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Individual differences in amygdala volumes predict changes in functional connectivity between subcortical and cognitive control networks throughout adolescence

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NEUROIMAGE 2022年 247卷 118852-118852页

作者： Taylor, Brittany K. Frenzel, Michaela R. Eastman, Jacob A. Embury, Christine M. Agcaoglu, Oktay Wang, Yu-Ping Stephen, Julia M. Calhoun, Vince D. Wilson, Tony W. Boys Town Natl Res Hosp Inst Human Neurosci Boys Town NE 68010 USA Creighton Univ Dept Pharmacol & Neurosci Omaha NE 68178 USA Univ Nebraska Dept Psychol Omaha NE 68182 USA Georgia State Univ Georgia Inst Technol Triinst Ctr Translat Res Neuroimaging & Data Sci Atlanta GA USA Emory Univ Atlanta GA 30322 USA Tulane Univ Dept Biomed Engn New Orleans LA 70118 USA Mind Res Network Albuquerque NM USA

Adolescence is a critical period of structural and functional neural maturation among regions serving the cognitive control of emotion. Evidence suggests that this process is guided by developmental changes in amygdala and striatum structure and shifts in functional connectivity between subcortical (SC) and cognitive control (CC) networks. Herein, we investigate the extent to which such developmental shifts in structure and function reciprocally predict one another over time. 179 youth (9-15 years-old) completed annual MRI scans for three years. Amygdala and striatum volumes and connectivity within and between SC and CC resting state networks were measured for each year. We tested for reciprocal predictability of within-person and between-person changes in structure and function using random-intercept cross-lagged panel models. Within-person shifts in amygdala volumes in a given year significantly and specifically predicted deviations in SC-CC connectivity in the following year, such that an increase in volume was associated with decreased SC-CC connectivity the following year. Deviations in connectivity did not predict changes in amygdala volumes over time. Conversely, broader group-level shifts in SC-CC connectivity were predictive of subsequent deviations in striatal volumes. We did not see any cross-predictability among amygdala or striatum volumes and within-network connectivity measures. Within-person shifts in amygdala structure year-to-year robustly predicted weaker SC-CC connectivity in subsequent years, whereas broader increases in SC-CC connectivity predicted smaller striatal volumes over time. These specific structure function relationships may contribute to the development of emotional control across adolescence.

关键词： Striatum Emotional control Development structure-function relationships Structural Equation Modeling (SEM) longitudinal

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structure-function relationships in conjugated materials containing tunable thieno[3,4-b]pyrazine units

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POLYMER BULLETIN 2012年第3期69卷 291-301页

作者： Mulholland, Michael E. Schwiderski, Ryan L. Rasmussen, Seth C. N Dakota State Univ NDSU Dept 2735 Dept Chem & Biochem Fargo ND 58108 USA

A series of 2,3-difunctionalized 5,7-bis(2-thienyl)thieno[3,4-b]pyrazines containing electron-donating and electron-withdrawing side chains are reported to evaluate the potential tuning effect of the side chains on the electronic properties of these common terthienyl building blocks. In order to further study the resulting effects of such side chains in polymeric materials, the dihexyloxy-functionalized terthienyl was copolymerized with fluorene and its electronic properties compared with a number of analogous materials.

关键词： Conjugated polymers Thieno[3,4-b]pyrazine structure-function relationships Electronic tuning

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Tyrosine 288 in the extracellular domain of the human P2X7 receptor is critical for receptor function revealed by structural modeling and site-directed mutagenesis

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PROTEINS-structure function AND BIOINFORMATICS 2022年第3期90卷 619-624页

作者： Caseley, Emily A. Muench, Stephen P. Jiang, Lin-Hua St James Univ Hosp Leeds Inst Rheumat & Musculoskeletal Med Leeds W Yorkshire England Univ Leeds Fac Biol Sci Sch Biomed Sci Leeds LS2 9JT W Yorkshire England

