L) em pacientes com HPTS. Métodos: Foram analisados 118 pacientes [hemodiálise (HD, n = 81) e transplantados (TX, n = 37)] submetidos à PTX entre 2015 e 2021. Resultados: Houve redução significativa de cálcio e PTH nos dois grupos, além de elevação de vitamina D. No grupo HD, a PTX não mudou as relações N/L e P/L. Já no grupo TX, houve redução nas relações N/L e P/L acompanhadas de elevação significativa do número de linfócitos totais. Conclusão: As relações N/L e P/L não são marcadores fidedignos de inflamação em pacientes com HPTS submetidos à PTX. A uremia, que induz um estado de inflamação crônica em pacientes dialíticos, e o uso de imunossupressão em pacientes transplantados renais são alguns dos fatores de confusão que impedem o uso dessa ferramenta na prática clínica.

4.
J Exp Pharmacol ; 16: 257-270, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39144251

RESUMEN

Background: The diuretic activity of the Cucumis dipsaceus leaf, which is used in indigenous medicine, has been claimed but has not yet undergone scientific evaluation. Objective: The objective of this study was to assess the diuretic activity of the aqueous and 80% methanol extracts derived from the leaves of Cucumis dipsaceus in rats. Methods: For the extraction process, the maceration technique was employed to obtain the aqueous and 80% methanol extracts from the Cucumis dipsaceus leaves. Male rats were then divided randomly into eight groups, with six rats in each group. These groups consisted of a negative control group, a positive control group, and three different groups for each extract at varying doses. The urine output volumes, the concentrations of urinary electrolytes (sodium, potassium, and chloride) and urinary pH, were measured and analysed to compare the results among the different groups. Results: Both the aqueous and 80% methanol extracts of Cucumis dipsaceus leaves demonstrated a significant increase in urinary output at doses of 200mg/kg body weight (p<0.01) and 400mg/kg body weight (p<0.001). When comparing the urinary electrolyte excretion with the negative control group, the groups treated with the 400mg/kg body weight dose of the aqueous extract showed significant differences in the urinary excretion of sodium (p<0.05), chloride (p<0.01), and K+ (p<0.01). Similarly, the urinary excretion of K+ and Cl- also exhibited significant differences at moderate doses (K+: p<0.01, Cl-: p<0.05) and the highest doses (both: p<0.01) of the 80% methanol extract. Furthermore, the highest doses of both the aqueous (p<0.01) and 80% methanol (p<0.01) extracts demonstrated significant differences in saluretic effect. Conclusion: Both crude extracts of C. dipsaceus leaves have significant diuretic activity, providing support for the traditional use of the plant as a diuretic agent.

5.
Front Neurosci ; 18: 1415576, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39145297

RESUMEN

Introduction: We previously reported that ATP1A3 c.823G>C (p.Ala275Pro) mutant causes varying phenotypes of alternative hemiplegia of childhood and rapid-onset dystonia-parkinsonism in the same family. This study aims to investigate the function of ATP1A3 c.823G>C (p.Ala275Pro) mutant at the cellular and zebrafish models. Methods: ATP1A3 wild-type and mutant Hela cell lines were constructed, and ATP1A3 mRNA expression, ATP1A3 protein expression and localization, and Na+-K+-ATPase activity in each group of cells were detected. Additionally, we also constructed zebrafish models with ATP1A3 wild-type overexpression (WT) and p.Ala275Pro mutant overexpression (MUT). Subsequently, we detected the mRNA expression of dopamine signaling pathway-associated genes, Parkinson's disease-associated genes, and apoptosisassociated genes in each group of zebrafish, and observed the growth, development, and movement behavior of zebrafish. Results: Cells carrying the p.Ala275Pro mutation exhibited lower levels of ATP1A3 mRNA, reduced ATP1A3 protein expression, and decreased Na+-K+-ATPase activity compared to wild-type cells. Immunofluorescence analysis revealed that ATP1A3 was primarily localized in the cytoplasm, but there was no significant difference in ATP1A3 protein localization before and after the mutation. In the zebrafish model, both WT and MUT groups showed lower brain and body length, dopamine neuron fluorescence intensity, escape ability, swimming distance, and average swimming speed compared to the control group. Moreover, overexpression of both wild-type and mutant ATP1A3 led to abnormal mRNA expression of genes associated with the dopamine signaling pathway and Parkinson's disease in zebrafish, and significantly upregulated transcription levels of bad and caspase-3 in the apoptosis signaling pathway, while reducing the transcriptional level of bcl-2 and the bcl-2/bax ratio. Conclusion: This study reveals that the p.Ala275Pro mutant decreases ATP1A3 protein expression and Na+/K+-ATPase activity. Abnormal expression of either wild-type or mutant ATP1A3 genes impairs growth, development, and movement behavior in zebrafish.

