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1.
Angew Chem Int Ed Engl ; : e202410566, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103291

RESUMO

Cell therapies such as CAR-T have demonstrated significant clinical successes, driving the investigation of immune cell surface engineering using natural and synthetic materials to enhance their therapeutic performance. However, many of these materials do not fully replicate the dynamic nature of the extracellular matrix (ECM). This study presents a cell surface engineering strategy that utilizes phase-separated peptide coacervates to decorate the surface of immune cells. We meticulously designed a tripeptide, Fmoc-Lys-Gly-Dopa-OH (KGdelta; Fmoc = fluorenylmethyloxycarbonyl; delta = Dopa, dihydroxyphenylalanine), that forms coacervates in aqueous solution via phase separation. These coacervates, mirroring the phase separation properties of ECM proteins, coat the natural killer (NK) cell surface with the assistance of Fe3+ ions and create an outer layer capable of encapsulating monoclonal antibodies (mAb), such as Trastuzumab. The antibody-embedded coacervate layer equips the NK cells with the ability to recognize cancer cells and eliminate them through enhanced antibody-dependent cellular cytotoxicity (ADCC). This work thus presents a unique strategy of cell surface functionalization and demonstrates its use in displaying cancer-targeting mAb for cancer therapies, highlighting its potential application in the field of cancer therapy.

2.
Int J Biol Macromol ; 277(Pt 3): 134433, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39098686

RESUMO

Phosphorus-containing flame retardants are prone to result in the buildup of biotoxins, while halogen flame retardants easily lead to hazardous gases. Therefore, it is crucial to develop a multifunctional flame-retardant cotton fabric without phosphorus and halogen. Herein, single-ended hydroxy-terminated polydimethylsiloxane (PDMS-ID) was synthesized through single-ended hydrosilicone oil and 1,4-butanediol, followed by the preparation of a waterborne polyurethane (RWPU) containing side chain polydimethylsiloxane through the reaction of PDMS-ID with isocyanate prepolymer. Characterization data shows that its particle size distribution is relatively dispersed while maintaining good emulsification performance. Based on this, a halogen-free and phosphorus-free multifunctional flame retardant cotton fabric (COF-BBN@RWPU) was successfully prepared through treatment with boric acid/borax/3-aminopropyltriethoxysilane solution and subsequent RWPU encapsulation. In vertical flammability test (VFT), COF-BBN@RWPU has a char length of 57 mm and a limiting oxygen index (LOI) of 42.3 % with a 11 % weight gain while pure cotton was burned through with a LOI of 18.0 %. In addition, the total heat release and total smoke release of COF-BBN@RWPU decreased by 80.0 % and 47.2 %, compared with pure cotton. Additionally, COF-BBN@RWPU can achieve a maximum contact angle of 140.1° with an oil-water separation rate of 98.4 %. This study presents an eco-friendly approach to achieving the multifunctionality of cellulose fabrics.


Assuntos
Fibra de Algodão , Dimetilpolisiloxanos , Retardadores de Chama , Poliuretanos , Poliuretanos/química , Retardadores de Chama/análise , Dimetilpolisiloxanos/química , Fibra de Algodão/análise , Têxteis , Química Verde/métodos
3.
Int J Biol Macromol ; 270(Pt 1): 132330, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750840

RESUMO

Developing flame retardant cotton fabrics (CF) is crucial for minimizing the harm caused by fires to people. To improve the flame retardancy of CF, this paper has synthesized a novel flame retardant called diboraspiro tetra phosphonate ammonium salt (N-PDBDN). The structure of N-PDBDN has been analyzed using FT-IR and NMR. Treating CF with N-PDBDN can increase the limiting oxygen index (LOI) to 36.2 % with a weight gain of 10.1 %. Moreover, even after undergoing 50 laundering cycles (LCs), the LOI remains at 27.1 %, indicating good flame retardancy and durability. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) show the presence of P and N elements on N-PDBDN treated CF, suggesting successful bonding between N-PDBDN and cellulose. Thermogravimetric analysis (TGA) results demonstrate that the addition of N-PDBDN significantly enhances the thermal stability and carbon formation ability of CF. Furthermore, cone calorimetry tests reveal reduced heat release rates (HRR), prolonged time to ignition (TTI), and 38 % lower total heat release (THR) in CF treated with N-PDBDN compared with pure cotton. Finally, a potential flame retardant mechanism involving N-PDBDN is proposed. These findings indicate that incorporating an ammonium phosphate group into CF can effectively improve the flame retardancy and durability.


