Hasil untuk "Chemical technology"

Sunghwan Kim, Jie Chen, Tiejun Cheng et al.

PubChem (https://pubchem.ncbi.nlm.nih.gov) is a large and highly-integrated public chemical database resource at NIH. In the past two years, significant updates were made to PubChem. With additions from over 130 new sources, PubChem contains >1000 data sources, 119 million compounds, 322 million substances and 295 million bioactivities. New interfaces, such as the consolidated literature panel and the patent knowledge panel, were developed. The consolidated literature panel combines all references about a compound into a single list, allowing users to easily find, sort, and export all relevant articles for a chemical in one place. The patent knowledge panels for a given query chemical or gene display chemicals, genes, and diseases co-mentioned with the query in patent documents, helping users to explore relationships between co-occurring entities within patent documents. PubChemRDF was expanded to include the co-occurrence data underlying the literature knowledge panel, enabling users to exploit semantic web technologies to explore entity relationships based on the co-occurrences in the scientific literature. The usability and accessibility of information on chemicals with non-discrete structures (e.g. biologics, minerals, polymers, UVCBs and glycans) were greatly improved with dedicated web pages that provide a comprehensive view of all available information in PubChem for these chemicals.

R. Crane, T. Scott

L. Gold, Deborah Ayers, Jennifer Bertino et al.

BACKGROUND The interrogation of proteomes ("proteomics") in a highly multiplexed and efficient manner remains a coveted and challenging goal in biology and medicine. METHODOLOGY/PRINCIPAL FINDINGS We present a new aptamer-based proteomic technology for biomarker discovery capable of simultaneously measuring thousands of proteins from small sample volumes (15 µL of serum or plasma). Our current assay measures 813 proteins with low limits of detection (1 pM median), 7 logs of overall dynamic range (~100 fM-1 µM), and 5% median coefficient of variation. This technology is enabled by a new generation of aptamers that contain chemically modified nucleotides, which greatly expand the physicochemical diversity of the large randomized nucleic acid libraries from which the aptamers are selected. Proteins in complex matrices such as plasma are measured with a process that transforms a signature of protein concentrations into a corresponding signature of DNA aptamer concentrations, which is quantified on a DNA microarray. Our assay takes advantage of the dual nature of aptamers as both folded protein-binding entities with defined shapes and unique nucleotide sequences recognizable by specific hybridization probes. To demonstrate the utility of our proteomics biomarker discovery technology, we applied it to a clinical study of chronic kidney disease (CKD). We identified two well known CKD biomarkers as well as an additional 58 potential CKD biomarkers. These results demonstrate the potential utility of our technology to rapidly discover unique protein signatures characteristic of various disease states. CONCLUSIONS/SIGNIFICANCE We describe a versatile and powerful tool that allows large-scale comparison of proteome profiles among discrete populations. This unbiased and highly multiplexed search engine will enable the discovery of novel biomarkers in a manner that is unencumbered by our incomplete knowledge of biology, thereby helping to advance the next generation of evidence-based medicine.

Linghong Zhang, C. Xu, P. Champagne

G. Brodeur, E. Yau, K. Badal et al.

Overcoming the recalcitrance (resistance of plant cell walls to deconstruction) of lignocellulosic biomass is a key step in the production of fuels and chemicals. The recalcitrance is due to the highly crystalline structure of cellulose which is embedded in a matrix of polymers-lignin and hemicellulose. The main goal of pretreatment is to overcome this recalcitrance, to separate the cellulose from the matrix polymers, and to make it more accessible for enzymatic hydrolysis. Reports have shown that pretreatment can improve sugar yields to higher than 90% theoretical yield for biomass such as wood, grasses, and corn. This paper reviews different leading pretreatment technologies along with their latest developments and highlights their advantages and disadvantages with respect to subsequent hydrolysis and fermentation. The effects of different technologies on the components of biomass (cellulose, hemicellulose, and lignin) are also reviewed with a focus on how the treatment greatly enhances enzymatic cellulose digestibility.

M. Aresta

L. Lavis, Ronald T. Raines

C. McDonagh, C. Burke, B. MacCraith

A. Kinloch

J. Kurreck

P. Vesborg, T. Jaramillo

The energy infrastructure for fossil fuels is well-established, accounting for approximately 87% of the 16 TW of power consumed globally. For renewable and sustainable energy conversion technologies to play a relevant role at the terrestrial scale, they must be able to scale to the TW level of deployment. This would place a significant demand on the current and future supply of raw materials (chemical elements) used by those technologies. Oftentimes, the average crustal abundance of a chemical element is cited as a measure of its scalability, however another important metric for scalability is the existence (of lack thereof) of mineable ores with a high concentration of the targeted element. This paper aims to provide an overview of the availability of all elements. This is accomplished via a compilation of data for global primary production rates for each element, as a measure of availability at the present time. This work also addresses the potential future availability based on current and possible future primary sources.

