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1.
Biophys Chem ; 310: 107254, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38728809

RESUMO

High isotropic resolution is essential for the structural elucidation of samples with multiple sites. In this study, utilizing the benefits of TRAPDOR-based heteronuclear multiple quantum coherence (T-HMQC) and a pair of one rotor period long cosine amplitude modulated low-power (cos-lp) pulse-based symmetric-split-t1 multiple-quantum magic angle spinning (MQMAS) methods, we have developed a proton-detected 2D 35Cl/1H T-HMQC-MQMAS pulse sequence under fast MAS (70 kHz) to achieve high-resolution in the indirect dimension of the spin-3/2 (35Cl) nuclei connected via protons. As T-HMQC polarizes not only single-quantum central transition (SQCT) but also triple-quantum (TQ) coherences, the proposed 2D pulse sequence is implemented via selection of two coherence pathways (SQCT→TQ →SQCT and TQ → SQCT→TQ) resulting in the 35Cl isotropic dimension and is superior to the existing double-quantum satellite-transition (DQST) T-HMQC in terms of resolution.


Assuntos
Ressonância Magnética Nuclear Biomolecular , Teoria Quântica
2.
ACS Chem Neurosci ; 15(5): 916-931, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38369717

RESUMO

Novel insights into the etiology of metabolic disorders have recently been uncovered through the study of metabolite amyloids. In particular, inborn errors of metabolism (IEMs), including gout, Lesch-Nyhan syndrome (LNS), xanthinuria, citrullinemia, and hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome, are attributed to the dysfunction of the urea cycle and uric acid pathway. In this study, we endeavored to understand and mechanistically characterize the aggregative property exhibited by the principal metabolites of the urea cycle and uric acid pathway, specifically hypoxanthine, xanthine, citrulline, and ornithine. Employing scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM), we studied the aggregation profiles of the metabolites. Insights obtained through molecular dynamics (MD) simulation underscore the vital roles of π-π stacking and hydrogen bonding interactions in the self-assembly process, and thioflavin T (ThT) assays further corroborate the amyloid nature of these metabolites. The in vitro MTT assay revealed the cytotoxic trait of these assemblies, a finding that was substantiated by in vivo assays employing the Caenorhabditis elegans (C. elegans) model, which revealed that the toxic effects were more pronounced and dose-specific in the case of metabolites that had aged via longer preincubation. We hence report a compelling phenomenon wherein these metabolites not only aggregate but transform into a soft, ordered assembly over time, eventually crystallizing upon extended incubation, leading to pathological implications. Our study suggests that the amyloidogenic nature of the involved metabolites could be a common etiological link in IEMs, potentially providing a unified perspective to study their pathophysiology, thus offering exciting insights into the development of targeted interventions for these metabolic disorders.


Assuntos
Hiperamonemia , Ornitina/deficiência , Distúrbios Congênitos do Ciclo da Ureia , Ácido Úrico , Animais , Caenorhabditis elegans , Distúrbios Congênitos do Ciclo da Ureia/metabolismo , Distúrbios Congênitos do Ciclo da Ureia/patologia , Amiloide/metabolismo , Ornitina/metabolismo , Ureia
3.
ACS Omega ; 9(4): 4857-4869, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38313521

RESUMO

Insulin NPH is an intermediate-acting insulin. Its protracted action profile is due to the formation of microcrystalline suspensions when insulin is complexed with a basic peptide protamine, zinc ion, and phenolic ligands. Despite advancements in analytical techniques, the binding epitope and binding mode of the protamine in the insulin-protamine complex are still unknown. In this study, we used bioinformatics tools such as molecular docking and molecular dynamics (MD) simulations to compute the binding sites and energetics of the insulin-protamine complex. We have taken four naturally occurring protamine peptides that are independently docked with the insulin R6 hexamer and subjected them to 200 ns MD simulations to observe the dynamics of the complexes and estimate the binding energies. The arginine-rich protamine peptides were found to bind on the surface of the insulin hexamer through hydrogen bonding, hydrophobic, and electrostatic interactions well supported by the calculated negative binding energies. The overall structure of the insulin hexamer was retained upon binding, highlighting its dynamic stability in the complex. Furthermore, the residues at the termini of the protamine peptides in the complex were seen to be highly dynamic, which stabilize toward the end of the simulation.

