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1.
Vet Med Sci ; 10(4): e1528, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38952268

RESUMO

BACKGROUND: Acute flaccid paralysis (AFP) is a complex clinical syndrome with various aetiologies. If untreated, AFP may lead to death due to failure of respiratory muscles. Tick paralysis, which is a noninfectious neurologic syndrome of AFP, occurs following tick attachment, engorgement, and injection of tick saliva toxins. There is no specific diagnostic test for tick paralysis, and mortality increases as definitive diagnosis is delayed. Although metabolomic investigation of tick saliva was conducted, there is a lack of research on metabolomic evaluation of hosts affected by tick paralysis. OBJECTIVES: Thus, the aim of this study is to investigate metabolomic changes in serum samples of dogs with tick paralysis due to Rhipicephalus sanguineus using NMR-based metabolomics and to identify potential diagnostic/prognostic markers. MATERIALS AND METHODS: Forty dogs infested with R. sanguineus, with clinical findings compatible with AFP and with a confirmed tick paralysis diagnosis ex juvantibus, constituted the Paralysis Group. Ten healthy dogs, which were admitted either for vaccination and/or check-up purposes, constituted the Control Group. After the confirmation tick paralysis, medical history, vaccination and nutritional status, body surface area and estimated tick numbers of all the dogs were noted. Physical examination included body temperature, heart and respiratory rate, capillary refill time evaluation and Modified Glasgow Coma Scale calculation. Serum samples were extracted from venous blood samples of all the dogs and were prepared for NMR analysis, and NMR-based metabolomics identification and quantification were performed. RESULTS: NMR-based serum metabolomics of the present study revealed distinct up/down-regulated expressions, presenting a promising avenue. Moreover, it was observed that energy metabolism and especially liver functions were impaired in dogs with tick paralysis, and not only the respiratory system but also the kidneys were affected. CONCLUSION: It was concluded that the present approach may help to better understand the pathological mechanisms developing in cases of AFP due to tick paralysis.


Assuntos
Doenças do Cão , Espectroscopia de Ressonância Magnética , Metabolômica , Paralisia por Carrapato , Animais , Cães , Paralisia por Carrapato/veterinária , Paralisia por Carrapato/complicações , Doenças do Cão/metabolismo , Doenças do Cão/parasitologia , Doenças do Cão/diagnóstico , Feminino , Masculino , Rhipicephalus sanguineus/fisiologia , Metaboloma , Paralisia/veterinária , Paralisia/etiologia
3.
Methods Enzymol ; 700: 295-328, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38971604

RESUMO

The specific spatial and temporal distribution of lipids in membranes play a crucial role in determining the biochemical and biophysical properties of the system. In nature, the asymmetric distribution of lipids is a dynamic process with ATP-dependent lipid transporters maintaining asymmetry, and passive transbilayer diffusion, that is, flip-flop, counteracting it. In this chapter, two probe-free techniques, 1H NMR and time-resolved small angle neutron scattering, are described in detail as methods of investigating lipid flip-flop rates in synthetic liposomes that have been generated with an asymmetric bilayer composition.


Assuntos
Bicamadas Lipídicas , Lipossomos , Difração de Nêutrons , Espalhamento a Baixo Ângulo , Lipossomos/química , Bicamadas Lipídicas/química , Difração de Nêutrons/métodos , Espectroscopia de Prótons por Ressonância Magnética/métodos
4.
Food Chem ; 458: 140093, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38943960