6.
Biol Res ; 57(1): 57, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39175101

RESUMEN

BACKGROUND: While calcium is known to play a crucial role in mammalian sperm physiology, how it flows in and out of the male gamete is not completely understood. Herein, we investigated the involvement of Na+/Ca2+ exchangers (NCX) in mammalian sperm capacitation. Using the pig as an animal model, we first confirmed the presence of NCX1 and NCX2 isoforms in the sperm midpiece. Next, we partially or totally blocked Ca2+ outflux (forward transport) via NCX1/NCX2 with different concentrations of SEA0400 (2-[4-[(2,5-difluorophenyl)methoxy]phenoxy]-5-ethoxyaniline; 0, 0.5, 5 and 50 µM) and Ca2+ influx (reverse transport) with SN6 (ethyl 2-[[4-[(4-nitrophenyl)methoxy]phenyl]methyl]-1,3-thiazolidine-4-carboxylate; 0, 0.3, 3 or 30 µM). Sperm were incubated under capacitating conditions for 180 min; after 120 min, progesterone was added to induce the acrosome reaction. At 0, 60, 120, 130, and 180 min, sperm motility, membrane lipid disorder, acrosome integrity, mitochondrial membrane potential (MMP), tyrosine phosphorylation of sperm proteins, and intracellular levels of Ca2+, reactive oxygen species (ROS) and superoxides were evaluated. RESULTS: Partial and complete blockage of Ca2+ outflux and influx via NCX induced a significant reduction of sperm motility after progesterone addition. Early alterations on sperm kinematics were also observed, the effects being more obvious in totally blocked than in partially blocked samples. Decreased sperm motility and kinematics were related to both defective tyrosine phosphorylation and mitochondrial activity, the latter being associated to diminished MMP and ROS levels. As NCX blockage did not affect the lipid disorder of plasma membrane, the impaired acrosome integrity could result from reduced tyrosine phosphorylation. CONCLUSIONS: Inhibition of outflux and influx of Ca2+ triggered similar effects, thus indicating that both forward and reverse Ca2+ transport through NCX exchangers are essential for sperm capacitation.


Asunto(s)
Calcio , Intercambiador de Sodio-Calcio , Capacitación Espermática , Animales , Masculino , Capacitación Espermática/efectos de los fármacos , Intercambiador de Sodio-Calcio/metabolismo , Intercambiador de Sodio-Calcio/efectos de los fármacos , Calcio/metabolismo , Porcinos , Espermatozoides/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Motilidad Espermática/efectos de los fármacos , Reacción Acrosómica/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos
7.
Vaccine X ; 19: 100531, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39157684

RESUMEN

Since 2022, three human cases of a novel H3N8 avian influenza virus infection have been reported in three provinces in China. Specific vaccines are important means of preparing for the potential influenza pandemic. Thus, H3N8 viruses [A/Henan/cnic410/2022 (HN410) and A/Changsha/1000/2022(CS1000)] were isolated from the infected patients as prototype viruses to develop candidate vaccine viruses (CVVs) using the reverse genetics (RG) technology. Five reassortant viruses with different HA and NA combinations were constructed based on the two viruses to get a high-yield and safe CVV. The results showed that all viruses had similar antigenicity but different growth characteristics. Reassortant viruses carrying NA from CS1000 exhibited better growth ability and NA enzyme activity than the ones carrying HN410 NA. Furthermore, the NA gene of CS1000 had one more potential N-glycosylation site at position 46 compared with HN410. The substitution of position 46 showed that adding or removing N-glycosylation sites to different reassortant viruses had different effects on growth ability. A reassortant virus carrying HN410 HA and CS1000 NA with high growth ability was selected as a CVV, which met the requirements for a CVV. These data suggest that different surface gene combinations and the presence or absence of potential N-glycosylation sites on position 46 in the NA gene affect the growth characteristics of H3N8 CVVs.