Assuntos
Fibra de Algodão , Retardadores de Chama , Têxteis , Nitrogênio/química , Fósforo/química , Espectroscopia de Infravermelho com Transformada de Fourier , Organofosfonatos/química , Termogravimetria
4.
Int J Womens Health ; 16: 843-851, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774152

RESUMO

Background: Hemophagocytic lymphohistiocytosis (HLH) is a severe hyperinflammatory syndrome characterized by excessive activation of NK cells and cytotoxic T lymphocytes, subsequently leading to macrophage activation and increased cytokine production. Misdiagnosis due to nonspecific clinical presentations and inadequate understanding of the disease can significantly jeopardize the safety of both the mother and the infant. We report a case of pregnancy combined with HLH and conduct a literature review to provide insights into the diagnosis and treatment of pregnancy-related HLH. Case Presentation: We discussed a case of a pregnant woman with persistent postpartum fever, serum ferritin, and elevated liver function, who failed to respond to repeated anti-infective therapy and was diagnosed with HLH after multidisciplinary diagnostic treatment. We gave dexamethasone treatment, and the patient's temperature and blood cells quickly returned to normal. Finally, exome sequencing revealed heterozygous variation in UNC13D gene, so we considered this case as pregnancy combined with primary HLH (pHLH). Conclusion: We report the case of HLH diagnosed during pregnancy and show that early diagnosis and timely intervention can prevent rapid disease progression, reduce maternal mortality rates, and improve survival rates. Additionally, molecular genetic testing can confirm pathogenic gene mutations, providing essential genetic counseling for patients with pHLH who plan to conceive a healthy child.

5.
Ying Yong Sheng Tai Xue Bao ; 35(3): 827-836, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38646771

RESUMO

The proportion and area of ratoon rice planting in China have been substantially increased, due to continuous improvement of rice breeding methods and consecutive innovation of cultivation technology, which has developed into one of rice planting modes with significant production efficiency. Combining the experience in research and practice, from the perspective of crop physiology and ecology, we reviewed the current situation and prospects of high-yielding formation and physiological mechanisms of ratoon rice. We focused on four key aspects: screening and breeding of ratoon rice cultivars and the classification; suitable stubble height for mechanically harvested ratoon rice, as well as water and fertilizer management; dry matter production and allocation in ratoon rice and the relationship with yield formation; regenerative activity and vigor of ratoon rice roots and their relationship with rhizosphere micro-ecological characteristics. As for the extending of mechanized low-cut stubbles ratoon rice technique, we should properly regulate the rhizosphere system, coordinate rhizosphere nutrient supply, germination of axillary buds, and tillering regeneration, to achieve the target of "four-high-one-low", that is high regeneration coefficient, high number of regeneration panicle, high harvest index, high yield, high quality, low-carbon and safe, aiming to improve the sustainability of ratoon rice industry.


Assuntos
Oryza , Oryza/crescimento & desenvolvimento , China , Produção Agrícola/métodos , Rizosfera , Melhoramento Vegetal , Agricultura/métodos , Fertilizantes , Raízes de Plantas/crescimento & desenvolvimento
6.
Materials (Basel) ; 17(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612149

