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1.
Article de Anglais | MEDLINE | ID: mdl-38968215

RÉSUMÉ

The main challenge in the preparation of MOF-based mixed matrix membranes is to construct a good interface morphology to improve the gas separation performance and stability of the membranes. Herein, high-aspect-ratio ZIF-8 nanoplates for H2/CO2 separation membranes were synthesized by direct template conversion. The ZIF-8 nanoplates were prepared with the commercial Matrimid polymer to form MMMs by the flat scraping method. The homogeneous dispersion of high-aspect-ratio nanoplates in the membrane and the good compatibility between the filler and the matrix caused by the thermal annealing operation improve the gas separation performance and mechanical properties of MMMs. The H2/CO2 selectivity of MMMs loaded with 30 wt % ZIF-8 nanoplates increased to 10.3, and the H2 permeability was 330.1 Barrer. This synthesis method can be extended to prepare various ZIF nanoplates with elevated aspect ratios to obtain excellent performance fillers for gas separation of MMMs. In addition, the thermal annealing operation allows more efficient gas separation in polymer membranes and is a feasible way to design excellent and stable MMMs.

2.
Arch Biochem Biophys ; 758: 110080, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38960345

RÉSUMÉ

Glycyrrhizinic acid (GA) is one of the active substances in licorice root. It exhibits antiviral activity against various enveloped viruses, for example, SARS-CoV-2. GA derivatives are promising biologically active compounds from perspective of developing broad-spectrum antiviral agents. Given that GA nicotinate derivatives (Glycyvir) demonstrate activity against various DNA- and RNA-viruses, a search for a possible mechanism of action of these compounds is required. In the present paper, the interaction of Glycyvir with the transmembrane domain of the SARS-CoV-2 E-protein (ETM) in a model lipid membrane was investigated by NMR spectroscopy and molecular dynamics simulation. The lipid-mediated influence on localization of the SARS-CoV-2 E-protein by Glycyvir was observed. The presence of Glycyvir leads to deeper immersion of the ETM in lipid bilayer. Taking into account that E-protein plays a significant role in virus production and takes part in virion assembly and budding, the data on the effect of potential antiviral agents on ETM localization and structure in the lipid environment may provide a basis for further studies of potential coronavirus E-protein inhibitors.

3.
J Colloid Interface Sci ; 674: 925-937, 2024 Jun 29.
Article de Anglais | MEDLINE | ID: mdl-38959738

RÉSUMÉ

Proton exchange membranes with high ionic conductivity and good chemical stability are critical for achieving high power density and long lifespan of direct methanol cells (DMFCs). Herein, a zwitterionic molecule was grafted onto the surface of polyvinylidene fluoride (PVDF) nanofibers to obtain functionalized PVDF porous substrate (SBMA-PDA@PVDF). Then, sulfonated poly(ether ether ketone) (SPEEK) was filled into the pores of SBMA-PDA@PVDF, and further ionic cross-linked via H2SO4 to prepare the composite membrane (SBMA-PDA@PVDF/SPEEK). The basic groups on the zwitterionic interface could not only establish ionic cross-linking with SPEEK to increase chemical stability and reduce swelling, but also serve as the adsorption sites for subsequent H2SO4 cross-linking to significantly enhance proton conductivity. Super-high proton conductivity (165.34 mS cm-1, 80 °C) was achieved for the membrane, which was 2.12 times higher than that of the pure SPEEK. Moreover, the SBMA-PDA@PVDF/SPEEK membrane exhibited remarkably improved oxidative stability of 91.6 % mass retention after soaking in Fenton's agent for 12 h, while pure SPEEK completely decomposed. Satisfactorily, the DMFC assembled with SBMA-PDA@PVDF/SPEEK exhibited a peak power density of 99.01 mW cm-2, which was twice as much as that of commercial Nafion 212 (48.88 mW cm-2). After 235 h durability test, only 11 % voltage loss was observed.