8.
Artículo en Inglés | MEDLINE | ID: mdl-39159387

RESUMEN

Confluent populations of the epithelial cell line, MDCK II, develop circumferential tight junctions joining adjacent cells to create a barrier to the paracellular movement of solutes and water. Treatment of MDCK II cell populations from the apical surface with 1 mM Na-caprate increased permeability to macromolecules (Leak Pathway) without increasing monolayer disruption or cell death. Graphical analysis of the apparent permeability versus solute Stokes radius for a size range of fluorescein-dextran species indicates apical 1 mM Na-caprate enhances Leak Pathway permeability by increasing the number of Leak Pathway openings without significantly affecting opening size. Na-caprate treatment did not alter the content of any tight junction protein examined. Treatment of MDCK II cell populations with apical 1 mM Na-caprate disrupted basal F-actin stress fibers and decreased the tortuosity of the tight junctions. Treatment of MDCK II cell populations with blebbistatin, a myosin ATPase inhibitor, alone had little effect on Leak Pathway permeability but synergistically increased Leak Pathway permeability when added with 1 mM Na-caprate. Na-caprate exhibited a similar ability to increase Leak Pathway permeability in wild type MDCK II cell monolayers and ZO-1 knockdown MDCK II cell monolayers but an enhanced ability to increase Leak Pathway permeability in monolayers of TOCA-1 knockout MDCK II cells. These results demonstrate that Na-caprate increases MDCK II cell population Leak Pathway permeability by increasing the number of Leak Pathway openings. This action is likely mediated by alterations in F-actin organization, primarily involving disruption of basal F-actin stress fibers.

9.
Natl Sci Rev ; 11(8): nwae242, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39165665

RESUMEN

Reproducing the outstanding selectivity achieved by biological ion channels in artificial channel systems can revolutionize applications ranging from membrane filtration to single-molecule sensing technologies, but achieving this goal remains a challenge. Herein, inspired by the selectivity filter structure of the KcsA potassium channel, we propose a design of biomimetic potassium nanochannels by functionalizing the wall of carbon nanotubes with an array of arranged carbonyl oxygen atoms. Our extensive molecular dynamics simulations show that the biomimetic nanochannel exhibits a high K+ permeation rate along with a high K+/Na+ selectivity ratio. The free energy calculations suggest that the low Na+ permeability is the result of the higher energy barrier for Na+ than K+ at the channel entrance and ion binding sites. In addition, reducing the number of ion binding sites leads to an increase in the permeation rate but a decrease in selectivity. These findings not only hold promise for the design of high-performance membranes but also help understand the mechanism of selective ion transport in biological ion channels.

10.
Nano Lett ; 24(32): 9839-9845, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39087826

RESUMEN

Hard carbon (HC) is a promising anode candidate for Na-ion batteries (NIBs) because of its excellent Na-storage performance, abundance, and low cost. However, a precise understanding of its Na-storage behavior remains elusive. Herein, based on the D2O/H2SO4-based TMS results collected on charged/discharged state HC electrodes, detailed Na-storage mechanisms (the Na-storage states and active sites in different voltage regions), specific SEI dynamic evolution process (formation, rupture, regeneration and loss), and irreversible capacity contribution (dead Na0, NaH, etc.) were elucidated. Moreover, by employing the online electrochemical mass spectrometry (OEMS) to monitor the gassing behavior of HC-Na half-cell during the overdischarging process, a surprising rehydrogen evolution reaction (re-HER) process at around 0.02 V vs Na+/Na was identified, indicating the occurrence of Na-plating above 0 V vs Na+/Na. Additionally, the typical fluorine ethylene carbonate (FEC) additive was demonstrated to reduce the accumulation of dead Na0 and inhibit the re-HER process triggered by plated Na.

11.
Nano Lett ; 24(32): 9832-9838, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39101565

RESUMEN

The surface of three-dimensional materials provides an ideal and versatile platform to explore quantum-confined physics. Here, we systematically investigate the electronic structure of Na-intercalated CrTe2, a van der Waals antiferromagnet, using angle-resolved photoemission spectroscopy and ab initio calculations. The measured band structure deviates from the calculation of bulk NaCrTe2 but agrees with that of ferromagnetic monolayer CrTe2. Consistently, we observe unexpected exchange splitting of the band dispersions, persisting well above the Néel temperature of bulk NaCrTe2. We argue that NaCrTe2 features a quantum-confined 2D ferromagnetic state in the topmost surface layer due to strong ferromagnetic correlation in the CrTe2 layer. Moreover, the exchange splitting and the critical temperature can be controlled by surface doping of alkali-metal atoms, suggesting the feasibility of tuning the surface ferromagnetism. Our work not only presents a simple platform for exploring tunable 2D ferromagnetism but also provides important insights into the quantum-confined low-dimensional magnetic states.