RESUMO

Perovskite-style materials are cathode systems known for their stability in solid oxide fuel cells (SOFCs). Pr0.5Sr0.5FeO3-δ (PSF) exhibits excellent electrode performance in perovskite cathode systems at high temperatures. Via VB subgroup metals (V, Nb, and Ta) modifying the B-site, the oxidation and spin states of iron elements can be adjusted, thereby ultimately adjusting the cathode's physicochemical properties. Theoretical predictions indicate that PSF has poor stability, but the relative arrangement of the three elements on the B-site can significantly improve this material's properties. The modification of Nb has a large effect on the stability of PSF cathode materials, reaching a level of -2.746 eV. The surface structure of PSF becomes slightly more stable with an increase in the percentage of oxygen vacancy structures, but the structural instability persists. Furthermore, the differential charge density distribution and adsorption state density of the three modified cathode materials validate our adsorption energy prediction results. The initial and final states of the VB subgroup metal-doped PSF indicate that PSFN is more likely to complete the cathode surface adsorption reaction. Interestingly, XRD and EDX characterization are performed on the synthesized pure and Nb-doped PSF material, which show the orthorhombic crystal system of the composite theoretical model structure and subsequent experimental components. Although PSF exhibits strong catalytic activity, it is highly prone to decomposition and instability at high temperatures. Furthermore, PSFN, with the introduction of Nb, shows greater stability and can maintain its activity for the ORR. EIS testing clearly indicates that Nb most significantly improves the cathode. The consistency between the theoretical predictions and experimental validations indicates that Nb-doped PSF is a stable and highly active cathode electrode material with excellent catalytic activity.

7.
J Control Release ; 370: 302-309, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38663752

RESUMO

Displaying antibodies on carrier surfaces facilitates precise targeting and delivery of drugs to diseased cells. Here, we report the synthesis of antibody-lipid conjugates (ALCs) through site-selective acetylation of Lys 248 in human Immunoglobulin G (IgG) and the development of antibody-functionalized red blood cells (immunoRBC) for targeted drug delivery. ImmunoRBC with the HER2-selective antibody trastuzumab displayed on the surface (called Tras-RBC) was constructed following a three-step procedure. First, a peptide-guided, proximity-induced reaction transferred an azidoacetyl group to the ε-amino group of Lys 248 in the Fc domain. Second, the azide-modified IgG was subsequently conjugated with dibenzocyclooctyne (DBCO)-functionalized lipids via strain-promoted azide-alkyne cycloaddition (SPAAC) to result in ALCs. Third, the lipid portion of ALCs was then inserted into the cell membranes, and IgGs were displayed on red blood cells (RBCs) to construct immunoRBCs. We then loaded Tras-RBC with a photosensitizer (PS), Zinc phthalocyanine (ZnPc), to selectively target HER2-overexpressing cells, release ZnPc into cancer cells following photolysis, and induce photodynamic cytotoxicity in the cancer cells. This work showcases assembling immunoRBCs following site-selective lipid conjugation on therapeutic antibodies and the targeted introduction of PS into cancer cells. This method could apply to the surface functionalization of other membrane-bound vesicles or lipid nanoparticles for antibody-directed drug delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Eritrócitos , Indóis , Isoindóis , Lipídeos , Trastuzumab , Humanos , Eritrócitos/efeitos dos fármacos , Trastuzumab/química , Trastuzumab/administração & dosagem , Lipídeos/química , Indóis/química , Indóis/administração & dosagem , Compostos de Zinco , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/química , Compostos Organometálicos/química , Compostos Organometálicos/administração & dosagem , Receptor ErbB-2/imunologia , Imunoconjugados/química , Imunoconjugados/administração & dosagem , Imunoglobulina G/química , Linhagem Celular Tumoral , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/química , Azidas/química
8.
Plants (Basel) ; 13(3)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38337971