Robbie A Clark, Michael P. Shaver

The societal importance of plastics contrasts with the carelessness with which they are disposed. Their superlative properties lead to economic and environmental efficiency, but the linearity of plastics puts the climate, human health, and global ecosystems at risk. Recycling is fundamental to transitioning this linear model into a more sustainable, circular economy. Among recycling technologies, chemical depolymerization offers a route to virgin quality recycled plastics, especially when valorizing complex waste streams poorly served by mechanical methods. However, chemical depolymerization exists in a complex and interlinked system of end-of-life fates, with the complementarity of each approach key to environmental, economic, and societal sustainability. This review explores the recent progress made into the depolymerization of five commercial polymers: poly(ethylene terephthalate), polycarbonates, polyamides, aliphatic polyesters, and polyurethanes. Attention is paid not only to the catalytic technologies used to enhance depolymerization efficiencies but also to the interrelationship with other recycling technologies and to the systemic constraints imposed by a global economy. Novel polymers, designed for chemical depolymerization, are also concisely reviewed in terms of their underlying chemistry and potential for integration with current plastic systems.

M. Peters, B. Köhler, W. Kuckshinrichs et al.

F. Yavari, N. Koratkar

Charles M. Cai, Taiying Zhang, R. Kumar et al.

Mehmet Isik, H. Sardón, D. Mecerreyes

Due to its abundance and a wide range of beneficial physical and chemical properties, cellulose has become very popular in order to produce materials for various applications. This review summarizes the recent advances in the development of new cellulose materials and technologies using ionic liquids. Dissolution of cellulose in ionic liquids has been used to develop new processing technologies, cellulose functionalization methods and new cellulose materials including blends, composites, fibers and ion gels.

Meiyu Shao, Xiaoqing Zhang, Jiamei Sun et al.

ABSTRACT Saikosaponin b1 (Ssb1), a natural oleanane‐type triterpenoid saponin, exhibits antifibrosis activity by inhibiting the activation of hepatic stellate cells (HSCs), but the specific underlying molecular mechanisms are unknown. Here, it is found that Ssb1 could directly bind with the signal transducer and activator of transcription 3 (STAT3) and effectively inhibit the activation of HSCs. Proteomic techniques and molecular simulation revealed that Ssb1 is mainly bound to the S319 residues of STAT3 in the coiled‐coil domain. Further studies indicated that Ssb1 binding with STAT3 inhibited its transcriptional activity, and regulated glioma‐associated oncogene‐1 (Gli1) expression in the Hedgehog signaling pathway. Besides, Ssb1 binding blocked interaction between STAT3 and Gli1, which promoted degradation of Gli1 protein by suppressor of fused homolog (SUFU) and the ubiquitin‐proteasome system. The loss function of Gli1 led to decreased expression of Bcl2 and promoted the apoptosis of activated HSCs. Moreover, STAT3 ablation abolished the Ssb1‐mediated antifibrotic effects. These findings show that STAT3 plays a vital role in Ssb1 treatment of liver fibrosis, and Ssb1 as a STAT3 inhibitor might be a promising therapeutic candidate for the treatment of hepatic fibrosis.

Alice Marinangeli, Pinar Cakir Hatir, Mustafa Baris Yagci et al.

In this work, we report the development of a highly sensitive optical sensor for the detection of cardiac troponin I (cTnI), a key biomarker for early-stage myocardial infarction diagnosis. The sensor combines castor oil-derived biomimetic receptors, called GreenNanoMIPs and prepared via the molecular imprinting technology using as a template an epitope of cTnI (i.e., the NR10 peptide), with a portable multimode plastic optical fiber surface plasmon resonance (POF-SPR) transducer. For sensing, gold SPR chips were functionalized with GreenNanoMIPs as proven by refractive index changes and confirmed by means of XPS. Binding experiments demonstrated the cTnI_nanoMIP-SPR sensor’s ability to detect both the NR10 peptide epitope and the full-length cTnI protein within minutes (t = 10 min), with high sensitivity and selectivity in buffer and serum matrices. The cTnI_nanoMIP-SPR showed an LOD of 3.53 × 10⁻¹⁵ M, with a linearity range of 1 pM–100 pM, outperforming previously reported sensor platforms and making it a promising tool for early-stage myocardial infarction detection.