12.
Int J Hepatol ; 2024: 5852680, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39149542

RESUMEN

Background: Cirrhosis incidence in older adult patients has been increasing with limited data on their survival. This study is aimed at investigating the survival and disease progression in older adult patients with cirrhosis compared to younger patients. Methods: This is a retrospective single-center study. Patients aged above 50 with a confirmed diagnosis of cirrhosis based on biopsy, FibroSure test, splenomegaly, and low platelets < 120 × 109/L) or imaging findings including FibroScan were included. Patients with active substance abuse, transjugular intrahepatic portosystemic shunt (TIPS), prior spontaneous bacterial peritonitis (SBP), variceal hemorrhage, model for end-stage liver disease-Na (MELD - Na) ≥ 20, had liver transplantation, malignancy except for squamous cell carcinoma, and other comorbidities such as congestive heart failure (CHF), chronic obstructive pulmonary disease (COPD), and end-stage kidney disease with glomerular filtration rate (GFR) < 30 were excluded. Patients' records from the liver clinic were reviewed and demographics, laboratory, and compensation and decompensation status were collated. Patients were separated into two groups based on age 50-64 years and age ≥ 65. The primary endpoint was death, and the secondary endpoint was disease progression measured by the baseline to 12-month increase in MELD-Na score. The Kaplan-Meier analysis was conducted to compare the survival between the two groups. Cox regression analysis was performed to identify independent risk factors for poor survival. Results: A total of 191 patients diagnosed with cirrhosis met the inclusion and exclusion criteria. There were 80 patients aged 50-64 years and 111 patients aged ≥ 65 years. Significantly shorter survival times were seen among patients aged ≥ 65 years compared to those aged 50-64 years (73.3 ± 4.8 vs. 151.5 ± 22.7; p < .001). Age of diagnosis ≥ 65 years (p < 0.001), male gender (p = .013), body mass index (BMI) < 30 (p = 0.005), and decompensation (p = 0.008) were found to be independent risk factors for poor survival. MELD-Na scores increased significantly in 12 months of follow-up from baseline, but only in patients with decompensated cirrhosis (p = 0.013). Conclusions: Cirrhotic patients aged ≥ 65 years have significantly poor survival compared to younger patients. A prospective study is needed to further investigate the effect of age and obesity on survival and disease progression in older adult patients with cirrhosis.

13.
Neuropharmacology ; 258: 110097, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39094831

RESUMEN

Aging is characterized by a functional decline in several physiological systems. α-Klotho-hypomorphic mice (Kl-/-) exhibit accelerated aging and cognitive decline. We evaluated whether male and female α-Klotho-hypomorphic mice show changes in the expression of synaptic proteins, N-methyl-d-aspartate receptor (NMDAR) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) subunits, postsynaptic density protein 95 (PSD-95), synaptophysin and synapsin, and the activity of Na+, K+-ATPase (NaK) isoforms in the cerebellum and hippocampus. In this study, we demonstrated that in the cerebellum, Kl-/- male mice have reduced expression of GluA1 (AMPA) compared to wild-type (Kl+/+) males and Kl-/- females. Also, Kl-/- male and female mice show reduced ɑ2/ɑ3-NaK and Mg2+-ATPase activities in the cerebellum, respectively, and sex-based differences in NaK and Mg2+-ATPase activities in both the regions. Our findings suggest that α-Klotho could influence the expression of AMPAR and the activity of NaK isoforms in the cerebellum in a sex-dependent manner, and these changes may contribute, in part, to cognitive decline.