RESUMO

Reducing greenhouse gas emissions while improving productivity is the core of sustainable agriculture development. In recent years, rice ratooning has developed rapidly in China and other Asian countries, becoming an effective measure to increase rice production and reduce greenhouse gas emissions in these regions. However, the lower yield of ratooning rice caused by the application of a single nitrogen fertilizer in the ratooning season has become one of the main reasons limiting the further development of rice ratooning. The combined application of nitrogen and phosphorus plays a crucial role in increasing crop yield and reducing greenhouse gas emissions. The effects of combined nitrogen and phosphorus application on ratooning rice remain unclear. Therefore, this paper aimed to investigate the effect of combined nitrogen and phosphorus application on ratooning rice. Two hybrid rice varieties, 'Luyou 1831' and 'Yongyou 1540', were used as experimental materials. A control treatment of nitrogen-only fertilization (187.50 kg·ha-1 N) was set, and six treatments were established by reducing nitrogen fertilizer by 10% (N1) and 20% (N2), and applying three levels of phosphorus fertilizer: N1P1 (168.75 kg·ha-1 N; 13.50 kg·ha-1 P), N1P2 (168.75 kg·ha-1 N; 27.00 kg·ha-1 P), N1P3 (168.75 kg·ha-1 N; 40.50 kg·ha-1 P), N2P1 (150.00 kg·ha-1 N; 13.50 kg·ha-1 P), N2P2 (150.00 kg·ha-1 N; 27.00 kg·ha-1 P), and N2P3 (150.00 kg·ha-1 N; 40.50 kg·ha-1 P). The effects of reduced nitrogen and increased phosphorus treatments in ratooning rice on the yield, the greenhouse gas emissions, and the community structure of rhizosphere soil microbes were examined. The results showed that the yield of ratooning rice in different treatments followed the sequence N1P2 > N1P1 > N1P3 > N2P3 > N2P2 > N2P1 > N. Specifically, under the N1P2 treatment, the average two-year yields of 'Luyou 1831' and 'Yongyou 1540' reached 8520.55 kg·ha-1 and 9184.90 kg·ha-1, respectively, representing increases of 74.30% and 25.79% compared to the N treatment. Different nitrogen and phosphorus application combinations also reduced methane emissions during the ratooning season. Appropriately combined nitrogen and phosphorus application reduced the relative contribution of stochastic processes in microbial community assembly, broadened the niche breadth of microbial communities, enhanced the abundance of functional genes related to methane-oxidizing bacteria and soil ammonia-oxidizing bacteria in the rhizosphere, and decreased the abundance of functional genes related to methanogenic and denitrifying bacteria, thereby reducing greenhouse gas emissions in the ratooning season. The carbon footprint of ratooning rice for 'Luyou 1831' and 'Yongyou 1540' decreased by 25.82% and 38.99%, respectively, under the N1P2 treatment compared to the N treatment. This study offered a new fertilization pattern for the green sustainable development of rice ratooning.

9.
J Colloid Interface Sci ; 661: 228-236, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38301461

RESUMO

HYPOTHESIS: A critical challenge in the enzymatic conversion of acylglycerols is the limited exposure of the enzyme dissolved in the aqueous solution to the hydrophobic substrate in the oil phase. Positioning the enzyme in a microenvironment with balanced hydrophobicity and hydrophilicity in Pickering emulsion will facilitate the acylglycerol-catalyzing reactions at the interface between the oil and liquid phases. EXPERIMENTS: In this work, to overcome the challenge of biphasic catalysis, we report a method to immobilize enzymes in polyethylene glycol (PEG)-based hydrogel microparticles (HMPs) at the interface between the oil and water phases in Pickering emulsion to promote the enzymatic conversion of acylglycerols. FINDINGS: 3 wt% of HMPs can stabilize the oil-in-water Pickering emulsion for at least 14 days and increase the viscosity of emulsions. Lipase-HMP conjugates showed significantly higher hydrolytic activity in Pickering emulsion; HMP-immobilized lipase SMG1 showed an activity about three times that of free lipase SMG1. Co-immobilization of a lipase and a fatty acid photodecarboxylase from Chlorella variabilis (CvFAP) in Pickering emulsion enables light-driven cascade conversion of triacylglycerols to hydrocarbons, transforming waste oil to renewable biofuels in a green and sustainable approach. HMPs stabilize the Pickering emulsion and promote interfacial biocatalysis in converting acylglycerols to renewable biofuels.