4.
Biophys J ; 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38961623

RÉSUMÉ

Proton circuits within biological membranes, the foundation of natural bioenergetic systems, are significantly influenced by the lipid compositions of different biological membranes. In this study, we investigate the influence of mixed lipid membrane composition on the proton transfer (PT) properties on the surface of the membrane. We track the excited-state PT (ESPT) process from a tethered probe to the membrane with time-scales and length-scales of PT relevant to bioenergetic systems. Two processes can happen during ESPT: the initial PT from the probe to the membrane at short timescales, followed by diffusion of dissociated protons around the probe on the membrane, and the possible geminate recombination with the probe at longer timescales. Here, we use membranes composed of mixtures of phosphatidylcholine (PC) and phosphatidic acid (PA). We show that the changes in the ESPT properties are not monotonous with the concentration of the lipid mixture; at low concentration of PA in PC, we find that the membrane is a poor proton acceptor. Molecular dynamics simulations indicate that the membrane is more structured at this specific lipid mixture with the least defects. Accordingly, we suggest that the structure of the membrane is an important factor in facilitating PT. We further show that the composition of the membrane affects the geminate proton diffusion around the probe, whereas, on a time-scale of tens of nanoseconds, the dissociated proton is mostly lateral restricted to the membrane plane in PA membranes, while in PC, the diffusion is less restricted by the membrane.

5.
Chem Phys Lipids ; 263: 105417, 2024 Jun 29.
Article de Anglais | MEDLINE | ID: mdl-38950675

RÉSUMÉ

Chondroitin sulfates (CSs) are important components of the extracellular matrix and side chains of membrane proteoglycans. These polysaccharides are, therefore, likely to interact with plasma membranes and play a significant role in modulating cellular functions. So far, the details of the processes occurring at the interface between the extracellular matrix and cellular membranes are not fully understood. In this study, we used experimental methods and atomic-scale molecular dynamics (MD) simulations to reveal the molecular picture of the interactions between CS and phosphocholine (PC) membranes, used as a simplified model of cell membranes. MD simulations reveal that the polysaccharide associates to the PC bilayer as a result of electrostatic interactions between the positively charged quaternary ammonium groups of choline and the negatively charged sulfate groups of CS. Compared to an aqueous medium, the adsorbed polysaccharide chains adopt more elongated conformations, which facilitates the electrostatic interactions with the membrane, and have a high degree of freedom to change their conformations and to adhere to and detach from the membrane surface. Penetrating slightly between the polar groups of the bilayer, they form a loosely anchored layer, but do not intrude into the hydrophobic region of the PC bilayer. The CS adsorption spread the PC headgroups apart, which is manifested by an increase in the value of the area pre lipid. The expansion of the lipid polar groups weakens the dispersion interactions between the lipid acyl chains. As a result, the lipid membrane in the membrane-polysaccharide contact areas becomes more fluid. Our outcomes may help to understand in detail the interaction of chondroitin sulfate with zwitterionic membranes at the molecular level, which is of biological interest since many biological processes depend on lipid-CS interactions.

6.
Article de Anglais | MEDLINE | ID: mdl-38958638

RÉSUMÉ

Isoporous membranes produced from diblock copolymers commonly display a poor mechanical property that shows many negative impacts on their separation application. It is theoretically predicted that dense films produced from symmetric triblock copolymers show much stronger mechanical properties than those of homologous diblock copolymers. However, to the best of our knowledge, symmetric triblock copolymers have rarely been fabricated into isoporous membranes before, and a full understanding of separation as well as mechanical properties of membranes prepared from triblock copolymers and homologous diblock copolymers has not been conducted, either. In this work, a cleavable symmetric triblock copolymer with polystyrene as the side block and poly(4-vinylpyridine) (P4VP) as the middle block was synthesized and designed by the RAFT polymerization using the symmetric chain transfer agent, which located at the center of polymer chains and could be removed to produce homologous diblock copolymers with half-length while having the same composition as that found in triblock copolymers. The self-assembly of these two copolymers in thin films and casting solutions was first investigated, observing that they displayed similar self-organized structures under these two conditions. When fabricated into isoporous membranes, they showed similar pore sizes (5-7% difference) and comparable rejection performance (∼10% difference). However, isoporous membranes produced from triblock copolymers showed significantly improved mechanical strength and higher toughness (2-10 times larger) as evidenced by the compacting resistance, strain-stress determination, and nanoindentation testing, suggesting the unique and novel structure-performance relationship in the isoporous membranes produced from symmetric triblock copolymers. The above finding will guide the way to fabricate mechanically robust isoporous membranes without notably changing the separation performance from rarely used symmetric triblock copolymers, which can be synthesized by the controlled polymerization as facilely as that found for diblock copolymers.