Asunto(s)
Cerebelo , Hipocampo , Proteínas Klotho , Receptores AMPA , Caracteres Sexuales , ATPasa Intercambiadora de Sodio-Potasio , Animales , Cerebelo/metabolismo , Masculino , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/genética , Femenino , Hipocampo/metabolismo , Receptores AMPA/metabolismo , Receptores AMPA/genética , Proteínas Klotho/metabolismo , Ratones , Sinaptofisina/metabolismo , Homólogo 4 de la Proteína Discs Large/metabolismo , Homólogo 4 de la Proteína Discs Large/genética , Ratones Noqueados , Sinapsinas/metabolismo , Sinapsinas/genética , Ratones Endogámicos C57BL , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de N-Metil-D-Aspartato/genética
14.
Adv Mater ; : e2405310, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39152941

RESUMEN

Interfacial Na+ behaviors of sodium (Na) anode severely threaten the stability of sodium-metal batteries (SMBs). This review systematically and in-depth discusses the current fundamental understanding of interfacial Na+ behaviors in SMBs including Na+ migration, desolvation, diffusion, nucleation, and deposition. The key influencing factors and optimization strategies of these behaviors are further summarized and discussed. More importantly, the high-energy-density anode-free sodium metal batteries (AFSMBs) are highlighted by addressing key issues in the areas of limited Na sources and irreversible Na loss. Simultaneously, recent advanced characterization techniques for deeper insights into interfacial Na+ deposition behavior and composition information of SEI film are spotlighted to provide guidance for the advancement of SMBs and AFSMBs. Finally, the prominent perspectives are presented to guide and promote the development of SMBs and AFSMBs.

15.
Bioorg Med Chem ; 112: 117872, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39153378

RESUMEN

Riluzole, the first clinically approved treatment for amyotrophic lateral sclerosis (ALS), represents a successful example of a drug endowed with a multimodal mechanism of action. In recent years, different series of riluzole-based compounds have been reported, including several agents acting as Multi-Target-Directed Ligands (MTLDs) endowed with neuroprotective effects. Aiming at identical twin structures inspired by riluzole (2a-c), a synthetic procedure was planned, but the reactivity of the system took a different path, leading to the serendipitous isolation of benzo[b][1,4]thiazepines 3a-c and expanded intermediates N-cyano-benzo[b][1,4]thiazepines 4a-c, which were fully characterized. The newly obtained structures 3a-c, bearing riluzole key elements, were initially tested in an in vitro ischemia/reperfusion injury protocol, simulating the cerebral stroke. Results identified compound 3b as the most effective in reverting the injury caused by an ischemia-like condition, and its activity was comparable, or even higher than that of riluzole, exhibiting a concentration-dependent neuroprotective effect. Moreover, derivative 3b completely reverted the release of Lactate Dehydrogenase (LDH), lowering the values to those of the control slices. Based on its very promising pharmacological properties, compound 3b was then selected to assess its effects on voltage-dependent Na+ and K+ currents. The results indicated that derivative 3b induced a multifaceted inhibitory effect on voltage-gated currents in SH-SY5Y differentiated neurons, suggesting its possible applications in epilepsy and stroke management, other than ALS. Accordingly, brain penetration was also measured for 3b, as it represents an elegant example of a MTDL and opens the way to further ex-vivo and/or in-vivo characterization.

16.
Proc Natl Acad Sci U S A ; 121(33): e2401109121, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39116136

RESUMEN

Na5YSi4O12 (NYSO) is demonstrated as a promising electrolyte with high ionic conductivity and low activation energy for practical use in solid Na-ion batteries. Solid-state NMR was employed to identify the six types of coordination of Na+ ions and migration pathway, which is vital to master working mechanism and enhance performance. The assignment of each sodium site is clearly determined from high-quality 23Na NMR spectra by the aid of Density Functional Theory calculation. Well-resolved 23Na exchangespectroscopy and electrochemical tracer exchange spectra provide the first experimental evidence to show the existence of ionic exchange between sodium at Na5 and Na6 sites, revealing that Na transport route is possibly along three-dimensional chain of open channel-Na4-open channel. Variable-temperature NMR relaxometry is developed to evaluate Na jump rates and self-diffusion coefficient to probe the sodium-ion dynamics in NYSO. Furthermore, NYSO works well as a dual ion conductor in Na and Li metal batteries with Na3V2(PO4)3 and LiFePO4 as cathodes, respectively.