Assuntos
Chlorella , Glicerídeos , Emulsões/química , Hidrogéis , Biocombustíveis , Lipase/química
10.
BMC Plant Biol ; 24(1): 62, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38262916

RESUMO

Nectar guide trichomes play crucial ecological roles in bee-pollinated flowers, as they serve as footholds and guides for foraging bees to access the floral rewards. However, the genetic basis of natural variation in nectar guide trichomes among species remains poorly understood. In this study, we performed genetic analysis of nectar guide trichome variation between two closely related monkeyflower (Mimulus) species, the bumblebee-pollinated Mimulus lewisii and self-pollinated M. parishii. We demonstrate that a MIXTA-like R2R3-MYB gene, GUIDELESS, is a major contributor to the nectar guide trichome length variation between the two species. The short-haired M. parishii carries a recessive allele due to non-synonymous substitutions in a highly conserved motif among MIXTA-like MYB proteins. Furthermore, our results suggest that besides GUIDELESS, additional loci encoding repressors of trichome elongation also contribute to the transition from bumblebee-pollination to selfing. Taken together, these results suggest that during a pollination syndrome switch, changes in seemingly complex traits such as nectar guide trichomes could have a relatively simple genetic basis, involving just a few genes of large effects.


Assuntos
Mimulus , Néctar de Plantas , Abelhas , Animais , Tricomas , Polinização , Flores
11.
Int J Biol Macromol ; 260(Pt 1): 129497, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38232884

RESUMO

A new synergistic flame retardant named Bisiminopropyl trimethoxysilane-1,3,5-triazine-O-bicyclic pentaerythritol phosphate (BTPODE) was synthesized, which is a type of Si/P/N flame retardant. This was accomplished by grafting aminopropyl trimethoxysilane and bicyclic pentaerythritol phosphate onto a triazine ring structure, serving as an intermediate. The structure of BTPODE was determined using nuclear magnetic resonance (1H NMR, 13C NMR, and 31P NMR) and Fourier transform infrared spectroscopy (FT-IR). SEM was used to detect the surface morphology of cotton fabrics, which suggested that BTPODE had been resoundingly stick to cotton fabrics. The flame retardant properties of cotton fabrics were evaluated by measuring the limiting oxygen index (LOI) and conducting vertical flammability experiments. Cotton fabrics with a weight gain of 20.73 % achieved an LOI value of 32.5 %. Thermogravimetric (TG) experiments demonstrated the samples' good thermostability. Furthermore, under nitrogen conditions, the char residue of cotton fabric with a weight gain of 20.73 % was 36.85 %. The cone calorimetry test (CONE) showed a significant reduction in the TSP value, indicating a certain level of smoke suppression performance. Finally, based on the obtained experimental results, the fire-retardant mechanism principle of the flame retardant was deduced.


Assuntos
Retardadores de Chama , Propilenoglicóis , Silanos , Humanos , Triazinas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Fosfatos , Aumento de Peso
12.
Chem Biodivers ; 21(2): e202301556, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38095134

RESUMO

Curcumin, derived from the popular spice turmeric, is a pharmacologically active polyphenol. Curcumin's therapeutic activity has been extensively studied in recent decades, with reports implicating curcumin in many biological activities, particularly, its significant anticancer activity. However, its potential as an oral administration product is hampered by poor bioavailability, which is associated with a variety of factors, including low water solubility, poor intestinal permeability, instability, and degradation at alkaline pH. To improve its bioavailability, modifying ß-diketone curcumin with heterocycles, such as pyrazole, isoxazole and triazole is a powerful strategy. Derivatives are synthesized while maintaining the basic skeleton of curcumin. The ß-diketone cyclized curcumin derivatives are regulators of multiple molecular targets, which play vital roles in a variety of cellular pathways. In some literatures, structurally modified curcumin derivatives have been compared with curcumin, and the former has enhanced biological activity, improved water solubility and stability. Therefore, the scope of this review is to report the most recently synthesized heterocyclic derivatives and to classify them according to their chemical structures. Several of the most important and effective compounds are reviewed by introducing different active groups into the ß-diketone position to achieve better therapeutic efficacy and bioavailability.


