Destruction of Chitosan and Its Complexes with Cobalt(II) and Copper(II) Tetrasulphophthalocyanines

Chitosan is a naturally occurring polysaccharide derived from chitin with a wide range of uses. Phthalocyanines are macroheterocyclic compounds that have a number of useful properties such as coloring and catalytic and antioxidant activity. Phthalocyanines are able to immobilize on chitosan, forming complexes with new useful properties. In this work, we evaluated the ability of phthalocyanines to increase the thermal stability of chitosan. Chitosan (CS) forms complexes with copper(II)-(CuPc) and cobalt(II)-(CoPc) tetrasulphophthalocyanines. The processes of destruction of chitosan (CS) and its complexes with sulphophthalocyanines CuPc and CoPc in oxidizing and inert atmospheres have been studied. It was established that, regardless of the atmosphere composition, the first chemical reactions taking place in the studied systems are elimination reactions. The latter ones in the case of chitosan and complex CS-CuPc lead to the formation of spatially crosslinked polymer structures, and it causes the release of CuPc from the polymer complex. It was found that in the case of CS-CoPc elimination reactions did not lead to the formation of crosslinked polymer structures but caused the destruction of the pyranose rings with a partial release of CoPc. Metallophthalocyanines showed antioxidant properties in the composition of complexes with chitosan, increasing the temperature of the beginning of glycosidic bond cleavage reaction by 30–35 °C in comparison with the similar characteristics for chitosan.

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Flavonoids as Potential Therapeutic Agents for the Management of Diabetic Neuropathy

Current Pharmaceutical Design ◽

10.2174/1381612826666200826164322 ◽

2020 ◽

Vol 26 (42) ◽

pp. 5468-5487 ◽

Cited By ~ 1

Author(s):

Ankita Sood ◽

Bimlesh Kumar ◽

Sachin Kumar Singh ◽

Pankaj Prashar ◽

Anamika Gautam ◽

...

Keyword(s):

Neuropathic Pain ◽

Diabetic Neuropathy ◽

Glucose Utilization ◽

Antioxidant Properties ◽

Therapeutic Agents ◽

Secondary Complications ◽

Naturally Occurring ◽

Glycation End Products ◽

Treatment Of Diabetes ◽

Pharmaceutical Industries

Flavonoids are secondary metabolites that are widely distributed in plants. These phenolic compounds are classified into various subgroups based on their structures: flavones, flavonols, isoflavones, flavanones, and anthocyanins. They are known to perform various pharmacological actions like antioxidant, anti-inflammatory, anticancer, antimicrobial, antidiabetic and antiallergic, etc. Diabetes is a chronic progressive metabolic disorder that affects several biochemical pathways and leads to secondary complications such as neuropathy, retinopathy, nephropathy, and cardiomyopathy. Among them, the management of diabetic neuropathy is one of the major challenges for physicians as well as the pharmaceutical industries. Naturally occurring flavonoids are extensively used for the treatment of diabetes and its related complications due to their antioxidant properties. Moreover, flavonoids inhibit various pathways that are involved in the progression of diabetic neuropathy like the reduction of oxidative stress, decrease in glycogenolysis, increase glucose utilization, decrease in the formation of advanced glycation end products, and inhibition of the α-glucosidase enzyme. This review entails current updates on the therapeutic perspectives of flavonoids in the treatment of neuropathic pain. This manuscript explains the pathological aspects of neuropathic pain, the chemistry of flavonoids, and their application in amelioration of neuropathic pain through preclinical studies either alone or in combination with other therapeutic agents.

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Naturally occurring genotypes of the human immunodeficiency virus type 1 long terminal repeat display a wide range of basal and Tat-induced transcriptional activities.

Journal of Virology ◽

10.1128/jvi.68.5.3163-3174.1994 ◽

1994 ◽

Vol 68 (5) ◽

pp. 3163-3174 ◽

Cited By ~ 45

Author(s):

N L Michael ◽

L D'Arcy ◽

P K Ehrenberg ◽

R R Redfield

Keyword(s):

Human Immunodeficiency Virus ◽

Long Terminal Repeat ◽

Human Immunodeficiency Virus Type ◽

Virus Type ◽

Terminal Repeat ◽

Naturally Occurring ◽

Wide Range ◽

Immunodeficiency Virus

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Modes of Interaction in Naturally Occurring Medical Encounters With General Practitioners: The “One in a Million” Study

Qualitative Health Research ◽

10.1177/1049732321993790 ◽

2021 ◽

pp. 104973232199379

Author(s):

Olaug S. Lian ◽

Sarah Nettleton ◽

Åge Wifstad ◽

Christopher Dowrick

Keyword(s):