7.
Article de Anglais | MEDLINE | ID: mdl-38946314

RÉSUMÉ

INTRODUCTION: To compare neonatal, obstetrical, and maternal outcomes associated with outpatient versus inpatient management of pregnancies with preterm prelabor rupture of membranes (PPROM). MATERIAL AND METHODS: A search of MEDLINE, EMBASE, the Cochrane Database and Central Register from January 1, 1990 to July 31, 2023 identified randomized controlled trials (RCTs) and cohort studies comparing outpatient with inpatient management for pregnant persons diagnosed with PPROM before 37 weeks' gestation. No language restriction was applied. We applied a random effects model for meta-analysis. Trustworthiness was assessed using recently published guidance and Risk of bias using the RoB 2.0 tool for RCTs and ROBINS-I tool for cohort studies. The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach was used to assess the certainty of evidence (COE). Outcomes of interest included perinatal mortality, neonatal morbidities, latency and gestational age at delivery, and maternal morbidities. RCTs and cohort studies were analyzed separately. This study was registered in the International Prospective Register of Systematic Reviewsr: CRD42022295275. RESULTS: From 2825 records, two RCTs and 10 cohort studies involving 1876 patients were included in the review and meta-analysis. Outpatient management protocols varied but generally included brief initial hospitalization, strict eligibility criteria, and surveillance with laboratory and ultrasound investigations. Outpatient management showed lower rates of neonatal respiratory distress syndrome (cohort: RR 0.63 [0.52-0.77, very low COE]), longer latency to delivery (RCT: MD 7.43 days [1.14-13.72 days, moderate COE], cohort: MD 8.78 days [2.29-15.26 days, low COE]), higher gestational age at birth (cohort: MD 7.70 days [2.02-13.38 days, low COE]), lower rates of Apgar scores <7 at 5 min of life (cohort: RR 0.66 [0.50-0.89, very low COE]), and lower rates of histological chorioamnionitis (cohort: RR 0.74 [0.62-0.89, low COE]) without increased risks of adverse neonatal, obstetrical, or maternal outcomes. CONCLUSIONS: Meta-analysis of data from RCTs and cohort studies with very low-to-moderate certainty of evidence indicates that further high-quality research is needed to evaluate the safety and potential benefits of outpatient management for selected PPROM cases, given the moderate-to-high risk of bias in the included studies.

8.
Chimia (Aarau) ; 78(6): 415-422, 2024 Jun 26.
Article de Anglais | MEDLINE | ID: mdl-38946414

RÉSUMÉ

The surge in greenhouse gas emissions, predominantly in the form of carbon dioxide (CO2) spurred by the Industrial Revolution, has surpassed the critical threshold of 400 ppm, fueling global warming, ocean acidification, and climate change. To mitigate the adverse effects of these emissions and limit the global temperature rise to below 2 °C, the ambitious target of achieving net zero emissions by 2050 was established in the Paris Agreement. Current state-of-the-art technologies, such as amine scrubbing, remain problematic owing to their high energy requirements, susceptibility to corrosion, and other operational challenges. Owing to the lack of suitable technologies coupled with escalating energy demand, there is still a significant amount of carbon dioxide being released into the atmosphere. Accordingly, there is an urgent need for the development of alternative technologies that offer high efficiency, low energy consumption, cost-effective installation, and operation. In this review, we delve into the emerging technologies poised to address these challenges, evaluating their maturity levels in comparison to existing commercially available solutions. Furthermore, we provide a brief overview of ongoing efforts aimed at commercializing these innovative technologies.