Assuntos
Curcumina , Curcumina/farmacologia , Curcumina/química , Disponibilidade Biológica , Água
13.
Adv Sci (Weinh) ; 11(5): e2305012, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38044303

RESUMO

Targeted immunotherapies capitalize on the exceptional binding capabilities of antibodies to stimulate a host response that effectuates long-lived tumor destruction. One example is the conjugation of immunoglobulins (IgGs) to immune effector cells, which equips the cells with the ability to recognize and accurately kill malignant cells through a process called antibody-dependent cellular cytotoxicity (ADCC). In this study, a chemoenzymatic reaction is developed that specifically functionalizes a single tyrosine (Tyr, Y) residue, Y296, in the Fc domain of therapeutic IgGs. A one-pot reaction that combines the tyrosinase-catalyzed oxidation of tyrosine to o-quinone with a subsequent [3+2] photoaddition with vinyl ether is employed. This reaction installs fluorescent molecules or bioorthogonal groups at Y296 of IgGs or the C-terminal Y-tag of an engineered nanobody. The Tyr-specific reaction is utilized in constructing monofunctionalized antibody-drug conjugates (ADCs) and antibody/nanobody-conjugated effector cells, such as natural killer cells or macrophages. These results demonstrate the potential of site-selective antibody reactions for enhancing targeted cancer immunotherapy.


Assuntos
Anticorpos , Tirosina , Imunoterapia/métodos , Citotoxicidade Celular Dependente de Anticorpos , Células Matadoras Naturais
14.
Front Cardiovasc Med ; 10: 1171713, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38045914

RESUMO

Atrial fibrillation (AF) is the most commonly sustained arrhythmia after pulmonary resection, which has been shown to predict higher hospital morbidity and mortality. The lack of strong evidence-based medical evidence makes doctors have very few options for medications to prevent new-onset AF following thoracic surgery. Magnesium can prevent perioperative AF in patients undergoing cardiac surgery. However, this has not yet been fully studied in patients undergoing non-cardiac thoracic surgery, which is the aim of this study. This is a single-center, prospective, double-blind, randomized controlled trial. In total, 838 eligible patients were randomly assigned to one of two study groups, namely, the control group or the magnesium group. The patients in the magnesium group preoperatively received 80 mg magnesium sulfate/kg ideal weight in 100 ml normal saline 30 min. The control group received the same volumes of normal saline simultaneously. The primary outcome is the incidence of new-onset AF intra-operative and on the first, second, and third postoperative days. The secondary outcomes are bradycardia, hypertension, hypotension, and flushing. The occurrence of stroke or any other type of arrhythmia is also recorded. Postoperative respiratory suppression and gastrointestinal discomfort, intensive care unit stays and total duration of hospital stays, in-hospital mortality, and 3-month all-cause mortality are also recorded as important outcomes. This study aims to prospectively evaluate the prophylactic effects of magnesium sulfate against AF compared with a placebo control group during and following anatomic pulmonary resection. The results may provide reliable evidence for the prophylactic value of magnesium against AF in patients with lung cancer. The trial was approved by the Clinical Research Ethics Committee of Shanghai Pulmonary Hospital and has been registered at Chinese Clinical Trial Registry: www.chictr.org.cn, identifier: ChiCTR2300068046.