The P2X7 receptor (P2X7R) is a calcium-permeable cation channel activated by high concentrations of extracellular ATP. It plays a role in vital physiological processes, particularly in innate immunity, and is dysregulated in pathological conditions such as inflammatory diseases, neurodegenerative diseases, mood disorders, and cancers. Structural modeling of the human P2X7R (hP2X7R) based on the recently available structures of the rat P2X7 receptor (rP2XR) in conjunction with molecular docking predicts the orientation of tyrosine at position 288 (Y288) in the extracellular domain to face ATP. In this short communication, we combined site-directed mutagenesis and whole-cell patch-clamp recording to investigate the role of this residue in the hP2X7R function. Mutation of this extracellular residue to amino acids with different properties massively impaired current responses to both ATP and BzATP, suggesting that Y288 is important for normal receptor function. Such a finding facilitates development of an in-depth understanding of the molecular basis of hP2X7R structure-function relationships.

关键词： molecular docking patch-clamp recording site-directed mutagenesis structural modeling structure-function relationships

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Materiomically Designed Polymeric Vehicles for Nucleic Acids: Quo Vadis?

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ACS APPLIED BIO MATERIALS 2022年第6期5卷 2507-2535页

作者： Kumar, Ramya Colorado Sch Mines Dept Chem & Biol Engn Golden CO 80401 USA

Despite rapid advances in molecular biology, particularly in site-specific genome editing technologies, such as CRISPR/Cas9 and base editing, financial and logistical challenges hinder a broad population from accessing and benefiting from gene therapy. To improve the affordability and scalability of gene therapy, we need to deploy chemically defined, economical, and scalable materials, such as synthetic polymers. For polymers to deliver nucleic acids efficaciously to targeted cells, they must optimally combine design attributes, such as architecture, length, composition, spatial distribution of monomers, basicity, hydrophilic-hydrophobic phase balance, or protonation degree. Designing polymeric vectors for specific nucleic acid payloads is a multivariate optimization problem wherein even minuscule deviations from the optimum are poorly tolerated. To explore the multivariate polymer design space rapidly, efficiently, and fruitfully, we must integrate parallelized polymer synthesis, high-throughput biological screening, and statistical modeling. Although materiomics approaches promise to streamline polymeric vector development, several methodological ambiguities must be resolved. For instance, establishing a flexible polymer ontology that accommodates recent synthetic advances, enforcing uniform polymer characterization and data reporting standards, and implementing multiplexed in vitro and in vivo screening studies require considerable planning, coordination, and effort. This contribution will acquaint readers with the challenges associated with materiomics approaches to polymeric gene delivery and offers guidelines for overcoming these challenges. Here, we summarize recent developments in combinatorial polymer synthesis, high-throughput screening of polymeric vectors, omits-based approaches to polymer design, barcoding schemes for pooled in vitro and in vivo screening, and identify materiomics-inspired research directions that will realize the long-unfulfilled clini

关键词： nucleic acid delivery genome editing nonviral gene delivery polymers machine learning controlled radical polymerization high-throughput experimentation structure-function relationships

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Different phenotypic outcome due to site-specific phosphorylation in the cancer-associated NQO1 enzyme studied by phosphomimetic mutations

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ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS 2022年第0期729卷 000-000页

作者： Pacheco-Garcia, Juan Luis Anoz-Carbonell, Ernesto Loginov, Dmitry S. Vankova, Pavla Salido, Eduardo Man, Petr Medina, Milagros Palomino-Morales, Rogelio Pey, Angel L. Univ Granada Dept Quim Fis Ave Fuentenueva S-N Granada 18071 Spain Univ Zaragoza Fac Ciencias Dept Bioquim & Biol Mol & Cellular Inst Biocomp & Fis Sistemas Complejos BIFIGBsC CS Zaragoza 50009 Spain Acad Sci Czech Republ Inst Microbiol BioCeV Prumyslova 595 Vestec 25250 Czech Republic Acad Sci Czech Republ Inst Biotechnol BioCeV Prumyslova 595 Vestec 25250 Czech Republic Univ La Laguna Hosp Univ Canarias Ctr Rare Dis CIBERER Tenerife 38320 Spain Univ Granada Fac Sci Dept Biochem & Mol Biol 1 Granada Spain Univ Granada Biomed Res Ctr CIBM Granada Spain Univ Granada Dept Quim Fis Un Excelencia Quim Aplicada Biomed & Medioambiente Ave Fuentenueva S-N Granada 18071 Spain Univ Granada Inst Biotecnol Ave Fuentenueva S-N Granada 18071 Spain