RESUMO

This study evaluated the effects of postharvest ripening (0-6 days, D0-6) on cell wall pectin profile, infrared-assisted hot air-drying characteristics, and sugar content. Results showed that during postharvest ripening progress, the content of water-soluble pectin (WSP) and chelate-soluble pectin (CSP) increased while the content of Na2CO3-soluble pectin (NSP) and hemicellulose (HC) decreased. In addition, the average molecular weight of WSP increased while the average molecular weight of NSP decreased. Secondly, the drying time of plums with different postharvest ripening periods was in the order: D3 < D4 < D2 < D1 < D0 < D5 < D6. Furthermore, the sugar content of dried plums was mainly influenced by drying time, with three stages of sugar changes observed, tied to moisture content: (1) Sucrose hydrolyzes (50-85%); (2) Fructose and glucose degrade (15-50%); (3) Sorbitol degrades (15-42%). These findings indicate that the transformation of cell wall pectin profile during the postharvest ripening process alters drying behavior and regulates the sugar content of dried plums. CHEMICAL COMPOUNDS STUDIED IN THIS ARTICLE: Galacturonic acid (PubChem CID: 439215); Acetone (PubChem CID: 180); Distilled water (PubChem CID: 962); Trans-1,2-Diaminocyclohexane-N, N, N, N'-tetraacetic acid (PubChem CID: 2723845); Na2CO3 (PubChem CID: 10340); Glucose (PubChem CID: 5793); fructose (PubChem CID: 2723872) sucrose (PubChem CID: 5988) sorbitol (PubChem CID: 5780) and Sodium borohydride (PubChem CID: 4311764).

5.
bioRxiv ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38915483

RESUMO

Intrinsically disordered protein regions (IDRs) are well-established as contributors to intermolecular interactions and the formation of biomolecular condensates. In particular, RNA-binding proteins (RBPs) often harbor IDRs in addition to folded RNA-binding domains that contribute to RBP function. To understand the dynamic interactions of an IDR-RNA complex, we characterized the RNA-binding features of a small (68 residues), positively charged IDR-containing protein, SERF. At high concentrations, SERF and RNA undergo charge-driven associative phase separation to form a protein- and RNA-rich dense phase. A key advantage of this model system is that this threshold for demixing is sufficiently high that we could use solution-state biophysical methods to interrogate the stoichiometric complexes of SERF with RNA in the one-phase regime. Herein, we describe our comprehensive characterization of SERF alone and in complex with a small fragment of the HIV-1 TAR RNA (TAR) with complementary biophysical methods and molecular simulations. We find that this binding event is not accompanied by the acquisition of structure by either molecule; however, we see evidence for a modest global compaction of the SERF ensemble when bound to RNA. This behavior likely reflects attenuated charge repulsion within SERF via binding to the polyanionic RNA and provides a rationale for the higher-order assembly of SERF in the context of RNA. We envision that the SERF-RNA system will lower the barrier to accessing the details that support IDR-RNA interactions and likewise deepen our understanding of the role of IDR-RNA contacts in complex formation and liquid-liquid phase separation.

6.
Sci Rep ; 14(1): 14806, 2024 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926483

RESUMO

Multiple sclerosis (MS) is a chronic and progressive neurological disorder, characterized by neuroinflammation and demyelination within the central nervous system (CNS). The etiology and the pathogenesis of MS are still unknown. Till now, no satisfactory treatments, diagnostic and prognostic biomarkers are available for MS. Therefore, we aimed to investigate metabolic alterations in patients with MS compared to controls and across MS subtypes. Metabolic profiles of serum samples from patients with MS (n = 90) and healthy control (n = 30) were determined by Nuclear Magnetic Resonance (1H-NMR) Spectroscopy using cryogenic probe. This approach was also utilized to identify significant differences between the metabolite profiles of the MS groups (primary progressive, secondary progressive, and relapsing-remitting) and the healthy controls. Concentrations of nine serum metabolites (adenosine triphosphate (ATP), tryptophan, formate, succinate, glutathione, inosine, histidine, pantothenate, and nicotinamide adenine dinucleotide (NAD)) were significantly higher in patients with MS compared to control. SPMS serum exhibited increased pantothenate and tryptophan than in PPMS. In addition, lysine, myo-inositol, and glutamate exhibited the highest discriminatory power (0.93, 95% CI 0.869-0.981; 0.92, 95% CI 0.859-0.969; 0.91, 95% CI 0.843-0.968 respectively) between healthy control and MS. Using NMR- based metabolomics, we identified a set of metabolites capable of classifying MS patients and controls. These findings confirmed untargeted metabolomics as a useful approach for the discovery of possible novel biomarkers that could aid in the diagnosis of the disease.