9.
Cureus ; 16(6): e61754, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38975370

RÉSUMÉ

Introduction Preterm prelabor rupture of membrane (PPROM) contributes to increasing rates of preterm birth, causing greater health risks for newborns. While the mechanisms driving PPROM are not well understood, one hypothesis is that it is due to systemic inflammation, which can be caused by obesity defined as a BMI [Formula: see text]30 kg/m2. The specific aim of the study was to compare neonatal outcomes after PPROM between patients who were obese vs not obese in early pregnancy at a tertiary medical center serving an Appalachian population. Methods An observational, descriptive retrospective review was conducted of the medical records of patients who were diagnosed with PPROM from January 2017 through December 2020. Patients with a single gestation at the time of PPROM without evidence of clinical infection requiring immediate delivery were included. Maternal characteristics, latency management, and birth outcomes were compared between obese ([Formula: see text]30 BMI) and non-obese (<30 BMI) patients. Results Of the 214 women in the study, 129 (60.3%) were obese pre-pregnancy and 85 (39.7%) were not. Most PPROM occurred between 32 and 36 weeks of gestation (145 patients, 67.8%), with 19.2% occurring at 26-31 weeks (41 patients), and 13.2% at <26 weeks of gestation (28 patients). Latency, defined as the days between PPROM and delivery, ranged from 0 to 80 days with a mean of 4.9 + 10.9 days. At least one day of latency was achieved for most patients (144/214; 67.3%). When outcomes were compared between obese and nonobese patients, the obese patients experienced significantly more complications (10.1% vs 2.4%; p=0.031), which were accompanied by greater neonatal morbidity 67 of 129 ((51.9%) vs 30 of 85 (35.3%); p=0.018). Obese women had greater odds that their newborns would experience neonatal morbidity than nonobese women (odds ratio, 1.98; 95% confidence interval, 1.1-3.5). Conclusion This study of Appalachian women found that pre-pregnancy BMI [Formula: see text]30 increased the risk of complications and neonatal morbidity after PPROM. To improve birth outcomes, healthcare workers and policymakers must work together to decrease rates of obesity in Appalachian women at or near childbearing age.

10.
Nano Lett ; 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38976365

RÉSUMÉ

Sealing wet porous membranes is a major challenge when fabricating cell encapsulation devices. Herein, we report the development of an Autoclavable Transparent Thermal Cutter (ATTC) for reliably sealing wet nanofibrous membranes. Notably, the ATTC is autoclavable and transparent, thus enabling in situ visualization of the sealing process in a sterile environment and ensuring an appropriate seal. In addition, the ATTC could generate smooth, arbitrary-shaped sealing ends with excellent mechanical properties when sealing PA6, PVDF, and TPU nanofibrous tubes and PP microporous membranes. Importantly, the ATTC could reliably seal wet nanofibrous tubes, which can shoulder a burst pressure up to 313.2 ± 19.3 kPa without bursting at the sealing ends. Furthermore, the ATTC sealing process is highly compatible with the fabrication of cell encapsulation devices, as verified by viability, proliferation, cell escape, and cell function tests. We believe that the ATTC could be used to reliably seal cell encapsulation devices with minimal side effects.