Protein phosphorylation is a common phenomenon in human flavoproteins although the functional consequences of this site-specific modification are largely unknown. Here, we evaluated the effects of site-specific phosphorylation (using phosphomimetic mutations at sites S40, S82 and T128) on multiple functional aspects as well as in the structural stability of the antioxidant and disease-associated human flavoprotein NQO1 using biophysical and biochemical methods. In vitro biophysical studies revealed effects of phosphorylation at different sites such as decreased binding affinity for FAD and structural stability of its binding site (S82), conformational stability (S40 and S82) and reduced catalytic efficiency and functional cooperativity (T128). Local stability measurements by H/D exchange in different ligation states provided structural insight into these effects. Transfection of eukaryotic cells showed that phosphorylation at sites S40 and S82 may reduce steady-levels of NQO1 protein by enhanced proteasome-induced degradation. We show that site-specific phosphorylation of human NQO1 may cause pleiotropic and counterintuitive effects on this multifunctional protein with potential implications for its relationships with human disease. Our approach allows to establish relationships between site-specific phosphorylation, functional and structural stability effects in vitro and inside cells paving the way for more detailed analyses of phosphorylation at the flavoproteome scale.

关键词： Flavoprotein Phosphorylation structure-function relationships

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High spatiotemporal resolution transmission electron microscopy and diffraction: Progress from subnanosecond laser-induced structural dynamics to femtosecond quantum tomography

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NANO TODAY 2025年 61卷

作者： Aseyev, Sergei A. Mironov, Boris N. Poydashev, Denis G. Ryabov, Evgeny A. Miller, R. J. Dwayne Li, Zheng Zhang, Ming Ischenko, Anatoly A. RAS Inst Spect Fizicheskaya St 5 Moscow 108840 Russia Univ Toronto Dept Chem Toronto ON M5S 3H6 Canada Univ Toronto Dept Phys Toronto ON M5S 3H6 Canada Peking Univ State Key Lab Mesoscop Phys Beijing 100871 Peoples R China Peking Univ Collaborat Innovat Ctr Quantum Matter Sch Phys Beijing 100871 Peoples R China Shanxi Univ Collaborat Innovat Ctr Extreme Opt Taiyuan 030006 Shanxi Peoples R China Peking Univ Yangtze Delta Inst Optoelect Nantong 226010 Jiangsu Peoples R China MIREA Russian Technol Univ Inst Fine Chem Technol Dept Analyt Chem Vernadsky Ave 86 Moscow 119571 Russia

The use of short photoelectron pulses, pioneered in the 1980s, opened up the possibility of studying structural dynamics with high spatiotemporal resolution. The combination of nano-pico-femtosecond lasers with electron- based technology has become extremely fruitful for observing the behavior of atoms and molecules on their natural length and time scales. In imaging mode, this concept soon led to the creation of 4D transmission electron microscopy. In the electron diffraction mode, the achievement of ultrabright electron sources provided a unique opportunity to shoot molecular movies with atomic resolution. These sources are at their fundamental space charge limit with sufficient brightness to literally light up atomic motions. The high sensitivity of this approach, combined with low radiation damage, made it possible to atomically resolve reaction dynamics with nanograms of material. In contrast to the X-ray free electron lasers (XFELs), the development of ultrabright electron sources made it possible to conduct experiments on very thin films of promising materials in small-scale facilities in standard laboratories. The extension to quantum tomography has recently opened a new page in the study of matter using short electron bunches. Here we review the development of ultrafast transmission electron microscopy and diffraction techniques that enable detection of structural dynamics on the primary timescales.

