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1.
Annu Rev Cell Dev Biol ; 40(1): 119-142, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39038471

RESUMO

Developmental biology has greatly profited from genetic and reverse genetic approaches to indirectly studying protein function. More recently, nanobodies and other protein binders derived from different synthetic scaffolds have been used to directly dissect protein function. Protein binders have been fused to functional domains, such as to lead to protein degradation, relocalization, visualization, or posttranslational modification of the target protein upon binding. The use of such functionalized protein binders has allowed the study of the proteome during development in an unprecedented manner. In the coming years, the advent of the computational design of protein binders, together with further advances in scaffold engineering and synthetic biology, will fuel the development of novel protein binder-based technologies. Studying the proteome with increased precision will contribute to a better understanding of the immense molecular complexities hidden in each step along the way to generate form and function during development.


Assuntos
Biologia do Desenvolvimento , Animais , Humanos , Ligação Proteica , Proteínas/metabolismo , Proteínas/genética , Proteínas/química , Proteoma/metabolismo , Proteoma/genética , Anticorpos de Domínio Único/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(1): e2216611120, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36574674

RESUMO

Small molecules that bind in the minor groove of DNA are in clinical use as antibiotics and antitumor drugs. Two members of this class of molecules, netropsin and chromomycin, are shown here to displace DNA from the nucleosome and promote transfer of the histone octamer to an acceptor protein. The effects of these groove-binding molecules are exploited to address an outstanding problem in the mechanism of the RSC chromatin remodeling complex. RSC and other remodeling complexes are DNA translocases, acting near the center of the nucleosomal DNA, but translocation is apparently impossible because DNA cannot slide across the histone surface in the nucleosome. Netropsin and chromomycin promote the release of DNA from the histone surface, enhance the formation of a RSC-nucleosome complex, and synergize with RSC in chromatin remodeling. These findings are in keeping with an involvement of bulge translocation in chromatin remodeling.


Assuntos
Nucleossomos , Proteínas de Saccharomyces cerevisiae , Histonas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Montagem e Desmontagem da Cromatina , Relevância Clínica , Netropsina/metabolismo , DNA/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Cromatina
3.
Mol Ther ; 32(6): 1687-1700, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38582966

RESUMO

Deep-learning-based methods for protein structure prediction have achieved unprecedented accuracy, yet their utility in the engineering of protein-based binders remains constrained due to a gap between the ability to predict the structures of candidate proteins and the ability toprioritize proteins by their potential to bind to a target. To bridge this gap, we introduce Automated Pairwise Peptide-Receptor Analysis for Screening Engineered proteins (APPRAISE), a method for predicting the target-binding propensity of engineered proteins. After generating structural models of engineered proteins competing for binding to a target using an established structure prediction tool such as AlphaFold-Multimer or ESMFold, APPRAISE performs a rapid (under 1 CPU second per model) scoring analysis that takes into account biophysical and geometrical constraints. As proof-of-concept cases, we demonstrate that APPRAISE can accurately classify receptor-dependent vs. receptor-independent adeno-associated viral vectors and diverse classes of engineered proteins such as miniproteins targeting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike, nanobodies targeting a G-protein-coupled receptor, and peptides that specifically bind to transferrin receptor or programmed death-ligand 1 (PD-L1). APPRAISE is accessible through a web-based notebook interface using Google Colaboratory (https://tiny.cc/APPRAISE). With its accuracy, interpretability, and generalizability, APPRAISE promises to expand the utility of protein structure prediction and accelerate protein engineering for biomedical applications.


Assuntos
Ligação Proteica , Engenharia de Proteínas , SARS-CoV-2 , Engenharia de Proteínas/métodos , Humanos , SARS-CoV-2/metabolismo , SARS-CoV-2/genética , Modelos Moleculares , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/química , Conformação Proteica , Anticorpos de Domínio Único/química , Anticorpos de Domínio Único/genética , Anticorpos de Domínio Único/metabolismo , Aprendizado Profundo , COVID-19/virologia , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/química , Dependovirus/genética , Vetores Genéticos/química , Vetores Genéticos/genética , Vetores Genéticos/metabolismo
4.
Development ; 148(6)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33593816

RESUMO

Cellular development and function rely on highly dynamic molecular interactions among proteins distributed in all cell compartments. Analysis of these interactions has been one of the main topics in cellular and developmental research, and has been mostly achieved by the manipulation of proteins of interest (POIs) at the genetic level. Although genetic strategies have significantly contributed to our current understanding, targeting specific interactions of POIs in a time- and space-controlled manner or analysing the role of POIs in dynamic cellular processes, such as cell migration or cell division, would benefit from more-direct approaches. The recent development of specific protein binders, which can be expressed and function intracellularly, along with advancement in synthetic biology, have contributed to the creation of a new toolbox for direct protein manipulations. Here, we have selected a number of short-tag epitopes for which protein binders from different scaffolds have been generated and showed that single copies of these tags allowed efficient POI binding and manipulation in living cells. Using Drosophila, we also find that single short tags can be used for POI manipulation in vivo.