17.
Small Methods ; : e2400642, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39155809

RESUMEN

Na4Fe3(PO4)2P2O7 is regarded as the most promising polyanionic cathode for sodium-ion batteries (SIBs) due to its superior structural stability, cost-effectiveness, and environmental benignity. However, the low operating voltage inevitably weakens its competitiveness in energy density. Previous works have tried to enhance its operating voltage by Mn doping, which draws on the design idea of LiFexMn1-xPO4 cathode for lithium-ion batteries, but with little success. In this context, uncovering the role of Mn substitution in Na4Fe3-xMnx(PO4)2P2O7 (NFMxPP) cathode is urgently needed. This work discloses the effect of Mn contents on the structure, sodium storage property, and reaction mechanism of NFMxPP cathode for the first time. Introducing a moderate amount of Mn (0.6 ≤ x ≤ 1.2) into NFMxPP can weaken the Fe-O bonding interaction, thus leading to the full utilization of Mn3+/Mn2+ redox couple. As the representative, NFM1.2PP cathode exhibited a high operating voltage of ≈3.3 V with a reversible capacity of 109.2 mAh g-1. Note that a Hard carbon||NFM1.2PP full battery manifests considerably high-capacity retention of 92.3% over 1600 cycles. It is believed that an understanding of the role of Mn substitution in this work will promote the practical application of high voltage NFMxPP cathodes for SIBs.

18.
Ter Arkh ; 96(7): 713-717, 2024 Jul 30.
Artículo en Ruso | MEDLINE | ID: mdl-39106516

RESUMEN

The article discusses the causes and course of the last illness of I.S. Turgenev. The writer was consulted by many famous French and Russian doctors who made various diagnoses and used various methods of treatment. The primary disease that caused Turgenev's death is myxosarcoma (one of the sarcoma variants), involving soft tissues and thoracic vertebrae. The article presents data and discusses alternative diagnostic versions about the nature of the disease and the causes of death of the great Russian writer.


Asunto(s)
Personajes , Humanos , Federación de Rusia , Historia del Siglo XIX
19.
Small ; : e2404992, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39109575

RESUMEN

It is generally accepted that the low-temperature environment typically augments electrolyte viscosity and impedes electrochemical kinetics, thereby diminishing battery performance. However, this prevailing notion, while valid in certain contexts, lacks universality, particularly regarding cycling stability. In this context, the Na-MoS2 batteries serve as a model to elucidate the impacts of low temperatures. By significantly suppressing the pulverization and amorphization of MoS2, the low-temperature milieu effectively mitigates the risk of micro-short circuits induced by the mass shuttling to the Na metal anode, thereby averting performance degradation by self-discharge. Upon cycling, the generated NaxMo3S4 intermediates only at low temperatures benefit the structural and electrochemical stabilizations to counteract the intrinsic performance degradation. The attenuation of kinetics at low temperatures facilitates the accumulation of Na2S, akin to a sustained-release agent within the electrode, steadily furnishing the capacity in long cycling. Moreover, the suppression of polysulfide dissolution and shuttling emerges as a pivotal factor contributing to the cycling stability at low-temperature. These findings provide a rewarding avenue toward understanding of the influence of low temperature on battery performance, as well as the design of practical electrodes and batteries for low-temperature applications.

20.
Artículo en Inglés | MEDLINE | ID: mdl-39089444

RESUMEN

There is a consensus that electroneutral Na+/H+ exchangers (NHEs) are important in branchial Na+ uptake in freshwater fish. There is also widespread belief, based on mammalian data, that EIPA [5-(N-ethyl-N-isopropyl)-amiloride]], and HMA [5-(N,N-hexamethylene)-amiloride)] are more potent and specific in blocking Na+ uptake than amiloride. We evaluated this idea by testing the three drugs at 10-7 to 10-4 M, i.e. 0.1 to 100 µM in two model species, rainbow trout (Oncorhynchus mykiss) and goldfish (Carassius auratus), using 22Na+ to measure unidirectional Na+ influx and efflux rates. In both species, the potency order for inhibiting unidirectional Na+ influx was HMA > amiloride > EIPA (IC50 values in the 10-70 µM range), very different from in mammals. At 100 µM, all three drugs inhibited Na+ influx by >90% in both species, except for amiloride in goldfish (65%). However, at 60-100 µM, all three drugs also stimulated unidirectional Na+ efflux rates, indicating non-specific effects. In trout, HMA and EIPA caused significant increases (2.1- to 2.3-fold) in efflux rates, whereas in goldfish, significant efflux elevations were greater (3.1- to 7.2-fold) with all three drugs. We conclude that the inhibitory potency profile established in mammals does not apply to the NHEs in fish gills, that non-specific effects on Na+ efflux rates are a serious concern, and that EIPA and HMA offer no clear benefits in terms of potency or specificity. Considering its much lower cost, we recommend amiloride as the drug of choice for in vivo experiments on freshwater fishes.

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