15.
J Pain Res ; 16: 4209-4216, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38090025

RESUMO

Purpose: We examined whether the addition of sufentanil to local anesthetics improves the quality of continuous femoral nerve block in patients undergoing total knee arthroplasty (TKA). Patients and Methods: With institutional ethical approval and having obtained written informed consent from each, 35 patients scheduled for elective bilateral TKA with ASA I or II physical status were studied. Bilateral femoral perineural catheters were preoperatively inserted. Both-sided catheters were randomly assigned to receive perineural ropivacaine of 0.2% plus 0.5µg/mL sufentanil deemed as RS group or 0.2% ropivacaine alone deemed as R group at the end of surgery. Visual analogue pain scores (VAS) during activity and at rest of each lower limb were recorded at 6,12,18,24,30,36,42 and 48h after surgery. During the first 48 postoperative hours, the number and reason of patients sleep interruption at night, the number of painful compressions, patient satisfaction and morphine requirements were recorded for each lower limb of patients. Results: Pain scores of RS group on movement were significantly lower than R group, but no difference was noted at rest. When compared to R group, RS group had a lower incidence of sleep interruption at night, fewer painful compressions, higher satisfaction scores and less morphine requirement. Conclusion: The addition of sufentanil to ropivacaine improved analgesia quality of continuous femoral nerve block after arthroplasty.

16.
bioRxiv ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38106000

RESUMO

Telomeres are nucleoprotein complexes with a crucial role of protecting chromosome ends. It consists of simple repeat sequences and dedicated telomere-binding proteins. Because of its vital functions, components of the telomere, for example its sequence, should be under strong evolutionary constraint. But across all plants, telomere sequences display a range of variation and the evolutionary mechanism driving this diversification is largely unknown. Here, we discovered in Monkeyflower (Mimulus) the telomere sequence is even variable between species. We investigated the basis of Mimulus telomere sequence evolution by studying the long noncoding telomerase RNA (TR), which is a core component of the telomere maintenance complex and determines the telomere sequence. We conducted total RNA-based de novo transcriptomics from 16 Mimulus species and analyzed reference genomes from 6 species, and discovered Mimulus species have evolved at least three different telomere sequences: (AAACCCT)n, (AAACCCG)n, and (AAACCG)n. Unexpectedly, we discovered several species with TR duplications and the paralogs had functional consequences that could influence telomere evolution. For instance, M. lewisii had two sequence-divergent TR paralogs and synthesized a telomere with sequence heterogeneity, consisting of AAACCG and AAACCCG repeats. Evolutionary analysis of the M. lewisii TR paralogs indicated it had arisen from a transposition-mediate duplication process. Further analysis of the TR from multiple Mimulus species showed the gene had frequently transposed and inserted into new chromosomal positions during Mimulus evolution. From our results, we propose the TR transposition, duplication, and divergence model to explain the evolutionary sequence turnovers in Mimulus and potentially all plant telomeres.

17.
Bioorg Med Chem ; 95: 117486, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37847948

RESUMO

Chemotherapy is the mainstay in the treatment of breast cancer. However, many drugs that are commonly used in clinical practice have a high incidence of side effects and multidrug resistance (MDR), which is mainly caused by overexpression of drug transporters and related enzymes in breast cancer cells. In recent years, researchers have been working hard to find newer and safer drugs to overcome MDR in breast cancer. In this review, we provide the molecule mechanism of MDR in breast cancer, categorize potential lead compounds that inhibit single or multiple drug transporter proteins, as well as related enzymes. Additionally, we have summarized the structure-activity relationship (SAR) based on potential breast cancer MDR modulators with lower side effects. The development of novel approaches to suppress MDR is also addressed. These lead compounds hold great promise for exploring effective chemotherapy agents to overcome MDR, providing opportunities for curing breast cancer in the future.


Assuntos
Antineoplásicos , Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Resistência a Múltiplos Medicamentos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
18.
RSC Adv ; 13(41): 28382-28388, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37766935