General Practitioners ◽

Narrative Analysis ◽

Mode Competition ◽

General Applicability ◽

Naturally Occurring ◽

Wide Range ◽

The One ◽

Narrative Mode ◽

Modes Of Interaction

In this article, we qualitatively explore the manner and style in which medical encounters between patients and general practitioners (GPs) are mutually conducted, as exhibited in situ in 10 consultations sourced from the One in a Million: Primary Care Consultations Archive in England. Our main objectives are to identify interactional modes, to develop a classification of these modes, and to uncover how modes emerge and shift both within and between consultations. Deploying an interactional perspective and a thematic and narrative analysis of consultation transcripts, we identified five distinctive interactional modes: question and answer (Q&A) mode, lecture mode, probabilistic mode, competition mode, and narrative mode. Most modes are GP-led. Mode shifts within consultations generally map on to the chronology of the medical encounter. Patient-led narrative modes are initiated by patients themselves, which demonstrates agency. Our classification of modes derives from complete naturally occurring consultations, covering a wide range of symptoms, and may have general applicability.

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The Potential Effects of Phytoestrogens: The Role in Neuroprotection

Molecules ◽

10.3390/molecules26102954 ◽

2021 ◽

Vol 26 (10) ◽

pp. 2954

Author(s):

Justyna Gorzkiewicz ◽

Grzegorz Bartosz ◽

Izabela Sadowska-Bartosz

Keyword(s):

Neuroprotective Effect ◽

Antioxidant Properties ◽

Estrogen Therapy ◽

Neuroprotective Effects ◽

Potential Health ◽

Naturally Occurring ◽

Epigenetic Effects ◽

Estrogen Synthesis ◽

Health Promoting ◽

The Brain

Phytoestrogens are naturally occurring non-steroidal phenolic plant compounds. Their structure is similar to 17-β-estradiol, the main female sex hormone. This review offers a concise summary of the current literature on several potential health benefits of phytoestrogens, mainly their neuroprotective effect. Phytoestrogens lower the risk of menopausal symptoms and osteoporosis, as well as cardiovascular disease. They also reduce the risk of brain disease. The effects of phytoestrogens and their derivatives on cancer are mainly due to the inhibition of estrogen synthesis and metabolism, leading to antiangiogenic, antimetastatic, and epigenetic effects. The brain controls the secretion of estrogen (hypothalamus-pituitary-gonads axis). However, it has not been unequivocally established whether estrogen therapy has a neuroprotective effect on brain function. The neuroprotective effects of phytoestrogens seem to be related to both their antioxidant properties and interaction with the estrogen receptor. The possible effects of phytoestrogens on the thyroid cause some concern; nevertheless, generally, no serious side effects have been reported, and these compounds can be recommended as health-promoting food components or supplements.

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Isobornylchalcones as Scaffold for the Synthesis of Diarylpyrazolines with Antioxidant Activity

Molecules ◽

10.3390/molecules26123579 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3579

Author(s):

Svetlana A. Popova ◽

Evgenia V. Pavlova ◽

Oksana G. Shevchenko ◽

Irina Yu. Chukicheva ◽

Aleksandr V. Kutchin

Keyword(s):

Antioxidant Activity ◽

Antioxidant Properties ◽

Biological Properties ◽

High Reactivity ◽

Biologically Active ◽

Brain Lipids ◽

Wide Range ◽

Privileged Structure ◽

Vitro Model

The pyrazoline ring is defined as a “privileged structure” in medicinal chemistry. A variety of pharmacological properties of pyrazolines is associated with the nature and position of various substituents, which is especially evident in diarylpyrazolines. Compounds with a chalcone fragment show a wide range of biological properties as well as high reactivity which is primarily due to the presence of an α, β-unsaturated carbonyl system. At the same time, bicyclic monoterpenoids deserve special attention as a source of a key structural block or as one of the pharmacophore components of biologically active molecules. A series of new diarylpyrazoline derivatives based on isobornylchalcones with different substitutes (MeO, Hal, NO2, N(Me)2) was synthesized. Antioxidant properties of the obtained compounds were comparatively evaluated using in vitro model Fe2+/ascorbate-initiated lipid peroxidation in the substrate containing brain lipids of laboratory mice. It was demonstrated that the combination of the electron-donating group in the para-position of ring B and OH-group in the ring A in the structure of chalcone fragment provides significant antioxidant activity of synthesized diarylpyrazoline derivatives.

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Regulation of Cytochrome c Oxidase by Natural Compounds Resveratrol, (–)-Epicatechin, and Betaine

Cells ◽

10.3390/cells10061346 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1346

Author(s):

Icksoo Lee

Keyword(s):

Cytochrome C ◽

Cytochrome C Oxidase ◽

Model Systems ◽

Health Improvement ◽

Published Data ◽

Mitochondrial Electron Transport Chain ◽

Naturally Occurring ◽

Transport Chain ◽

Wide Range ◽

Experimental Model Systems

Numerous naturally occurring molecules have been studied for their beneficial health effects. Many compounds have received considerable attention for their potential medical uses. Among them, several substances have been found to improve mitochondrial function. This review focuses on resveratrol, (–)-epicatechin, and betaine and summarizes the published data pertaining to their effects on cytochrome c oxidase (COX) which is the terminal enzyme of the mitochondrial electron transport chain and is considered to play an important role in the regulation of mitochondrial respiration. In a variety of experimental model systems, these compounds have been shown to improve mitochondrial biogenesis in addition to increased COX amount and/or its enzymatic activity. Given that they are inexpensive, safe in a wide range of concentrations, and effectively improve mitochondrial and COX function, these compounds could be attractive enough for possible therapeutic or health improvement strategies.