11.
Am J Obstet Gynecol MFM ; : 101423, 2024 Jul 06.
Article de Anglais | MEDLINE | ID: mdl-38977063

RÉSUMÉ

BACKGROUND: Seven days of antibiotics are recommended in the setting of preterm premature rupture of membranes (PPROM) to promote latency. Azithromycin has generally replaced a seven-day course of erythromycin in current clinical practice. Azithromycin clears from plasma quickly and concentrates in local tissue which is why daily dosing is not always needed and local tissue, rather than plasma, concentrations are used to determine dosing. Based on limited pharmacokinetic studies in pregnancy, 1g one time dose of azithromycin may not maintain local (amniotic fluid) drug concentrations above minimum inhibitory concentrations (MIC50) for common genitourinary pathogens (50-500ng/ml). OBJECTIVE: We aim to compare the pharmacokinetics of one-time vs daily dosing of azithromycin in the setting of preterm pre-labor rupture of membranes (PPROM) STUDY DESIGN: This is a randomized clinical trial of singletons with PPROM randomized to 1gram oral azithromycin once or 500mg oral azithromycin daily x7 days. Primary outcome was amniotic fluid azithromycin concentrations over 8 days. Secondary outcomes included plasma azithromycin trough concentrations. Plasma was collected at time points 1-4hrs and 12-24hrs after first dose, and then every 24hrs through 8 days. Amniotic fluid was collected opportunistically throughout the day noninvasively with Always Flex-foam pads. We aimed to enroll 20 participants to achieve N=5 still pregnant through 8 days in each group. Continuous variables compared with Mann Whitney U test and relationship between azithromycin concentration and time assessed with linear regression. RESULTS: The study was halted after N=6 enrolled due to lagging enrollment, with 3 in each group. The mean gestational age of enrollment was 27.1±1.7weeks in the 1g group and 31.0±1.4 weeks in the 500mg daily group. One participant in each group had latency to delivery >7days. Regarding amniotic fluid azithromycin concentration, there was a difference in change in amniotic fluid azithromycin concentration over time between groups (p<0.001). Amniotic fluid concentration of azithromycin was relatively stable in the 1g once group (B=-0.07 (-0.44 - 0.31), p=0.71), in contrast, amniotic fluid concentration (ng/ml) increased over time (hours) in the 500mg daily group (B=1.3 (0.7 - 1.9), p<0.001). By ≥96hours median amniotic fluid levels of azithromycin were lower in the 1g once dosing group (median 11[7-56]) compared to 500mg daily (median 46 [23-196]), with a median difference -27 (-154 to -1), p=0.03. In plasma, there was higher azithromycin concentration during the first 24hrs with 1g once vs 500mg daily (median difference 637ng/ml (101-1547), p=0.01), however by ≥96hrs plasma azithromycin declined and was virtually undetectable in the 1g once group, while trough plasma levels in the 500mg remained elevated (median difference -207ng/ml (-271 to -155), p=0.03). CONCLUSION: 500mg daily dosing of azithromycin maintains higher amniotic fluid concentrations, and more consistently greater than common MICs, over eight days compared to 1g once in the setting of PPROM.

12.
Methods Enzymol ; 700: 235-273, 2024.
Article de Anglais | MEDLINE | ID: mdl-38971602

RÉSUMÉ

Hierarchic self-assembly is the main mechanism used to create diverse structures using soft materials. This is a case for both synthetic materials and biomolecular systems, as exemplified by the non-covalent organization of lipids into membranes. In nature, lipids often assemble into single bilayers, but other nanostructures are encountered, such as bilayer stacks and tubular and vesicular aggregates. Synthetic block copolymers can be engineered to recapitulate many of the structures, forms, and functions of lipid systems. When block copolymers are amphiphilic, they can be inserted or co-assembled into hybrid membranes that exhibit synergistic structural, permeability, and mechanical properties. One example is the emergence of lateral phase separation akin to the raft formation in biomembranes. When higher-order structures, such as hybrid membranes, are formed, this lateral phase separation can be correlated across membranes in the stack. This chapter outlines a set of important methods, such as X-ray Scattering, Atomic Force Microscopy, and Cryo-Electron Microscopy, that are relevant to characterizing and evaluating lateral and correlated phase separation in hybrid membranes at the nano and mesoscales. Understanding the phase behavior of polymer-lipid hybrid materials could lead to innovative advancements in biomimetic membrane separation systems.


Sujet(s)
Cryomicroscopie électronique , Double couche lipidique , Microscopie à force atomique , Polymères , Cryomicroscopie électronique/méthodes , Polymères/composition chimique , Double couche lipidique/composition chimique , Microscopie à force atomique/méthodes , Diffraction des rayons X/méthodes ,
13.
Methods Enzymol ; 700: 455-483, 2024.
Article de Anglais | MEDLINE | ID: mdl-38971610