Assuntos
Drosophila melanogaster/genética , Epitopos/genética , Peptídeos/genética , Proteínas/genética , Animais , Linhagem Celular , Células Cultivadas , Peptídeos/química , Ligação Proteica/genética , Proteínas/química , Biologia Sintética
5.
Small ; 20(19): e2308550, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38282057

RESUMO

Lithium-sulfur (Li-S) batteries, which store energy through reversible redox reactions with multiple electron transfers, are seen as one of the promising energy storage systems of the future due to their outstanding advantages. However, the shuttle effect, volume expansion, low conductivity of sulfur cathodes, and uncontrollable dendrite phenomenon of the lithium anodes have hindered the further application of Li-S batteries. In order to solve the problems and clarify the electrochemical reaction mechanism, various types of materials, such as metal compounds and carbon materials, are used in Li-S batteries. Polymers, as a class of inexpensive, lightweight, and electrochemically stable materials, enable the construction of low-cost, high-specific capacity Li-S batteries. Moreover, polymers can be multifunctionalized by obtaining rich structures through molecular design, allowing them to be applied not only in cathodes, but also in binders and solid-state electrolytes to optimize electrochemical performance from multiple perspectives. The most widely used areas related to polymer applications in Li-S batteries, including cathodes and electrolytes, are selected for a comprehensive overview, and the relevant mechanisms of polymer action in different components are discussed. Finally, the prospects for the practical application of polymers in Li-S batteries are presented in terms of advanced characterization and mechanistic analysis.

6.
Small ; : e2402581, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940389

RESUMO

In this work, the potential of bio-inspired strategies for the synthesis of calcium sulfate (CaSO4·nH2O) materials for heritage conservation is explored. For this, a nonclassical multi-step crystallization mechanism to understand the effect of calcein- a fluorescent chelating agent with a high affinity for divalent cations- on the nucleation and growth of calcium sulfate phases is proposed. Moving from the nano- to the macro-scale, this strategy sets the basis for the design and production of fluorescent nano-bassanite (NB-C; CaSO4·0.5H2O), with application as a fully compatible consolidant for the conservation of historic plasterwork. Once applied to gypsum (CaSO4·2H2O) plaster specimens, cementation upon hydration of nano-bassanite results in a significant increase in mechanical strength, while intracrystalline occlusion of calcein in newly-formed gypsum cement improves its weathering resistance. Furthermore, under UV irradiation, the luminescence produced by calcein molecules occluded in gypsum crystals formed upon nano-bassanite hydration allows the easy identification of the newly deposited consolidant within the treated gypsum plaster without altering the substrate's appearance.

7.
Brief Bioinform ; 23(5)2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-35580839

RESUMO

Human leukocyte antigens (HLA) regulate various innate and adaptive immune responses and play a crucial immunomodulatory role. Recent studies revealed that non-classical HLA-(HLA-E & HLA-G) based immunotherapies have many advantages over traditional HLA-based immunotherapy, particularly against cancer and COVID-19 infection. In the last two decades, several methods have been developed to predict the binders of classical HLA alleles. In contrast, limited attempts have been made to develop methods for predicting non-classical HLA binding peptides, due to the scarcity of sufficient experimental data. Of note, in order to facilitate the scientific community, we have developed an artificial intelligence-based method for predicting binders of class-Ib HLA alleles. All the models were trained and tested on experimentally validated data obtained from the recent release of IEDB. The machine learning models achieved more than 0.98 AUC for HLA-G alleles on validation dataset. Similarly, our models achieved the highest AUC of 0.96 and 0.94 on the validation dataset for HLA-E*01:01 and HLA-E*01:03, respectively. We have summarized the models developed in the past for non-classical HLA and validated the performance with the models developed in this study. Moreover, to facilitate the community, we have utilized our tool for predicting the potential non-classical HLA binding peptides in the spike protein of different variants of virus causing COVID-19, including Omicron (B.1.1.529). One of the major challenges in the field of immunotherapy is to identify the promiscuous binders or antigenic regions that can bind to a large number of HLA alleles. To predict the promiscuous binders for the non-classical HLA alleles, we developed a web server HLAncPred (https://webs.iiitd.edu.in/raghava/hlancpred) and standalone package.