4.
Phys Chem Chem Phys ; 26(4): 2995-3007, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38179672

RESUMO

An analytic theory based on the concept of "effective-fields" is proposed to explain the mechanism of polarization transfer from spin I = 1/2 to spin S = 1 in non-rotating (static) solids. Employing an isolated two-spin model system, the matching conditions responsible for polarization transfer in cross-polarization (CP) experiments are identified and described in terms of the single-transition operators. In contrast to other existing treatments, the polarization transfer among spins is quantified through analytic expressions highlighting the individual contributions emerging from all plausible CP matching conditions. The interplay between the CP matching conditions observed in experiments is outlined in both isotropic and anisotropic systems and verified through comparison between simulations based on analytic and exact numerical methods. The predictions emerging from the analytic theory are verified over a wide range of experimentally relevant parameters and could be beneficial in the optimization of the CP experiments.

5.
Discov Med ; 35(178): 673-696, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37811609

RESUMO

Pregnancy is often thought of as a time of happiness and anticipation, however, for some women, it can bring about significant emotional distress and feelings of vulnerability. The physiological changes that occur during pregnancy, including hormonal fluctuations and alterations to the immune and physical systems, can affect various parts of the body, including the central nervous system (CNS). As a result, existing conditions may be intensified or new ones, such as neurologic or psychiatric disorders, may arise, exposing women to increased risk of life-threatening conditions or suicide, in the worst-case scenarios. Given the impact of pregnancy on CNS diseases, it is crucial for healthcare providers and patients alike to be aware of these potential effects. By understanding how pregnancy may affect the CNS, clinicians can take appropriate steps to ensure that women receive the care and support they need to minimize any negative outcomes for both the mother and the baby. This paper aims to review the available evidence on the impact of pregnancy on CNS diseases, including mental health conditions, from both the clinical and biomolecular perspectives. By illuminating this crucial subject, this study fosters a delicate understanding within both patients and healthcare providers, thereby paving the way for enhanced outcomes for women throughout their pregnancy journey and beyond.


Assuntos
Doenças do Sistema Nervoso Central , Sistema Nervoso Central , Gravidez , Lactente , Humanos , Feminino , Imunidade
6.
Int J Mol Sci ; 24(17)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37686028

RESUMO

Lipids, characterized by their hydrophobic nature, encompass a wide range of molecules with distinct properties and functions [...].


Assuntos
Lipídeos , Humanos
7.
Biomedicines ; 11(4)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37189685

RESUMO

Lysosomal storage diseases are a group of rare and ultra-rare genetic disorders caused by defects in specific genes that result in the accumulation of toxic substances in the lysosome. This excess accumulation of such cellular materials stimulates the activation of immune and neurological cells, leading to neuroinflammation and neurodegeneration in the central and peripheral nervous systems. Examples of lysosomal storage diseases include Gaucher, Fabry, Tay-Sachs, Sandhoff, and Wolman diseases. These diseases are characterized by the accumulation of various substrates, such as glucosylceramide, globotriaosylceramide, ganglioside GM2, sphingomyelin, ceramide, and triglycerides, in the affected cells. The resulting pro-inflammatory environment leads to the generation of pro-inflammatory cytokines, chemokines, growth factors, and several components of complement cascades, which contribute to the progressive neurodegeneration seen in these diseases. In this study, we provide an overview of the genetic defects associated with lysosomal storage diseases and their impact on the induction of neuro-immune inflammation. By understanding the underlying mechanisms behind these diseases, we aim to provide new insights into potential biomarkers and therapeutic targets for monitoring and managing the severity of these diseases. In conclusion, lysosomal storage diseases present a complex challenge for patients and clinicians, but this study offers a comprehensive overview of the impact of these diseases on the central and peripheral nervous systems and provides a foundation for further research into potential treatments.