关键词： Ultrafast transmission electron microscopy Simultaneous real space imaging Structural dynamics structure-function relationships Ultrafast laser-induced processes Transition state crossing Femtosecond quantum tomography

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Exopolysaccharide production by salt-tolerant bacteria: Recent advances, current challenges, and future prospects

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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES 2024年第Part2期264卷 130731页

作者： Gan, Longzhan Huang, Xin He, Zhicheng He, Tengxia Guizhou Univ Coll Life Sci Key Lab Plant Resource Conservat & Germplasm Innov Minist Educ Guiyang 550025 Guizhou Peoples R China

Natural biopolymers derived from exopolysaccharides (EPSs) are considered eco-friendly and sustainable alternatives to available traditional synthetic counterparts. Salt-tolerant bacteria inhabiting harsh ecological niches have evolved a number of unique adaptation strategies allowing them to maintain cellular integrity and assuring their long-term survival;among these, producing EPSs can be adopted as an effective strategy to thrive under high-salt conditions. A great diversity of EPSs from salt-tolerant bacteria have attracted widespread attention recently. Because of factors such as their unique structural, physicochemical, and functional characteristics, EPSs are commercially valuable for the global market and their application potential in various sectors is promising. However, large-scale production and industrial development of these biopolymers are hindered by their low yields and high costs. Consequently, the research progress and future prospects of salt-tolerant bacterial EPSs must be systematically reviewed to further promote their application and commercialization. In this review, the structure and properties of EPSs produced by a variety of salt-tolerant bacterial strains isolated from different sources are summarized. Further, feasible strategies for solving production bottlenecks are discussed, which provides a scientific basis and direct reference for more scientific and rational EPS development.

关键词： Biopolymer Exopolysaccharide Extremophile Salt-tolerant bacteria Biosynthesis structure-function relationships Production strategy

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Chitosan-Polyaniline (Bio)Polymer Hybrids by Two Pathways: A Tale of Two Biocomposites

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POLYMERS 2024年第18期16卷 2663页

作者： Anisimov, Yuriy A. Yang, Heng Kwon, Johnny Cree, Duncan E. Wilson, Lee D. McMaster Univ Dept Chem Engn Hamilton ON L8S 4M6 Canada Univ Saskatchewan Dept Chem 110 Sci Pl Saskatoon SK S7N 5C9 Canada McMaster Univ Dept Mech Engn Hamilton ON L8S 4L8 Canada

Previous research highlights the potential of polyaniline-based biocomposites as unique adsorbents for humidity sensors. This study examines several preparative routes for creating polyaniline (PANI) and chitosan (CHT) composites: Type 1-in situ polymerization of aniline with CHT;Type 2-molecular association in acidic aqueous media;and a control, Type 3-physical mixing of PANI and CHT powders (without solvent). The study aims to differentiate the bonding nature (covalent vs. noncovalent) within these composites, which posits that noncovalent composites should exhibit similar physicochemical properties regardless of the preparative route. The results indicate that Type 1 composites display features consistent with covalent and hydrogen bonding, which result in reduced water swelling versus Type 2 and 3 composites. These findings align with spectral and thermogravimetric data, suggesting more compact structure for Type 1 materials. Dye adsorption studies corroborate the unique properties for Type 1 composites, and H-1 NMR results confirm the role of covalent bonding for the in situ polymerized samples. The structural stability adopts the following trend: Type 1 (covalent and noncovalent) > Type 2 (possible trace covalent and mainly noncovalent) > Type 3 (noncovalent). Types 2 and 3 are anticipated to differ based on solvent-driven complex formation. This study provides greater understanding of structure-function relationships in PANI-biopolymer composites and highlights the role of CHT as a template that involves variable (non)covalent contributions with PANI, according to the mode of preparation. The formation of composites with tailored bonding modalities will contribute to the design of improved adsorbent materials for environmental remediation to versatile humidity sensor systems.