Assuntos
Inteligência Artificial , COVID-19 , Sítios de Ligação , COVID-19/genética , Antígenos HLA-G/metabolismo , Humanos , Peptídeos/química , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/metabolismo
8.
Chemistry ; : e202402580, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373021

RESUMO

Selective control over crystallization in complex multicomponent systems such as hydrating cements is a key issue in modern material science. In this context, rational selection-based approaches appear highly promising in the quest for new additive chemistries. Here we have used phage display to identify peptide structures showing high affinity to adsorb on the surfaces of calcium sulfate hemihydrate (also referred to as bassanite), an important hydraulic binder employed in large scales by the construction industry. The results suggest a triplet of amino acids consisting of aspartic acid, serine and leucine, to maintain strong interactions with the surfaces of hemihydrate particles. This notion is confirmed by actual hydration experiments, in which the identified peptide motif provides strictly selective effects during the transformation of bassanite into more stable gypsum. Our work thus contributes to a better understanding of hydraulic binders and their required improvement for a sustainable future.

9.
Am J Nephrol ; 55(4): 450-462, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38555633

RESUMO

INTRODUCTION: Case reports have suggested a causative role between sevelamer use and subsequent gastrointestinal bleeding (GIB), but no large observational studies have evaluated this association. METHODS: Using the United States Renal Data System database from 2015 to 2019, we examined the association between initiation of sevelamer (vs. non-sevelamer containing phosphate binders) and GIB hospitalization as well as all-cause mortality among individuals on hemodialysis. We emulated a target trial using Cox regression models and inverse probability of treatment weights to estimate the adjusted hazard ratios (HR) across outcomes and subgroups. RESULTS: Among 21,354 new users of phosphate binders (11,276 sevelamer and 10,078 non-sevelamer) with baseline lab data (calcium, phosphorus, hemoglobin, and albumin), there were 2,811 GIB hospitalizations and 5,920 deaths after a median follow-up of 1.3 years. Compared with the initiation of non-sevelamer binders, sevelamer was not associated with an increased risk of GIB hospitalization (89 vs. 90 events per 1,000 person-years; IPTW-HR: 0.98, 95% CI: 0.91-1.06) or all-cause mortality (220 vs. 224 events per 1,000 person-years; IPTW-HR: 0.98, 95% CI: 0.93-1.03). Subgroup analyses (such as diabetes and anti-coagulation use) were generally consistent, and there was no association between sevelamer dose and GIB hospitalization. CONCLUSION: Among patients requiring hemodialysis, sevelamer (vs. non-sevelamer) containing phosphate binders was not associated with increased risk of GIB hospitalization.


Assuntos
Quelantes , Hemorragia Gastrointestinal , Hospitalização , Diálise Renal , Sevelamer , Humanos , Sevelamer/efeitos adversos , Sevelamer/uso terapêutico , Sevelamer/administração & dosagem , Diálise Renal/efeitos adversos , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/etiologia , Masculino , Feminino , Hospitalização/estatística & dados numéricos , Pessoa de Meia-Idade , Idoso , Quelantes/uso terapêutico , Quelantes/efeitos adversos , Falência Renal Crônica/terapia , Falência Renal Crônica/complicações , Falência Renal Crônica/mortalidade , Hiperfosfatemia/etiologia , Hiperfosfatemia/tratamento farmacológico
10.
Clin Transplant ; 38(1): e15156, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37812572