Assuntos
Biomarcadores , Progressão da Doença , Espectroscopia de Ressonância Magnética , Metabolômica , Esclerose Múltipla , Humanos , Biomarcadores/sangue , Masculino , Feminino , Metabolômica/métodos , Adulto , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Esclerose Múltipla/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Metaboloma , Estudos de Casos e Controles
7.
Metabolites ; 14(6)2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38921465

RESUMO

Cannabichromene (CBC) is a minor cannabinoid within the array of over 120 cannabinoids identified in the Cannabis sativa plant. While CBC does not comprise a significant portion of whole plant material, it is available to the public in a purified and highly concentrated form. As minor cannabinoids become more popular due to their potential therapeutic properties, it becomes crucial to elucidate their metabolism in humans. Therefore, the goal of this was study to identify the major CBC phase I-oxidized metabolite generated in vitro following incubation with human liver microsomes. The novel metabolite structure was identified as 2'-hydroxycannabicitran using gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy. Following the identification, in silico molecular modeling experiments were conducted and predicted 2'-hydroxycannabicitran to fit in the orthosteric site of both the CB1 and CB2 receptors. When tested in vitro utilizing a competitive binding assay, the metabolite did not show significant binding to either the CB1 or CB2 receptors. Further work necessitates the determination of potential activity of CBC and the here-identified phase I metabolite in other non-cannabinoid receptors.

8.
Clin Chim Acta ; 561: 119834, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944409

RESUMO

BACKGROUND: This study aims to identify metabolomic signatures in uterine fluid of women with idiopathic recurrent spontaneous miscarriage (IRSM) during window of implantation (WOI). Also, glucose transporters GLUT3 and GLUT4 and proteins of PI3K-Akt signaling pathway in endometrial tissue are assessed. METHODS: Paired uterine fluid and endometrial biopsies were collected during WOI from women with IRSM (n = 24) and healthy women with azoospermic male partners as controls (n = 15). NMR metabolomics was used to identify the dysregulated metabolites in uterine fluid of IRSM women. Additionally, proteins and glucose transporters were investigated in the endometrial tissue using immunohistochemistry (IHC) and western blotting. RESULTS: Uterine fluid metabolomics indicated eleven metabolites to be significantly downregulated in IRSM. While expression levels of PI3K (p85), PI3K (p110), p-Akt (Thr308), p-Akt (Ser473), GLUT3 and GLUT4 were significantly downregulated in endometrial tissue of these women, p-IKK α/ß (Ser176/180) and p-NFkBp65 (Ser536) were significantly increased. CONCLUSION: Our findings suggest that dysregulation of PI3K/Akt pathway in the uterine microenvironment could be a likely cause of endometrial dysfunction, thereby affecting implantation. Further studies on the downstream effects of the Akt signaling pathway in-vitro for improved understanding of the Akt-mediated cellular responses in IRSM is, therefore, warranted.

9.
Toxicology ; 506: 153871, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38925359

RESUMO

Fmr1 (fragile X messenger ribonucleoprotein 1)-knockout (KO) rats, modeling the human Fragile X Syndrome (FXS), are of particular interest for exploring the ASD-like phenotype in preclinical studies. Gestational exposure to chlorpyrifos (CPF) has been associated with ASD diagnosis in humans and ASD-like behaviors in rodents and linked to the microbiota-gut-brain axis. In this study, we have used both Fmr1-KO and wild-type male rats (F2 generation) at postnatal days (PND) 7 and 40 obtained after F1 pregnant females were randomly exposed to 1 mg/kg/mL/day of CPF or vehicle. A nuclear magnetic resonance (NMR) metabolomics approach together with gene expression profiles of these F2 generation rats were employed to analyze different brain regions (such as prefrontal cortex, hippocampus, and cerebellum), whole large intestine (at PND7) and gut content (PND40). The statistical comparison of each matrix spectral profile unveiled tissue-specific metabolic fingerprints. Significant variations in some biomarker levels were detected among brain tissues of different genotypes, including taurine, myo-inositol, and 3-hydroxybutyric acid, and exposure to CPF induced distinct metabolic alterations, particularly in serine and myo-inositol. Additionally, this study provides a set of metabolites associated with gastrointestinal dysfunction in ASD, encompassing several amino acids, choline-derived compounds, bile acids, and sterol molecules. In terms of gene expression, genotype and gestational exposure to CPF had only minimal effects on decarboxylase 2 (gad2) and cholinergic receptor muscarinic 2 (chrm2) genes.