RÉSUMÉ

Over the years, it has become more and more obvious that lipid membranes show a very complex behavior. This behavior arises in part from the large number of different kinds of lipids and proteins and how they dynamically interact with each other. In vitro studies using artificial membrane systems have shed light on the heterogeneity based on lipid-lipid interactions in multicomponent bilayer mixtures. Inspired by the raft hypothesis, the coexistence of liquid-disordered (ld) and liquid-ordered (lo) phases has drawn much attention. It was shown that ternary lipid mixtures containing low- and high-melting temperature lipids and cholesterol can phase separate into a lo phase enriched in the high-melting lipids and cholesterol and a ld phase enriched in the low-melting lipids. Depending on the model membrane system under investigation, different domain sizes, shapes, and mobilities have been found. Here, we describe how to generate phase-separated lo/ld phases in model membrane systems termed pore-spanning membranes (PSMs). These PSMs are prepared on porous silicon substrates with pore sizes in the micrometer regime. A proper functionalization of the top surface of the substrates is required to achieve the spreading of giant unilamellar vesicles (GUVs) to obtain PSMs. Starting with lo/ld phase-separated GUVs lead to membrane heterogeneities in the PSMs. Depending on the functionalization strategy of the top surface of the silicon substrate, different membrane heterogeneities are observed in the PSMs employing fluorescence microscopy. A quantitative analysis of the heterogeneity as well as the dynamics of the lipid domains is described.


Sujet(s)
Double couche lipidique , Double couche lipidique/composition chimique , Lipides membranaires/composition chimique , Lipides membranaires/métabolisme , Porosité , Microdomaines membranaires/composition chimique , Microdomaines membranaires/métabolisme , Cholestérol/composition chimique
14.
Article de Anglais | MEDLINE | ID: mdl-38979627

RÉSUMÉ

Cancer immunotherapy is developing as the mainstream strategy for treatment of cancer. However, the interaction between the programmed cell death protein-1 (PD-1) and the programmed death ligand 1 (PD-L1) restricts T cell proliferation, resulting in the immune escape of tumor cells. Recently, immune checkpoint inhibitor therapy has achieved clinical success in tumor treatment through blocking the PD-1/PD-L1 checkpoint pathway. However, the presence of M2 tumor-associated macrophages (TAMs) in the tumor microenvironment (TME) will inhibit antitumor immune responses and facilitate tumor growth, which can weaken the effectiveness of immune checkpoint inhibitor therapy. The repolarization of M2 TAMs into M1 TAMs can induce the immune response to secrete proinflammatory factors and active T cells to attack tumor cells. Herein, hollow iron oxide (Fe3O4) nanoparticles (NPs) were prepared for reprogramming M2 TAMs into M1 TAMs. BMS-202, a small-molecule PD-1/PD-L1 inhibitor that has a lower price, higher stability, lower immunogenicity, and higher tumor penetration ability compared with antibodies, was loaded together with pH-sensitive NaHCO3 inside hollow Fe3O4 NPs, followed by wrapping with macrophage membranes. The formed biomimetic FBN@M could produce gaseous carbon dioxide (CO2) from NaHCO3 in response to the acidic TME, breaking up the macrophage membranes to release BMS-202. A series of in vitro and in vivo assessments revealed that FBN@M could reprogram M2 TAMs into M1 TAMs and block the PD-1/PD-L1 pathway, which eventually induced T cell activation and the secretion of TNF-α and IFN-γ to kill the tumor cells. FBN@M has shown a significant immunotherapeutic efficacy for tumor treatment.

15.
Small ; : e2403915, 2024 Jul 07.
Article de Anglais | MEDLINE | ID: mdl-38973115

RÉSUMÉ

In 2D materials, a key engineering challenge is the mass production of large-area thin films without sacrificing their uniform 2D nature and unique properties. Here, it is demonstrated that a simple fluid phenomenon of water/alcohol solvents can become a sophisticated tool for self-assembly and designing organized structures of 2D nanosheets on a water surface. In situ, surface characterizations show that water/alcohol droplets of 2D nanosheets with cationic surfactants exhibit spontaneous spreading of large uniform monolayers within 10 s. Facile transfer of the monolayers onto solid or flexible substrates results in high-quality mono- and multilayer films with high coverages (>95%) and homogeneous electronic/optical properties. This spontaneous spreading is quite general and can be applied to various 2D nanosheets, including metal oxides, graphene oxide, h-BN, MoS2, and transition metal carbides, enabling on-demand smart manufacture of large-size (>4 inchϕ) 2D nanofilms and free-standing membranes.