RESUMO

PROBLEM: Hyperkalemia is a serious condition among intra-abdominal transplant recipients, and the safety and efficacy of sodium zirconium cyclosilicate (SZC) for its management during the early post-transplant period are not well-established. METHODS: Adults who received at least one 10-g dose of SZC within 14 days after an intra-abdominal transplant between January 2020 and July 2022 were included in our study. The primary outcome was the change in potassium (K+) levels following the first SZC dose. Other analyses explored adjunctive potassium-lowering therapies, potential gastrointestinal complications, and patient subgroups based on therapy and transplant type. RESULTS: Among the recipients (n = 46), 11 were kidney recipients, 26 were liver recipients, seven were simultaneous liver/kidney recipients, and two were simultaneous pancreas/kidney recipients. The mean time to first dose post-transplant was 7.6 (±4) days, and the mean change in serum K+ after the initial SZC dose was -.27 mEq (p = .001). No gastrointestinal complications were observed following the SZC dose. The mean increase in serum bicarbonate was .58 mEq (p = .41) following the first dose of SZC. Four kidney recipients required dialysis following the SZC dose. CONCLUSION: This study represents the largest investigation on the use of SZC in transplant recipients. A single 10-g dose of SZC reduced serum K+ levels in all subgroups, while the use of adjunctive K+-lowering therapies did not provide additional reduction beyond the effects of SZC. Importantly, no gastrointestinal complications were observed. These findings suggest that SZC may be a safe and promising therapeutic option for hyperkalemia management following solid organ transplantation.


Assuntos
Hiperpotassemia , Potássio , Adulto , Humanos , Potássio/uso terapêutico , Hiperpotassemia/etiologia , Hiperpotassemia/tratamento farmacológico , Silicatos/uso terapêutico , Diálise Renal/efeitos adversos
11.
Artigo em Inglês | MEDLINE | ID: mdl-38289453

RESUMO

Hyperkalaemia is one of the most common electrolyte disorders in patients with cardiovascular disease (CVD). The true burden of hyperkalaemia in the real-world setting can be difficult to assess, but in population-based cohort studies up to 4 in 10 patients developed hyperkalaemia. In addition to drugs interfering with potassium metabolism and food intake, several conditions can cause or worsen hyperkalaemia, such as advanced age, diabetes, and chronic kidney disease. Mortality, cardiovascular morbidity, and hospitalisation are higher in patients with hyperkalaemia. Hyperkalaemia represents a major contraindication or a withholding cause for disease-modifying therapies like renin-angiotensin-aldosterone inhibitors (RAASi), mainly mineralocorticoid receptor antagonists. Hyperkalaemia can be also classified as acute and chronic, according to the onset. Acute hyperkalaemia is often a life-threatening emergency requiring immediate treatment to avoid lethal arrhythmias. Therapy goal is cell membrane stabilisation by calcium administration, cellular intake, shift of extracellular potassium to the intracellular space (insulin, beta-adrenergic agents, sodium bicarbonate), and increased elimination with diuretics or dialysis. Chronic hyperkalaemia was often managed with dietary counselling to prevent potassium-rich food intake and tapering of potassium-increasing drugs, mostly RAASi. Sodium polystyrene sulphonate, a potassium binder, was the only therapeutic option. Recently, new drugs such as patiromer and sodium zirconium cyclosilicate give new opportunities for the treatment of hyperkalaemia, as they proved to be safe, well tolerated, and effective. Aim of this review is to describe the burden of hyperkalaemia in cardiovascular patients, its direct and indirect effects, and the therapeutic options now available in the acute and chronic setting.

12.
Bioorg Chem ; 148: 107414, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38733748

RESUMO

Spectroscopic, biochemical, and computational modelling studies have been used to assess the binding capability of a set of minor groove binding (MGB) ligands against the self-complementary DNA sequences 5'-d(CGCACTAGTGCG)-3' and 5'-d(CGCAGTACTGCG)-3'. The ligands were carefully designed to target the DNA response element, 5'-WGWWCW-3', the binding site for several nuclear receptors. Basic 1D 1H NMR spectra of the DNA samples prepared with three MGB ligands show subtle variations suggestive of how each ligand associates with the double helical structure of both DNA sequences. The variations among the investigated ligands were reflected in the line shape and intensity of 1D 1H and 31P-{1H} NMR spectra. Rapid visual inspection of these 1D NMR spectra proves to be beneficial in providing valuable insights on MGB binding molecules. The NMR results were consistent with the findings from both UV DNA denaturation and molecular modelling studies. Both the NMR spectroscopic and computational analyses indicate that the investigated ligands bind to the minor grooves as antiparallel side-by-side dimers in a head-to-tail fashion. Moreover, comparisons with results from biochemical studies offered valuable insights into the mechanism of action, and antitumor activity of MGBs in relation to their structures, essential pre-requisites for future optimization of MGBs as therapeutic agents.