8.
Solid State Nucl Magn Reson ; 125: 101874, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37216831

RESUMO

The mutual orientation of nuclear spin interaction tensors provides critical information on the conformation and arrangement of molecules in chemicals, materials, and biological systems at an atomic level. Proton is a ubiquitous and important element in a variety of substances, and its NMR is highly sensitive due to their virtually 100% natural abundance and large gyromagnetic ratio. Nevertheless, the measurement of mutual orientation between the 1H CSA tensors has remained largely untouched in the past due to strong 1H-1H homonuclear interactions in a dense network of protons. In this study, we have developed a proton-detected 3D 1H CSA/1H CSA/1H CS correlation method that utilizes three techniques to manage homonuclear interactions, namely fast magic-angle spinning, windowless C-symmetry-based CSA recoupling (windowless-ROCSA), and a band-selective 1H-1H polarization transfer. The asymmetric 1H CSA/1H CSA correlated powder patterns produced by the C-symmetry-based methods are highly sensitive to the sign and asymmetry parameter of the 1H CSA, and the Euler angle ß as compared to the symmetric pattern obtained by the existing γ-encoded R-symmetry-based CSA/CSA correlation methods and allows a larger spectral area for data fitting. These features are beneficial for determining the mutual orientation between the nuclear spin interaction tensors with improved accuracy.


Assuntos
Imageamento por Ressonância Magnética , Prótons , Espectroscopia de Ressonância Magnética/métodos
9.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36430817

RESUMO

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2)-induced disease (COVID-19) and Gaucher disease (GD) exhibit upregulation of complement 5a (C5a) and its C5aR1 receptor, and excess synthesis of glycosphingolipids that lead to increased infiltration and activation of innate and adaptive immune cells, resulting in massive generation of pro-inflammatory cytokines, chemokines and growth factors. This C5a-C5aR1-glycosphingolipid pathway- induced pro-inflammatory environment causes the tissue damage in COVID-19 and GD. Strikingly, pharmaceutically targeting the C5a-C5aR1 axis or the glycosphingolipid synthesis pathway led to a reduction in glycosphingolipid synthesis and innate and adaptive immune inflammation, and protection from the tissue destruction in both COVID-19 and GD. These results reveal a common involvement of the complement and glycosphingolipid systems driving immune inflammation and tissue damage in COVID-19 and GD, respectively. It is therefore expected that combined targeting of the complement and sphingolipid pathways could ameliorate the tissue destruction, organ failure, and death in patients at high-risk of developing severe cases of COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , Doença de Gaucher , Humanos , Doença de Gaucher/tratamento farmacológico , Esfingolipídeos , SARS-CoV-2 , Proteínas do Sistema Complemento , Complemento C5a/metabolismo , Inflamação , Glicoesfingolipídeos
10.
Clin Transl Discov ; 2(2): e96, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35942236

RESUMO

Coronavirus disease 2019 (COVID-19) and the Gaucher disease (GD) exhibit lot of resemblances in induction of innate and adaptive immune inflammation that include the immune cells activation and the massive generation of pro-inflammatory cytokines, chemokines, and growth factors, which are all critical for propagation of the disease process and the multiple organ damage. However, majority of the GD patients have not revealed the expansion of severe form of the COVID-19. This study suggests that the pre-existing humoral immunity influence the devlopment of strong network of antibodies to different structural proteins of SARS-CoV2 in GD patients with COVID-19. Such antibodies and virus proteins interaction cause the comprehensive neutralization of SARS-CoV2 and provides protection from the development of severe form of COVID-19 in GD patients. This information could be helpful for better understanding of the disease mechanism as well as the development of additional potential therapy that could stop the growth of the severe symptoms and/or death in GD patients with COVID-19.