Salvatore Forgia

Scopo del presente studio è stato quello di valutare l’attività anti-Listeria di un estratto etanolico di propoli (EEP) proveniente dalla Tunisia, sia in vitro che in situ in ricotta zuccherata mediante challenge test, indagando nel contempo se un’eventuale attività antimicrobica sia in grado di prolungarne la shelf-life senza alterarne le caratteristiche sensoriali. L'estratto etanolico, ottenuto dalla propoli grezza raccolta da alveari di Apis mellifera, veniva preparato in un rapporto di 20% di propoli e 80% di solvente (Etanolo 80%) (p/v). L'attività antibatterica dell'EEP veniva analizzata in vitro con il metodo di Disk Diffusion Assay (1 g/ml; 250 mg/ml; 150 mg/ml) valutando, inoltre, la minima concentrazione battericida (MBC) e inibente (MIC) da 25 a 0,0125 mg/ml contro n. 6 ceppi di Listeria monocyotogens (ATCC 19111; 19112; 7644 + tre ceppi della linee guida EURL per prodotti lattiero caseari 12MOB098LM, 12MOB096LM e 12MOB079LM). La valutazione in situ è stata condotta su n. 2 tipologie di ricotta zuccherata: una industriale vaccina (RZIV) e la seconda semi-artigianale di pecora (RZSP) del commercio, entrambe addizionate in laboratorio con 40% di saccarosio. Ogni tipologia di ricotta zuccherata veniva suddivisa in 2 aliquote: dalla prima, destinata al challenge test, venivano ottenute più sub-aliquote, contaminate sperimentalmente con un mix dei n. 3 ceppi di L. monocytogenes (12MOB098LM, 12MOB096LM e 12MOB079LM) e trattate con concentrazioni differenti di EEP (0, 0,1 e 1%). La seconda aliquota, suddivisa a sua volta in più sub-aliquote, veniva addizionata con 0 e 0,1 % di EEP per la RZIV e 0 e 1% di EEP per la RZSP, e analizzati ad intervalli regolari per la valutazione sensoriale e per la shelf-life analizzando i seguenti parametri microbiologici: Carica batterica totale (CBT,), Enterobacteriaceae, Pseudomonas spp. e batteri lattici. I risultati del Disk Diffusion Assay mostravano una buona attività antibatterica dell’EEP contro tutti i ceppi di L. monocytogenes per tutte le concentrazioni saggiate. La MIC ottenuta per L. monocytogenes variava da 0,25 per i ceppi ATCC a 0,625 mg/ml per i tre ceppi EURL, mentre, la MBC era la stessa della MIC per due dei tre ceppi EURL e 1,25 mg/ml per tutti gli altri ceppi. Per quanto riguarda il challenge test, dopo 14 giorni nella RZIV veniva osservata una differenza significativa nella crescita di L. monocytogenes tra il Δ del campione controllo (+6,10 log CFU/g) e del campione trattato con 1% EEP (+ 3,84 log CFU/g). Nella RZSP, veniva osservata una minore crescita del patogeno, con un Δ del campione di controllo (+ 2,78 log CFU/g) e dei campioni trattati con l'1% di EEP (+ 1,04 log CFU/g). Relativamente all’influenza sulla shelf-life, solo nei campioni RZSP trattati con l’1% di EEP si osservano differenze sia per la CBT (- 1,25 log UFC/g) che per i batteri lattici (- 0,81 log UFC/g); Infine, nei campioni trattati con l’1% si osservava una diminuzione nel tempo dell’impatto sensoriale. I risultati del presente studio hanno messo in evidenza come l’EEP possegga una discreta attività anti L. monocytogenes, mostrando risultati promettenti anche nella ricotta zuccherata trattata con l’1% di EEP. Gli estratti di popoli potrebbero quindi rappresentare una valida alternativa naturale ai comuni additivi e trattamenti utilizzati a livello industriale per la gestione del rischio di tale patogeno.

Arben Ristemi

The process of decentralization in the Republic of North Macedonia is an important step towards strengthening local government and distributing political, economic, and social resources across the country. The decentralization period began in 2005 with amendments to the Constitution of the Republic of Macedonia and other legal provisions that created a framework for redistributing powers, resources, and responsibilities from the central government to local governments. The goal of the decentralization process is to ensure greater autonomy for local authorities, enable more efficient resource management, and increase the effectiveness of public services. However, as practice shows, this process also brings numerous challenges, such as a lack of financial resources, insufficiently trained personnel, and inadequate coordination between different levels of government. This paper aims to examine the decentralization process in the Republic of North Macedonia, with a particular focus on its impact on local government, the problems and challenges faced by municipalities, and the changes in legal and institutional frameworks.