10.
J Biol Chem ; 300(7): 107457, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38866324

RESUMO

AT-rich interacting domain (ARID)-containing proteins, Arids, are a heterogeneous DNA-binding protein family involved in transcription regulation and chromatin processing. For the member Arid5a, no exact DNA-binding preference has been experimentally defined so far. Additionally, the protein binds to mRNA motifs for transcript stabilization, supposedly through the DNA-binding ARID domain. To date, however, no unbiased RNA motif definition and clear dissection of nucleic acid-binding through the ARID domain have been undertaken. Using NMR-centered biochemistry, we here define the Arid5a DNA preference. Further, high-throughput in vitro binding reveals a consensus RNA-binding motif engaged by the core ARID domain. Finally, transcriptome-wide binding (iCLIP2) reveals that Arid5a has a weak preference for (A)U-rich regions in pre-mRNA transcripts of factors related to RNA processing. We find that the intrinsically disordered regions flanking the ARID domain modulate the specificity and affinity of DNA binding, while they appear crucial for RNA interactions. Ultimately, our data suggest that Arid5a uses its extended ARID domain for bifunctional gene regulation and that the involvement of IDR extensions is a more general feature of Arids in interacting with different nucleic acids at the chromatin-mRNA interface.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38870260

RESUMO

CONTEXT: Patients with nonfunctioning adenomas (NFA), adenomas with mild autonomous cortisol secretion (MACS) and Cushing syndrome (CS) demonstrate an increased cardiovascular risk. OBJECTIVE: To determine the extent of lipoprotein abnormalities in NFA, MACS, and CS. METHODS: We conducted a single-center cross-sectional study of patients with NFA (n = 167), MACS (n = 213), CS (n = 142) and referent subjects (n = 202) between January 2015 and July 2022. Triglyceride-rich lipoprotein particles (TRLP), low density lipoprotein particles (LDLP), high density lipoprotein particles (HDLP), their subclasses and sizes were measured using nuclear magnetic resonance spectroscopy. Multivariable logistic analyses were adjusted for age, sex, BMI, smoking, hypertension, diabetes and lipid lowering drug therapy. RESULTS: In age- and sex-adjusted analysis, all patients categories demonstrated increased very large TRLP, large TRLP and greater TRL size (odds ratio (OR) ranging from 1.22 to 2.08) and total LDLP (OR ranging from 1.22 to 1.75) and decreased LDL and HDL size compared to referent subjects. In fully adjusted analysis, LDLP concentrations remained elevated in all patient categories (odds ratios ranging from 1.31 to 1.84). Total cholesterol, LDL cholesterol, triglycerides and apolipoprotein B were also higher in all patient categories in age- and sex-adjusted analysis with apoB remaining elevated in all patient categories in fully adjusted analysis. Similar LDLP and apoB elevations were observed in all patient categories after excluding subjects on lipid lowering therapy. CONCLUSION: Patients with overt, mild, and even absent cortisol excess demonstrate lipoprotein profile abnormalities, in particular, high LDLP and apoB concentrations, which conceivably contribute to high cardiometabolic risk.