RESUMO

The anodic catalytic capability of PrFeO3-δ is restricted by the Fe-site element type in the perovskite material structure due to its low electrical conductivity of electrons. Here, we present a strategy for tuning the Fe-site element type via Sr and VB subgroup metals (V, Nb, Ta) co-doping to enhance the anodic catalytic performance of PrFeO3-δ anode materials. Our calculations show that Sr and Nb co-doping has suitable hydrogen adsorption energy for PrFeO3-δ anode materials, and its adsorption energy is adjusted to -0.717 eV, which is more suitable to absorb the hydrogen molecule than other high-profile perovskite anode materials. Meanwhile, after the doped surface is adsorbed by hydrogen molecules, the bond length lengthens until it breaks, and one of the broken hydrogen atoms moves directly above the surface oxygen atom, which is beneficial for accelerating the anodic catalytic reaction. Thus, the Pr0.5Sr0.5Fe0.875Nb0.125O3-δ material is a promising perovskite anode catalyst. Interestingly, the stability of PrFeO3-δ is significantly affected by the oxygen vacancy content; the structural stability of the undoped system can be maintained via Sr and Nb co-doping to avoid decomposition, which provides new thinking to maintain the high stability of perovskite ferrite materials. Furthermore, we find that relative to the PrFeO3-δ, the Pr0.5Sr0.5Fe0.875Nb0.125O3-δ surface of hydrogen adsorption has obvious charge transfer and upward shift of the d-band center. Our anodic catalytic theoretical work shows that Sr and Nb co-doping can effectively enhance the catalytic performance of the PrFeO3-δ ferrite materials.

19.
Sensors (Basel) ; 23(17)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37688111

RESUMO

Enhancing gasoline detergency is pivotal for enhancing fuel efficiency and mitigating exhaust emissions in gasoline vehicles. This study investigated gasoline vehicle emission characteristics with different gasoline detergency, explored synergistic emission reduction potentials, and developed versatile emission prediction models. The results indicate that improved fuel detergency leads to a reduction of 5.1% in fuel consumption, along with decreases of 3.2% in total CO2, 55.4% in CO, and 15.4% in HC emissions. However, during low-speed driving, CO2 and CO emissions reductions are limited, and HC emissions worsen. A synergistic emission reduction was observed, particularly with CO exhibiting a pronounced reduction compared to HC. The developed deep-learning-based vehicle emission model for different gasoline detergency (DPVEM-DGD) enables accurate emission predictions under various fuel detergency conditions. The Pearson correlation coefficients (Pearson's r) between predicted and measured values of CO2, CO, and HC emissions before and after adding detergency agents are 0.913 and 0.934, 0.895 and 0.915, and 0.931 and 0.969, respectively. The predictive performance improves due to reduced peak emissions resulting from improved fuel detergency. Elevated gasoline detergency not only reduces exhaust emissions but also facilitates more refined emission management to a certain extent.

20.
Nat Nanotechnol ; 18(12): 1401-1408, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37653051

RESUMO

Patterning antidots, which are regions of potential hills that repel electrons, into well-defined antidot lattices creates fascinating artificial periodic structures, leading to anomalous transport properties and exotic quantum phenomena in two-dimensional systems. Although nanolithography has brought conventional antidots from the semiclassical regime to the quantum regime, achieving precise control over the size of each antidot and its spatial period at the atomic scale has remained challenging. However, attaining such control opens the door to a new paradigm, enabling the creation of quantum antidots with discrete quantum hole states, which, in turn, offer a fertile platform to explore novel quantum phenomena and hot electron dynamics in previously inaccessible regimes. Here we report an atomically precise bottom-up fabrication of a series of atomic-scale quantum antidots through a thermal-induced assembly of a chalcogenide single vacancy in PtTe2. Such quantum antidots consist of highly ordered single-vacancy lattices, spaced by a single Te atom, reaching the ultimate downscaling limit of antidot lattices. Increasing the number of single vacancies in quantum antidots strengthens the cumulative repulsive potential and consequently enhances the collective interference of multiple-pocket scattered quasiparticles inside quantum antidots, creating multilevel quantum hole states with a tunable gap from the telecom to far-infrared regime. Moreover, precisely engineered quantum hole states of quantum antidots are geometry protected and thus survive on oxygen substitutional doping. Therefore, single-vacancy-assembled quantum antidots exhibit unprecedented robustness and property tunability, positioning them as highly promising candidates for advancing quantum information and photocatalysis technologies.

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