Assuntos
DNA , DNA/química , DNA/metabolismo , Ligantes , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Estrutura Molecular , Conformação de Ácido Nucleico , Sítios de Ligação , Relação Estrutura-Atividade , Modelos Moleculares , Relação Dose-Resposta a Droga , Espectroscopia de Ressonância Magnética , Linhagem Celular Tumoral
13.
Clin Exp Nephrol ; 28(9): 917-924, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38594468

RESUMO

BACKGROUND: Calcium supplements are commonly prescribed to prevent fractures in patients with osteoporosis. Nonetheless, they are generally eschewed in hemodialysis patients because they increase vascular calcification and induce cardiovascular disease. This retrospective cohort study aimed to investigate the effect of calcium-based phosphate binders (CBPB) on bone mineral density (BMD) in hemodialysis patients. METHODS: Outpatients on dialysis who underwent BMD measurement from January to December 2017, whose data on BMD trends and CBPB administration were recorded over the next 4 years, were enrolled. Patients receiving anti-osteoporotic medications were excluded. The association between the presence and duration of CBPB administration and changes in BMD was evaluated. RESULTS: The femoral neck's BMD decreased from 0.836 g/cm2 (0.702-0.952) to 0.764 g/cm2 (0.636-0.896) (P < 0.001) in the non-CBPB group (patients who never received CBPB over 4 years, n = 32). The CBPB group (n = 56) exhibited only a minute decrease from 0.833 g/cm2 (0.736-0.965) to 0.824 g/cm2 (0.706-0.939) (P = 0.004). Multivariate linear regression analysis revealed better BMD maintenance in the CBPB group [ß-coefficient (95% CI): 0.033 (0.001-0.065); P = 0.046] than in the non-CBPB group. Additionally, the prolonged-CBPB administration group showed superior BMD preservation [ß-coefficient (95% CI): 0.038 (0.001-0.076); P = 0.042]. CONCLUSION: CBPB administration may be associated with BMD maintenance.


Assuntos
Densidade Óssea , Diálise Renal , Humanos , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Densidade Óssea/efeitos dos fármacos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Colo do Fêmur/diagnóstico por imagem , Osteoporose/prevenção & controle , Osteoporose/etiologia , Fosfatos , Quelantes/uso terapêutico
14.
BMC Nephrol ; 25(1): 60, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378456

RESUMO

BACKGROUND: The consequences of chronic kidney disease (CKD) can be addressed with a range of pharmacotherapies primarily prescribed by nephrologists. More accurate information regarding future CKD-related pharmacotherapy requirements could guide clinical decisions including follow-up frequency. METHODS: Following assignment to derivation and validation groups (2,1), variables predicting individually future use of vitamin D receptor agonists (VDRA), phosphate binders, erythropoiesis stimulating agents (ESAs) and iron were identified using logistic regression in a prospective cohort study containing demography, comorbidity, hospitalization, laboratory, and mortality data in patients with CKD stage G4/G5 across six European countries. Discriminative ability was measured using C-statistics, and predicted probability of medication use used to inform follow-up frequency. RESULTS: A total of 2196 patients were included in the analysis. During a median follow-up of 735 days 648 initiated hemodialysis and 1548 did not. Combinations of age, diabetes status and iPTH, calcium, hemoglobin and serum albumin levels predicted the use of ESA, iron, phosphate binder or VDRA, with C-statistics of 0.70, 0.64, 0.73 and 0.63 in derivation cohorts respectively. Model performance in validation cohorts were similar. Sixteen percent of patients were predicted to have a likelihood of receiving any of these medications of less than 20%. CONCLUSIONS: In a multi-country CKD cohort, prediction of ESA and phosphate binder use over a two-year period can be made based on patient characteristics with the potential to reduce frequency of follow-up in individuals with low risk for requiring these medications.