16.
Article de Anglais | MEDLINE | ID: mdl-38973223

RÉSUMÉ

INTRODUCTION: Treatment of oligohydramnios in the mid-trimester is challenging, because of the high incidence of adverse perinatal outcomes mainly due to bronchopulmonary dysplasia. Antenatal amnioinfusion has been proposed as a possible treatment for oligohydramnios with intact amnions, but there are few relevant studies. This study aimed to evaluate the effectiveness of transabdominal amnioinfusion in the management of oligohydramnios without fetal lethal malformations in the second and early third trimesters. MATERIAL AND METHODS: It is a historical cohort study. A total of 79 patients diagnosed with oligohydramnios at 18-32 weeks gestation were enrolled. In the amnioinfusion group (n = 39), patients received transabdominal amnioinfusion with the assistance of real-time ultrasound guidance. In the expectant group (n = 41), patients were treated with 3000 mL of intravenous isotonic fluids daily. The perioperative complications and perinatal outcomes were analyzed. RESULTS: Compared with the expectant group, the delivery latency was significantly prolonged, and the rate of cesarean delivery was significantly reduced in the amnioinfusion group (p < 0.05). Although the rate of intrauterine fetal death was significantly reduced, the incidence of spontaneous miscarriage, premature rupture of membranes (PROMs), and threatened preterm labor were significantly higher in the amnioinfusion group than in the expectant group (p < 0.05). There was no significant difference in terms of perinatal mortality (28.9% vs. 41.4%, p > 0.05). Multivariate logistic regression revealed that amnioinfusion (odds ratio [OR] 0.162, 95% confidence interval [CI] 0.04-0.61, p = 0.008) and gestational age at diagnosis (OR 0.185, 95% CI 0.04-0.73, p = 0.016) were independently associated with neonatal adverse outcomes. Further subgrouping showed that amnioinfusion significantly reduced the frequency of bronchopulmonary hypoplasia for patients ≤26 weeks (26.7% vs. 75.0%, p = 0.021). The rates of other neonatal complications were similar in both groups. CONCLUSIONS: Amnioinfusion has no significant effect on improving the perinatal mortality of oligohydramnios in the second and early third trimesters. It may lead to a relatively high rate of PROM and spontaneous abortion. However, amnioinfusion may significantly improve the latency period, the rate of cesarean delivery, and neonatal outcomes of oligohydramnios, especially for women ≤26 weeks with high risk of neonatal bronchopulmonary hypoplasia.

17.
Chemosphere ; : 142730, 2024 Jun 29.
Article de Anglais | MEDLINE | ID: mdl-38950742

RÉSUMÉ

Photocatalytic membranes are a promising technology for water and wastewater treatment. Towards circular economy, extending the lifetime of reverse osmosis (RO) membranes for as long as possible is extremely important, due to the great amount of RO modules discarded every year around the world. Therefore, in the present study, photocatalytic membranes made of recycled post-lifespan RO membrane (polyamide thin-film composite), TiO2 nanoparticles and graphene oxide are used in the treatment tertiary-treated domestic wastewater to remove trace organic compounds (TrOCs). The inclusion of dopamine throughout the surface modification process enhanced the stability of the membranes to be used as long as 10 months of operation. We investigated TrOCs removal by the membrane itself and in combination with UV-C and visible light by LED. The best results were obtained with integrated membrane UV-C system at pH 9, with considerable reductions of diclofenac (92%) and antipyrine (87%). Changes in effluent pH demonstrated an improvement in the attenuation of TrOCs concentration at higher pHs. By modifying membranes with nanocomposites, an increase in membrane hydrophilicity (4 degrees contact angle reduction) was demonstrated. The effect of the lamp position on the light fluence that reaches the membrane was assessed, and greater values were found in the middle of the membrane, providing parameters for process optimization (0.29 ± 0.10 mW cm-2 at the center of the membrane and 0.07 ± 0.03 mW cm-2 at the right and left extremities). Photocatalytic recycled TiO2-GO membranes have shown great performance to remove TrOCs and extend membrane lifespan, as sustainable technology to treat wastewater.