12.
Int J Mol Sci ; 23(3)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35163013

RESUMO

Parkinson's disease (PD) is the second-most common neurodegenerative disease in the world, affecting up to 10 million people. This disease mainly happens due to the loss of dopaminergic neurons accountable for memory and motor function. Partial glucocerebrosidase enzyme deficiency and the resultant excess accumulation of glycosphingolipids and alpha-synuclein (α-syn) aggregation have been linked to predominant risk factors that lead to neurodegeneration and memory and motor defects in PD, with known and unknown causes. An increasing body of evidence uncovers the role of several other lipids and their association with α-syn aggregation, which activates the innate and adaptive immune system and sparks brain inflammation in PD. Here, we review the emerging role of a number of lipids, i.e., triglyceride (TG), diglycerides (DG), glycerophosphoethanolamines (GPE), polyunsaturated fatty acids (PUFA), sphingolipids, gangliosides, glycerophospholipids (GPL), and cholesterols, and their connection with α-syn aggregation as well as the induction of innate and adaptive immune reactions that trigger neuroinflammation in PD.


Assuntos
Metabolismo dos Lipídeos , Doenças Neuroinflamatórias/metabolismo , Doença de Parkinson/imunologia , alfa-Sinucleína/química , Imunidade Adaptativa , Animais , Humanos , Imunidade Inata , Doenças Neuroinflamatórias/etiologia , Doença de Parkinson/complicações , Doença de Parkinson/metabolismo , Agregados Proteicos
13.
Int J Mol Sci ; 22(23)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34884512

RESUMO

Gaucher disease is a lysosomal storage disease, which happens due to mutations in GBA1/Gba1 that encodes the enzyme termed as lysosomal acid ß-glucosidase. The major function of this enzyme is to catalyze glucosylceramide (GC) into glucose and ceramide. The deficiency of this enzyme and resultant abnormal accumulation of GC cause altered function of several of the innate and adaptive immune cells. For example, augmented infiltration of T cells contributes to the increased production of pro-inflammatory cytokines, (e.g., IFNγ, TNFα, IL6, IL12p40, IL12p70, IL23, and IL17A/F). This leads to tissue damage in a genetic mouse model (Gba19V/-) of Gaucher disease. The cellular mechanism(s) by which increased tissue infiltration of T cells occurs in this disease is not fully understood. Here, we delineate role of the CXCR3 receptor and its exogenous C-X-C motif chemokine ligand 9 (CXCL9) in induction of increased tissue recruitment of CD4+ T and CD8+ T cells in Gaucher disease. Intracellular FACS staining of macrophages (Mϕs) and dendritic cells (DCs) from Gba19V/- mice showed elevated production of CXCL9. Purified CD4+ T cells and the CD8+ T cells from Gba19V/- mice showed increased expression of CXCR3. Ex vivo and in vivo chemotaxis experiments showed CXCL9 involvement in the recruitment of Gba19V/- T cells. Furthermore, antibody blockade of the CXCL9 receptor (CXCR3) on T cells caused marked reduction in CXCL9- mediated chemotaxis of T cells in Gba19V/- mice. These data implicate abnormalities of the CXCL9-CXCR3 axis leading to enhanced tissue recruitment of T cells in Gaucher disease. Such results provide a rationale for blockade of the CXCL9/CXCR3 axis as potential new therapeutic targets for the treatment of inflammation in Gaucher disease.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Quimiocina CXCL9/metabolismo , Modelos Animais de Doenças , Doença de Gaucher/imunologia , Glucosilceramidase/fisiologia , Inflamação/imunologia , Receptores CXCR3/metabolismo , Animais , Linfócitos T CD8-Positivos/patologia , Quimiocina CXCL9/genética , Doença de Gaucher/metabolismo , Doença de Gaucher/patologia , Inflamação/metabolismo , Inflamação/patologia , Ligantes , Macrófagos/imunologia , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores CXCR3/genética
14.
J Chem Phys ; 155(10): 104102, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34525823