Assuntos
Insuficiência Renal Crônica , Humanos , Estudos Prospectivos , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/epidemiologia , Diálise Renal , Ferro , Fosfatos
15.
Proc Natl Acad Sci U S A ; 118(34)2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34417313

RESUMO

When displayed on erythrocytes, peptides and proteins can drive antigen-specific immune tolerance. Here, we investigated a straightforward approach based on erythrocyte binding to promote antigen-specific tolerance to both peptides and proteins. We first identified a robust erythrocyte-binding ligand. A pool of one million fully d-chiral peptides was injected into mice, blood cells were isolated, and ligands enriched on these cells were identified using nano-liquid chromatography-tandem mass spectrometry. One round of selection yielded a murine erythrocyte-binding ligand with an 80 nM apparent dissociation constant, Kd We modified an 83-kDa bacterial protein and a peptide antigen derived from ovalbumin (OVA) with the identified erythrocyte-binding ligand. An administration of the engineered bacterial protein led to decreased protein-specific antibodies in mice. Similarly, mice given the engineered OVA-derived peptide had decreased inflammatory anti-OVA CD8+ T cell responses. These findings suggest that our tolerance-induction strategy is applicable to both peptide and protein antigens and that our in vivo selection strategy can be used for de novo discovery of robust erythrocyte-binding ligands.


Assuntos
Antígenos/genética , Antígenos/metabolismo , Eritrócitos/metabolismo , Engenharia de Proteínas/métodos , Animais , Antígenos/química , Linhagem Celular , Bases de Dados Factuais , Feminino , Tolerância Imunológica , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Ligação Proteica
16.
Chem Biodivers ; : e202400768, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980964

RESUMO

Bis-intercalators play a significant role in altering the DNA structure, affecting its stability, and potentially influencing various cellular processes. These compounds have gained considerable attention in medicinal chemistry and biochemistry due to their potential applications in cancer therapy, where they may interfere with DNA replication and transcription, leading to anticancer effects. Traditionally, these molecules often possess a high positive charge to enhance their affinity for the negatively charged DNA. However, due to a high positive charge, their cellular uptake is compromised, along with their enhanced potential off-target effects. In this study, we utilized bis-intercalator TOTO and replaced the charged linker segment (propane-1,3-diammonium) with a neutral peroxodisulphuric acid linker. Using molecular modeling and computer simulations (500 ns, 3 replicas), we investigated the potential of the designed molecule as a bis-intercalator and compared the properties with the control bis-intercalator bound to DNA. We observed that the designed bis-intercalator exhibited improved DNA binding (as assessed through MM-PBSA and Delphi methods) and membrane translocation permeability. With an overall reduced charge, significantly less off-target binding of the designed molecule is also anticipated. Consequently, bis-intercalators based on peroxodisulphuric linkers can potentially target DNA effectively, and their role in the future design of bis-intercalators is foreseen.

17.
Ren Fail ; 46(2): 2384585, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39252179

RESUMO

OBJECTIVES: Patients with end-stage renal disease (ESRD) on hemodialysis (HD) are at risk for hyperkalemia (HK), associated with cardiac arrhythmia and sudden death. Data on the burden of HK and management techniques among HD patients in China are still scarce. This study assessed the treatment modalities, recurrence, and prevalence of HK in Chinese HD patients. METHODS: In this prospective cohort study conducted from May 2021 to July 2022, patients aged ≥18 years who had ESRD and were on HD were enrolled from 15 centers in China (up to 6 months). RESULTS: Overall, 600 patients were enrolled. At the baseline visit, mean (± standard deviation) urea reduction ratio was 68.0% ± 9.70 and Kt/V was 1.45 ± 0.496. Over 6 months, 453 (75.5%) patients experienced HK, of whom 356 (78.6%) recurred. Within 1, 2, 3, 4, 5, and 6 months, 203 (44.8%), 262 (57.8%), 300 (66.2%), 326 (72.0%), 347 (76.6%), and 356 (78.6%) patients had at least one HK recurrence event, respectively. The proportions of patients with ≥1, 2, 3, 4, 5, or 6 HK recurrence events were 356 (78.6%), 306 (67.5%), 250 (55.2%), 208 (45.9%), 161 (35.5%), and 110 (24.3%), respectively. Among the 453 patients who experienced HK, only 24 (5.3%) were treated with potassium binders: seven (1.5%) with sodium polystyrene sulfonate, 13 (2.9%) with calcium polystyrene sulfonate, and six (1.3%) with sodium zirconium cyclosilicate. CONCLUSION: Since HK is a chronic illness, long-term care is necessary. Patients on HD should have effective potassium management on non-dialysis days, yet our real-world population rarely used potassium binders. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT04799067.