18.
Sci Rep ; 14(1): 15044, 2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38951634

RÉSUMÉ

Acoustic metamaterials are growing in popularity for sound applications including noise control. Despite this, there remain significant challenges associated with the fabrication of these materials for the sub-100 Hz regime, because acoustic metamaterials for such frequencies typically require sub-mm scale features to control sound waves. Advances in additive manufacturing technologies have provided practical methods for rapid fabrication of acoustic metamaterials. However, there is a relatively high sensitivity of their resonant characteristics to sub-mm deviations in geometry, pushing the limits of additive manufacturing. One way of overcoming this is via active control of device resonance. Here, an acoustic metamaterial cell with adjustable resonance is demonstrated for the sub-100 Hz regime. A functionally superparamagnetic membrane-devised to facilitate the fabrication process by eliminating magnetic poling requirements-is engineered using stereolithography, and its mechanical and acoustic properties are experimentally measured using laser Doppler vibrometry and electret microphone testing, with a mathematical model developed to predict the cell response. It is demonstrated that an adjustable magnetic acoustic metamaterial can be fabricated at ultra-subwavelength dimensions ( ≤ λ /77.5), exhibiting adjustable resonance from 88.73 to 86.63 Hz. It is anticipated that this research will drive new innovations in adjustable metamaterials, including wider frequency ranges.

19.
bioRxiv ; 2024 Jun 17.
Article de Anglais | MEDLINE | ID: mdl-38948777

RÉSUMÉ

The protein alpha-synuclein (αSyn) plays a critical role in the pathogenesis of synucleinopathy, which includes Parkinson's disease and multiple system atrophy, and mounting evidence suggests that lipid dyshomeostasis is a critical phenotype in these neurodegenerative conditions. Previously, we identified that αSyn localizes to mitochondria-associated endoplasmic reticulum membranes (MAMs), temporary functional domains containing proteins that regulate lipid metabolism, including the de novo synthesis of phosphatidylserine. In the present study, we have analyzed the lipid composition of postmortem human samples, focusing on the substantia nigra pars compacta of Parkinson's disease and controls, as well as three less affected brain regions of Parkinson's donors. To further assess synucleinopathy-related lipidome alterations, similar analyses were performed on the striatum of multiple system atrophy cases. Our data show region-and disease-specific changes in the levels of lipid species. Specifically, our data revealed alterations in the levels of specific phosphatidylserine species in brain areas most affected in Parkinson's disease. Some of these alterations, albeit to a lesser degree, are also observed multiples system atrophy. Using induced pluripotent stem cell-derived neurons, we show that αSyn contributes to regulating phosphatidylserine metabolism at MAM domains, and that αSyn dosage parallels the perturbation in phosphatidylserine levels. Our results support the notion that αSyn pathophysiology is linked to the dysregulation of lipid homeostasis, which may contribute to the vulnerability of specific brain regions in synucleinopathy. These findings have significant therapeutic implications.

20.
Sci Total Environ ; : 174602, 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38986709

RÉSUMÉ

Traditional mining practices not only cause severe environmental issues, but also face the problem of insufficient production capacity of gold to meet its growing demand. The proposed alternative strategies for gold production, such as the extraction of gold from seawater, still keep a formidable challenge due to their strong dependence on adsorbent materials with high capacity, selectivity, and sensitivity, while also needing to meet the demands of being environmentally friendly and cost-effective. In practice, the direct extraction of gold from seawater is limited by its extremely low yield and high energy expenditure. However, if the combination of gold extraction techniques with seawater desalination can substantially reduce the energy consumption, the extraction of gold from seawater will become economical and feasible. In this paper, we evaluate the feasibility of marine gold extraction using reduced graphene oxide membranes (rGOM) during the seawater desalination process. The rGOM can adsorb almost all Au3+ from the solutions with trace concentrations of Au3+ ranging from 10 ppb to 200 ppb. The adsorption quantity is linearly related to the concentration, indicating that the adsorption capacity of rGOM is much higher than the total amount of Au3+ in the solution. Additionally, the rGOM can selectively adsorb 99 % of Au3+ in the mixed solution while hardly adsorbing other common elements in seawater. More importantly, the rGOM exhibits the long-term stability over 30 days when being immersed in the solution, making it directly compatible with the existing seawater desalination processes. These specific properties allow the rGOM to be an ideal candidate for combining the extraction of gold from seawater with seawater desalination processes. Our findings provide a methodology for enhancing the economic efficiency of the extraction of gold from seawater and hold promise for addressing the problem of gold scarcity.

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