12.
Food Res Int ; 188: 114415, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823855

RESUMO

Several scientific studies have warned that the ingestion of dietary lipid oxidation products (LOPs) may initiate or exacerbate the development of several chronic non-communicable diseases in humans. Indeed, the constantly increasing consumption of culinary oils by larger global populations indicates the need for scientific techniques to suppress the evolution of LOPs in thermo-oxidised oils. This study employed a 600.13 MHz frequency NMR spectrometer in evaluating the effect of 10, 50, and 100 ppm concentrations of chemical compounds reported to have antioxidant properties in continuously-stirred and thermally stressed polyunsaturated fatty acid (PUFA)-rich hemp seed oil at a frying temperature of 180℃ for 180 min. Research data acquired showed that the antioxidants α- and γ-tocopherol, γ-oryzanol, ß-carotene, eugenol, resveratrol, ascorbyl palmitate, gentisic acid, and L-ascorbic acid all played a vital role in suppressing the evolution of secondary aldehydic lipid oxidation products in hemp seed oil. However, the most ineffective LOP-suppressing agent was L-lysine, an observation which may be accountable by its poor oil solubility. Nonetheless, trends deduced for compounds acting as antioxidants were mainly unique for each class of agent tested. Conversely, the antioxidant capacity of resveratrol was consistently higher, and this effect was found to be independent of its added amounts. This report provides a direct approach in developing scientific methods for the suppression of LOPs in thermo-oxidatively susceptible PUFA-rich cooking oils.


Assuntos
Antioxidantes , Cannabis , Temperatura Alta , Peroxidação de Lipídeos , Óleos de Plantas , Antioxidantes/química , Óleos de Plantas/química , Cannabis/química , Peroxidação de Lipídeos/efeitos dos fármacos , Culinária , Sementes/química , Resveratrol/química , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/química , Espectroscopia de Ressonância Magnética , Ácido Ascórbico/química , Extratos Vegetais
13.
Environ Monit Assess ; 196(7): 595, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833198

RESUMO

Aquatic humic substances (AHS) are defined as an important components of organic matter, being composed as small molecules in a supramolecular structure and can interact with metallic ions, thereby altering the bioavailability of these species. To better understand this behavior, AHS were extracted and characterized from Negro River, located near Manaus city and Carú River, that is situated in Itacoatiara city, an area experiencing increasing anthropogenic actions; both were characterized as blackwater rivers. The AHS were characterized by 13C nuclear magnetic ressonance and thermochemolysis GC-MS to obtain structural characteristics. Interaction studies with Cu (II), Al (III), and Fe (III) were investigated using fluorescence spectroscopy applied to parallel factor analysis (PARAFAC) and two-dimensional correlation spectroscopy with Fourier transform infrared spectroscopy (2D-COS FTIR). The AHS from dry season had more aromatic fractions not derived from lignin and had higher content of alkyls moities from microbial sources and vegetal tissues of autochthonous origin, while AHS isolated in the rainy season showed more metals in its molecular architecture, lignin units, and polysacharide structures. The study showed that AHS composition from rainy season were able to interact with Al (III), Fe (III), and Cu (II). Two fluorescent components were identified as responsible for interaction: C1 (blue-shifted) and C2 (red-shifted). C1 showed higher complexation capacities but with lower complexation stability constants (KML ranged from 0.3 to 7.9 × 105) than C2 (KML ranged from 3.1 to 10.0 × 105). 2D-COS FTIR showed that the COO- and C-O in phenolic were the most important functional groups for interaction with studied metallic ions.