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Strategies and methodologies for the construction of spiro-fused γ-lactams: an update

Organic Chemistry Frontiers ◽

10.1039/d0qo01564d ◽

2021 ◽

Author(s):

Américo José dos Santos Alves ◽

Nuno Guerreiro Alves Alves ◽

Maria I.L. Soares ◽

Teresa M. V. D. Pinho e Melo

Keyword(s):

Naturally Occurring ◽

Wide Range ◽

Spirocyclic Compounds

Spiro-γ-lactams (spiropyrrolinin-2-ones) are a class of spirocyclic compounds that are present in a wide range of synthetic bioactive and naturally occurring molecules. The increasing attention to spirocyclic lactams in drug...

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Development and characterization of electrospun curcumin-loaded antimicrobial nanofibrous membranes

Textile Research Journal ◽

10.1177/0040517520925514 ◽

2020 ◽

pp. 004051752092551

Author(s):

Javeed A Awan ◽

Saif Ur Rehman ◽

Muhammad Kashif Bangash ◽

Fiaz Hussain ◽

Jean-Noël Jaubert

Keyword(s):

Biological Activities ◽

Research Work ◽

Medical Applications ◽

Electrospinning Technique ◽

Naturally Occurring ◽

Wide Range ◽

Nanofibrous Membranes ◽

Antimicrobial Barrier ◽

Anti Hiv

Curcumin is a naturally occurring hydrophobic polyphenol compound. It exhibits a wide range of biological activities such as antibacterial, anti-inflammatory, anti-carcinogenic, antifungal, anti-HIV, and antimicrobial activity. In this research work, antimicrobial curcumin nanofibrous membranes are produce by an electrospinning technique using the Eudragit RS 100 (C19H34ClNO6) polymer solution enriched with curcumin. The morphology and chemistry of the membrane are analyzed using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Kirby Bauer disk diffusion tests are carried out to examine the antibacterial effectiveness of the membrane. Experimental results show that the nanofibers produced are of uniform thickness morphology and curcumin is successfully incorporated into the nanofibrous mat, while no chemical bonding was observed between curcumin and the polymer. The antimicrobial curcumin nanofibrous membranes can be effectively applied as antimicrobial barrier in a wide variety of medical applications such as wound healing, scaffolds, and tissue engineering.

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Breeding Strategies to Improve Miscanthus as a Sustainable Source of Biomass for Bioenergy and Biorenewable Products

Agronomy ◽

10.3390/agronomy9110673 ◽

2019 ◽

Vol 9 (11) ◽

pp. 673 ◽

Cited By ~ 7

Author(s):

John Clifton-Brown ◽

Kai-Uwe Schwarz ◽

Danny Awty-Carroll ◽

Antonella Iurato ◽

Heike Meyer ◽

...

Keyword(s):

Significant Contribution ◽

Perennial Grass ◽

Time Frame ◽

Eastern Asia ◽

Germplasm Collections ◽

Naturally Occurring ◽

Wide Range ◽

Yield Quality ◽

Short Time ◽

Commercial Expansion

Miscanthus, a C4 perennial grass native to Eastern Asia, is being bred to provide biomass for bioenergy and biorenewable products. Commercial expansion with the clonal hybrid M. × giganteus is limited by low multiplication rates, high establishment costs and drought sensitivity. These limitations can be overcome by breeding more resilient Miscanthus hybrids propagated by seed. Naturally occurring fast growing indigenous Miscanthus species are found in diverse environments across Eastern Asia. The natural diversity provides for plant breeders, the genetic resources to improve yield, quality, and resilience for a wide range of climates and adverse abiotic stresses. The challenge for Miscanthus breeding is to harness the diversity through selections of outstanding wild types, parents, and progenies over a short time frame to deploy hybrids that make a significant contribution to a world less dependent on fossil resources. Here are described the strategies taken by the Miscanthus breeding programme at Aberystwyth, UK and its partners. The programme built up one of the largest Miscanthus germplasm collections outside Asia. We describe the initial strategies to exploit the available genetic diversity to develop varieties. We illustrate the success of combining diverse Miscanthus germplasm and the selection criteria applied across different environments to identify promising hybrids and to develop these into commercial varieties. We discuss the potential for molecular selections to streamline the breeding process.

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