关键词： polyaniline-chitosan composites covalent bonding noncovalent interactions structure-function relationships

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Deciphering the interplay between pectin structural variability, intestinal bioavailability and gut microbiota metabolism: A review

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CARBOHYDRATE POLYMERS 2025年 360卷 123596页

作者： Zhao, Yuanyuan Aru, Violetta Wang, Dan Wang, Pan Qin, Peiyou Jiang, Qianqian Li, Zudi Engelsen, Soren Balling Zhao, Xiaoyan Beijing Acad Agr & Forestry Sci Inst Agrifood Proc & Nutr Beijing Key Lab Agr Prod Fruits & Vegetables Prese Key Lab Vegetable Postharvest ProcMinist Agr & Ru Beijing 100097 Peoples R China Univ Copenhagen Dept Food Sci DK-1958 Frederiksberg C Denmark

Pectins are parts of fruits, vegetables and other plant-based foods in the human daily diet. They are resilient to gastric digestion but undergo fermentation primarily in the large intestine, peaking in the cecum. The depolymerization of the pectins induced by the gut microbiota generally facilitates the subsequent fermentation of sugar monomers, during which SCFAs are primarily generated to exert multiple beneficial functions. Given structural heterogeneity of pectins and intricate process of microbial metabolism, it is crucial to elucidate how the multi-scale structure of pectins impacts their gut fermentation behavior. This review delves into distinct structural domains and fine structural characteristics of pectins, describes their degradation mechanism and bioavailability in the gastrointestinal tract, and provides an overview of the associated pectinolytic enzymes, gut microbiota community, and microbial metabolites. Moreover, recent advances are summarized in the relationships between gut fermentability and various structural parameters of pectins, including molecular size, esterification degree, monosaccharides composition and molecular conformation. Furthermore, how the structural complexity of pectins influences the interplay between saccharolytic metabolism and proteolytic metabolism during microbial fermentation is proposed. This work would help to unravel the "pectin structure-gut micro-biota-host health" interactions, thereby guiding the design of functional foods targeting specific microorganisms in future personalized diets.

关键词： Pectin Structural characteristics Fecal fermentation Gut microbiota Metabolic pathway structure-function relationships

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Eutectogels: Recent Advances and Emerging Biological Applications

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ADVANCED functionAL MATERIALS 2025年

作者： Hu, Yi Yang, Wenhui Zhan, Jiamian Pu, Chunyi Zhong, Linfang Hou, Honghao Southern Med Univ Affiliated Hosp 5 Guangzhou 510900 Guangdong Peoples R China Southern Med Univ Sch Basic Med Sci Guangdong Prov Key Lab Construct & Detect Tissue E Guangzhou 510515 Peoples R China

Eutectogels, a family of emerging materials, integrate the characteristics of deep eutectic solvents (DES) and gels, presenting unique application potential in biomedical engineering. However, the latest progress of eutectogels and their applications in the biomedical field remain to be summarized and refined. This review first introduces the composition of eutectogels and their unique properties generated by the interaction between DES and the gel matrix. Subsequently, the classifications and advantages of eutectogels are comprehensively discussed according to their cross-linked preparation methods, including physical, chemical, and multiple cross-linked. By analyzing the properties of eutectogels, such as mechanical performance, thermal properties, conductivity, injectability, and their structure-function relationships, the application potential of eutectogels is overviewed. Then, the eutectogel's application prospects in biomedical engineering are elaborated in detail, including their application in drug delivery to improve drug stability and precise control release, enhancing curative effects and reducing side effects. Also, the functional utilization in tissue engineering, biosensing, bioadhesives, and related biomedical domains are comprehensively explored. Finally, existing challenges and prospective research directions of eutectogels are delineated.

关键词： bioadhesives biomedical engineering biosensing eutectogels structure-function relationships

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