RESUMO

A prescription based on bimodal Floquet theory is proposed to describe the nuances of phase-modulated supercycled decoupling experiments in solids. The frequency dependent interaction frames relevant to a particular supercycle are identified to facilitate faster convergence of perturbation corrections to the derived effective Hamiltonians. In contrast to silico-based methods, the proposed analytic method offers an attractive platform for faster optimization of experiments in solids. Additionally, the relevance of supercycling at ultrafast spinning conditions is also discussed.

15.
Indian J Nucl Med ; 36(2): 153-162, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34385786

RESUMO

Radiopharmaceutical preparations are the important pharmaceutical dosage forms used for the diagnosis and therapeutic purposes. Various pharmacopoeias are having methods for the quality control of these preparations in the form of monographs. Indian Pharmacopoeia (IP) also included these monographs in IP 2014 first time with the help of an experts' group on radiopharmaceutical, drawing expertise from elite stakeholder institutions and the core team of Indian Pharmacopoeia Commission. Since then, these standards are regularly updated through the IP addendum and bringing out new edition of IP. IP is a book of official methods as per Drugs and Cosmetic Act, 1940. These standards can be used in government laboratories, private laboratories, or academia in India and abroad. This review provides an overview of the journey of radiopharmaceuticals' standard setting in IP. A comprehensive comparative information of regulatory perspectives of radiopharmaceuticals in different jurisdictions such as the US, EU, and India is also presented.

16.
Front Neurol ; 12: 636139, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34239490

RESUMO

Parkinson's disease (PD) is a movement disorder attributed to the loss of dopaminergic (DA) neurons mainly in the substantia nigra pars compacta. Motor symptoms include resting tremor, rigidity, and bradykinesias, while non-motor symptoms include autonomic dysfunction, anxiety, and sleeping problems. Genetic mutations in a number of genes (e.g., LRRK2, GBA, SNCA, PARK2, PARK6, and PARK7) and the resultant abnormal activation of microglial cells are assumed to be the main reasons for the loss of DA neurons in PD with genetic causes. Additionally, immune cell infiltration and their participation in major histocompatibility complex I (MHCI) and/or MHCII-mediated processing and presentation of cytosolic or mitochondrial antigens activate the microglial cells and cause the massive generation of pro-inflammatory cytokines and chemokines, which are all critical for the propagation of brain inflammation and the neurodegeneration in PD with genetic and idiopathic causes. Despite knowing the involvement of several of such immune devices that trigger neuroinflammation and neurodegeneration in PD, the exact disease mechanism or the innovative biomarker that could detect disease severity in PD linked to LRRK2, GBA, SNCA, PARK2, PARK6, and PARK7 defects is largely unknown. The current review has explored data from genetics, immunology, and in vivo and ex vivo functional studies that demonstrate that certain genetic defects might contribute to microglial cell activation and massive generation of a number of pro-inflammatory cytokines and chemokines, which ultimately drive the brain inflammation and lead to neurodegeneration in PD. Understanding the detailed involvement of a variety of immune mediators, their source, and the target could provide a better understanding of the disease process. This information might be helpful in clinical diagnosis, monitoring of disease progression, and early identification of affected individuals.