Assuntos
Hiperpotassemia , Falência Renal Crônica , Diálise Renal , Humanos , Hiperpotassemia/etiologia , Hiperpotassemia/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Diálise Renal/efeitos adversos , China/epidemiologia , Falência Renal Crônica/terapia , Falência Renal Crônica/complicações , Idoso , Adulto , Poliestirenos/uso terapêutico , Poliestirenos/efeitos adversos , Silicatos/uso terapêutico , Recidiva , Potássio/sangue , Prevalência , População do Leste Asiático
18.
Int J Mol Sci ; 25(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38791537

RESUMO

Many years of foundry practice and much more accurate analytical methods have shown that sands with organic binders, in addition to their many technological advantages, pose risks associated with the emission of many compounds, including harmful ones (e.g., formaldehyde, phenol, benzene, polycyclic aromatic hydrocarbons, and sulfur), arising during the pouring of liquid casting alloys into molds, their cooling, and knock-out. The aim of this research is to demonstrate the potential benefits of adopting inorganic binders in European iron foundries. This will improve the environmental and working conditions by introducing cleaner and more ecological production methods, while also ranking the tested binders studied in terms of their harmful content. The article pays special attention to the analysis of seven innovative inorganic binders and one organic binder, acting as a reference for emissions of gases from the BTEX (benzene, toluene, ethylbenzene, and xylenes) and PAHs (polycyclic aromatic hydrocarbons) groups and other compounds such as phenol, formaldehyde, and isocyanates (MDI and TDI) generated during the mold pouring process with liquid metals. The knowledge gained will, for the first time, enrich the database needed to update the Reference Document on The Best Available Techniques for the Smitheries and Foundries Industry (SF BREF).


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Compostos Inorgânicos/química , Metalurgia , Formaldeído/química
19.
Molecules ; 29(18)2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39339439

RESUMO

Human Carbonic Anhydrases (hCA) are enzymes that contribute to cancer's development and progression. Isoforms IX and XII have been identified as potential anticancer targets, and, more specifically, hCA IX is overexpressed in hypoxic tumor cells, where it plays an important role in reprogramming the metabolism. With the aim to find new inhibitors towards IX and XII isoforms, the hybridization of the privileged scaffolds isatin, dihydrothiazole, and benzenesulfonamide was investigated in order to explore how it may affect the activity and selectivity of the hCA isoforms. In this respect, a series of isatin thiazolidinone hybrids have been designed and synthesized and their biological activity and selectivity on hCA I, hCA II, hCA IX, and hCA XII explored. The new compounds exhibited promising inhibitory activity results on isoforms IX and XII in the nanomolar range, which has highlighted the importance of substituents in the isatin ring and in position 3 and 5 of thiazolidinone. In particular, compound 5g was the most active toward hCA IX, while 5f was the most potent inhibitor of hCA XII within the series. When both potency and selectivity were considered, compound 5f appeared as one of the most promising. Additionally, our investigations were supported by molecular docking experiments, which have highlighted the putative binding poses of the most promising compound.


Assuntos
Inibidores da Anidrase Carbônica , Anidrases Carbônicas , Desenho de Fármacos , Simulação de Acoplamento Molecular , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/farmacologia , Inibidores da Anidrase Carbônica/síntese química , Humanos , Anidrases Carbônicas/química , Anidrases Carbônicas/metabolismo , Relação Estrutura-Atividade , Anidrase Carbônica IX/antagonistas & inibidores , Anidrase Carbônica IX/metabolismo , Anidrase Carbônica IX/química , Estrutura Molecular , Isatina/química , Isatina/farmacologia , Isatina/análogos & derivados
20.
Molecules ; 29(16)2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39202914

RESUMO

Asphalt binder is the most common material used in road construction. However, the need for more durable and safer pavements requires a better understanding of asphalt's aging mechanisms and how its characteristics can be improved. The current challenge for the road industry is to use renewable materials (i.e., biomaterials not subjected to depletion) as a partial replacement for petroleum-based asphalt, which leads to reducing the carbon footprint. The most promising is to utilize biomaterials following the principles of sustainability in the modification of the asphalt binder. However, to understand whether the application of renewable materials represents a reliable and viable solution or just a research idea, this review covers various techniques for extracting bio-oil and preparing bio-modified asphalt binders, technical aspects including physical properties of different bio-oils, the impact of bio-oil addition on asphalt binder performance, and the compatibility of bio-oils with conventional binders. Key findings indicate that bio-oil can enhance modified asphalt binders' low-temperature performance and aging resistance. However, the effect on high-temperature performance varies based on the bio-oil source and preparation method. The paper concludes that while bio-oils show promise as renewable modifiers for asphalt binders, further research is needed to optimize their use and fully understand their long-term performance implications.

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