Assuntos
Alumínio , Cobre , Monitoramento Ambiental , Substâncias Húmicas , Rios , Estações do Ano , Poluentes Químicos da Água , Substâncias Húmicas/análise , Rios/química , Espectroscopia de Infravermelho com Transformada de Fourier , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Cobre/análise , Alumínio/análise , Alumínio/química , Ferro/análise , Ferro/química , Brasil , Análise Fatorial
14.
bioRxiv ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38853912

RESUMO

The Tropomyosin 1 isoform I/C C-terminal domain (Tm1-LC) fibril structure is studied jointly with cryogenic electron microscopy (cryo-EM) and solid state nuclear magnetic resonance (NMR). This study demonstrates the complementary nature of these two structural biology techniques. Chemical shift assignments from solid state NMR are used to determine the secondary structure at the level of individual amino acids, which is faithfully seen in cryo-EM reconstructions. Additionally, solid state NMR demonstrates that the region not observed in the reconstructed cryo-EM density is primarily in a highly mobile random coil conformation rather than adopting multiple rigid conformations. Overall, this study illustrates the benefit of investigations combining cryo-EM and solid state NMR to investigate protein fibril structure.

15.
Eur J Sport Sci ; 24(6): 721-731, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38874966

RESUMO

It has been assumed that exercise intensity variation throughout a cycling time trial (TT) occurs in alignment of various metabolic changes to prevent premature task failure. However, this assumption is based on target metabolite responses, which limits our understanding of the complex interconnection of metabolic responses during exercise. The current study characterized the metabolomic profile, an untargeted metabolic analysis, after specific phases of a cycling 4-km TT. Eleven male cyclists performed three separated TTs in a crossover counterbalanced design, which were interrupted at the end of the fast-start (FS, 600 ± 205 m), even-pace (EP, 3600 ± 190 m), or end-spurt (ES, 4000 m) phases. Blood samples were taken before any exercise and 5 min after exercise cessation, and the metabolomic profile characterization was performed using Nuclear Magnetic Resonance metabolomics. Power output (PO) was also continually recorded. There were higher PO values during the FS and ES compared to the EP (all p < 0.05), which were accompanied by distinct metabolomic profiles. FS showed high metabolite expression in TCA cycle and its related pathways (e.g., glutamate, citric acid, and valine metabolism); whereas, the EP elicited changes associated with antioxidant effects and oxygen delivery adjustment. Finally, ES was related to pathways involved in NAD turnover and serotonin metabolism. These findings suggest that the specific phases of a cycling TT are accompanied by distinct metabolomic profiles, providing novel insights regarding the relevance of specific metabolic pathways on the process of exercise intensity regulation.


Assuntos
Ciclismo , Estudos Cross-Over , Metaboloma , Humanos , Masculino , Metaboloma/fisiologia , Adulto , Ciclismo/fisiologia , Ciclo do Ácido Cítrico , Serotonina/sangue , NAD/sangue , NAD/metabolismo , Adulto Jovem , Ácido Glutâmico/sangue , Ácido Glutâmico/metabolismo , Metabolômica , Valina/sangue , Ácido Cítrico/sangue
16.
J Magn Reson ; 364: 107711, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38879928

RESUMO

In the design of ultrahigh field nuclear magnetic resonance (NMR) superconducting magnets, it typically requires a high homogeneous magnetic field in the diameter of spherical volume (DSV) to obtain high spectrum resolution. However, shimming technique presents challenges due to the magnet bore space limitations, as accurate measurement of magnetic field distribution is very difficult, especially for customized micro-bore magnets. In this study, we introduced an active shimming method that utilized iterative adjustment of shim coil currents to improve the magnetic field homogeneity based on the full width at half maximum (FWHM) of the spectrum. The proposed method can determine the optimal set of currents for shim coils, effectively enhancing spatial field homogeneity by converging the FWHM. Experimental validation on a 25 T NMR superconducting magnet demonstrated the efficacy of the proposed method. Specifically, the active shimming method improved the field homogeneity of a 10 mm DSV from 7.09 ppm to 2.27 ppm with only four shim coils, providing a superior magnetic field environment for solid NMR and further magnetic resonance imaging (MRI) experiment. Furthermore, the proposed method can be promoted to more customized micro-bore magnets that require high magnetic field homogeneity.