17.
Int J Oncol ; 58(5)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33760154

RESUMO

Colorectal cancer (CRC) is the second most common malignancy causing cancer­related mortality globally. It is the third most common type of cancer detected worldwide. The recent concept of the human body supporting a diverse community of microbes has revealed the important role these microbes play synergistically in maintaining normal homeostasis. The balance between the microbiomes and epithelial cells of the human body is essential for normal physiology. Evidence from meta­genome analysis indicates that an imbalance in the microbiome is prominent in the guts of patients with CRC. Several studies have suggested that the gut microbiota can secrete metabolites [short­chain fatty acids (SCFAs), vitamins, polyphenols and polyamines] that modulate the susceptibility of the colon and rectum by altering inflammation and DNA damage. The state of microbiome imbalance (dysbiosis) has been reported in patients with CRC, with an increasing population of 'bad' microbes and a decrease in 'good' microbes. The 'good' microbes, also known as commensal microbes, produce butyrate; however, 'bad' microbes cause a pro­inflammatory state. The complex association between pathological microbial communities leading to cancer progression is not yet fully understood. An altered microbial metabolite profile plays a direct role in CRC metabolism. Furthermore, diet plays an essential role in the risk of gastrointestinal cancer development. High­fiber diets regulate the gut microbiome and reduce the risk of CRC development, and may be fruitful in the better management of therapeutics. In the present review, the current status of the microbiome in CRC development is discussed.12.


Assuntos
Bactérias/patogenicidade , Neoplasias Colorretais/microbiologia , Disbiose/complicações , Bactérias/classificação , Bactérias/metabolismo , Microbioma Gastrointestinal , Humanos
18.
ACS Omega ; 6(4): 3024-3036, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33553920

RESUMO

A supramolecular cucurbit[6]uril (CB[6])-enriched magnetic montmorillonite (CBCM) nanocomposite was prepared and characterized. CB[6] played a prominent role as a capping agent, helping in better distribution of the nanoparticles, and as a binder between nanoparticles. Montmorillonite provided structural stability and fortified ultrafast adsorption toward dyes. Its application in the removal of cationic dyes from wastewater was systematically assessed. Process parameters such as pH, initial dye concentration, dosage, temperature, and time were optimized. Kinetics and isotherms of the process were described using pseudo-second-order kinetics and the Langmuir isotherm, respectively. CBCM exhibited rapid dye removal capacity in short reaction times with q max of 199.20, 78.31, and 55.62 mg g-1 and K2 of 0.0281, 0.0.0823, and 0.0953 L mg-1 min-1 for crystal violet, methylene blue, and rhodamine B, respectively. Benefiting from the synergetic effects of montmorillonite surface hydrophobicity, abundant carbonyl groups of CB[6], and magnetic properties of copper ferrite, CBCM demonstrated outstanding dye removal capacity, negligible leaching at saturation, and high tolerance toward harsh conditions. This intrinsic nature is expedient in prolonged industrial operations. To demonstrate industrial viability, syringe filtration and continuous flow fixed-bed column operations were validated. The CBCM fixed-bed column demonstrated stable dye removal efficiency with 10-100 mg mL-1 dye at 10-50 mL min-1 flow rates. Utilizing the magnetic and catalytic activities of the copper ferrite nanoparticles, CBCM was recycled using a magnet, regenerated, and reused for several cycles. CB[6] remarkably improved the performance of the nanocomposite and made it suitable for different effluent treatment techniques. This may pave a sustainable way toward the efficient onsite treatment of effluent at the industrial scale.

19.
ACS Omega ; 6(2): 1030-1042, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33490762

RESUMO

The growth of high-quality single-crystal (SC) perovskite films is a great strategy for the fabrication of defect-free perovskite solar cells (PSCs) with photovoltaic parameters close to the theoretical limit, which resulted in high efficiency and superior stability of the device. Plenty of growth methods for perovskite SCs are available to achieve a maximum power conversion efficiency (PCE) surpassing 21% for SC-based PSCs. However, there is still a lot of room to further push the efficiency by considering new crystal growth techniques, interface engineering, passivation approaches, and additive engineering. In this review, we summarize the recent progress in the growth of SC-based perovskite films for the fabrication of high-efficiency and stable PSCs. We describe the impact of SC growth of perovskite films and their quality on the device performance and stability, compared with the commonly used polycrystalline perovskite films. In the last section, the challenges and potential of SCs in PSCs are also covered for future development.

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