17.
Adv Exp Med Biol ; 1441: 435-458, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38884724

RESUMO

Over the last few decades, the study of congenital heart disease (CHD) has benefited from various model systems and the development of molecular biological techniques enabling the analysis of single gene as well as global effects. In this chapter, we first describe different models including CHD patients and their families, animal models ranging from invertebrates to mammals, and various cell culture systems. Moreover, techniques to experimentally manipulate these models are discussed. Second, we introduce cardiac phenotyping technologies comprising the analysis of mouse and cell culture models, live imaging of cardiogenesis, and histological methods for fixed hearts. Finally, the most important and latest molecular biotechniques are described. These include genotyping technologies, different applications of next-generation sequencing, and the analysis of transcriptome, epigenome, proteome, and metabolome. In summary, the models and technologies presented in this chapter are essential to study the function and development of the heart and to understand the molecular pathways underlying CHD.


Assuntos
Cardiopatias Congênitas , Animais , Humanos , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/metabolismo , Modelos Animais de Doenças , Camundongos , Fenótipo , Sequenciamento de Nucleotídeos em Larga Escala , Técnicas de Cultura de Células/métodos
18.
Structure ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38889720

RESUMO

Disulfide-rich peptides such as defensins play diverse roles in immunity and ion channel modulation, as well as constituting the bioactive components of many animal venoms. We investigated the structure and bioactivity of U-RDTX-Pp19, a peptide previously discovered in venom of the assassin bug Pristhesancus plagipennis. Recombinant Pp19 (rPp19) was found to possess insecticidal activity when injected into Drosophila melanogaster. A bioinformatic search revealed that domains homologous to Pp19 are produced by assassin bugs and diverse other arthropods. rPp19 co-eluted with native Pp19 isolated from P. plagipennis, which we found is more abundant in hemolymph than venom. We solved the three-dimensional structure of rPp19 using 2D 1H NMR spectroscopy, finding that it adopts a disulfide-stabilized structure highly similar to known trans-defensins, with the same cystine connectivity as human α-defensin (I-VI, II-IV, and III-V). The structure of Pp19 is unique among reported structures of arthropod peptides.

19.
ChemSusChem ; : e202301962, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896830

RESUMO

This study explores the properties of aprotic electrolytes via the application of experimental methods, including nuclear magnetic resonance spectroscopy and electrochemical techniques, along with molecular dynamic modeling. The aim is to provide a quantitative description of the physico-chemical properties of two well-established electrolytes (case studies), each exhibiting significantly distinct dielectric properties: a LiTFSI (Lithium bis(trifluoromethanesulfonyl)imide) solution in dimethyl sulfoxide (DMSO, dielectric constant = 46.68) and a LiTFSI solution in tetraethylene glycol dimethyl ether (TEGDME, =7.71). We obtained a comprehensive insight into the properties of the electrolytes at both the macroscopic-collective and molecular levels with particular emphasis on the interactions between the Li ions and solvent molecules. We discovered remarkable disparities in the structural arrangements, solvation behaviors, and bulk-related properties of these electrolyte systems, particularly in response to temperature changes.

20.
J Magn Reson ; 364: 107710, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38901172

RESUMO

Motionally averaged dipolar couplings are an important tool for understanding the complex dynamics of catalysts, polymers, and biomolecules. While there is a plethora of solid-state NMR pulse sequences available for their measurement, in can be difficult to gauge the methods' strengths and weaknesses. In particular, there has not been a comprehensive comparison of their performance in natural abundance samples, where 1H homonuclear dipolar couplings are important and the use of large MAS rotors may be required for sensitivity reasons. In this work, we directly compared some of the more common methods for measuring C-H dipolar couplings in natural abundance samples using L-alanine (L-Ala) and the N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLF) tripeptide as model systems. We evaluated their performance in terms of accuracy, resolution, sensitivity, and ease of implementation. We found that, despite the presence of 1H homonuclear dipolar interactions, all methods, with the exception of REDOR, were able to yield the reasonable dipolar coupling strengths for both mobile and static moieties. Of these methods, PDLF provides the most convenient workflow and precision at the expense of low sensitivity. In low-sensitivity cases, MAS-PISEMA and DIPSHIFT appear to be the better options.

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