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1.
In recent years, the medicinal potential of marine organisms has attracted increasing attention. This is due to their immense diversity and adaptation to unique ecological niches that has led to vast physiological and biochemical diversification. Among these organisms, marine calcifiers are an abundant source of novel proteins and chemical entities that can be used for drug discovery. Studies of the skeletal organic matrix proteins of marine calcifiers have focused on biomedical applications such as the identification of growth inducing proteins that can be used for bone regeneration, for example, 2/4 bone morphogenic proteins (BMP). Although a few reports on the functions of proteins derived from marine calcifiers can be found in the literature, marine calcifiers themselves remain an untapped source of proteins for the development of innovative pharmaceuticals. Following an overview of the current knowledge of skeletal organic matrix proteins from marine calcifiers, this review will focus on various aspects of marine skeletal protein research including sources, biosynthesis, structures, and possible strategies for chemical or physical modification. Special attention will be given to potential medical applications and recent discoveries of skeletal proteins and polysaccharides with biologically appealing characteristics. In addition, I will introduce an effective protocol for sample preparation and protein purification that includes isolation technology for biopolymers (of both soluble and insoluble organic matrices) from coralline algae. These algae are a widespread but poorly studied group of shallow marine calcifiers that have great potential for marine drug discovery.  相似文献   

2.
Dopachrome, the initial pigment leading to enzymatic browning, was produced in the presence of crude enzyme preparation from homogenized tissues or sliced disks of raw potatoes. The formation of dopachrome seemed to depend upon 3,4-dihydroxyphenylalanine (DOPA) oxidation catalyzed by polyphenol oxidase. The pH of the aqueous medium influenced the production of this pigment. As the pH of the aqueous medium became lower, dopachrome formation and black melanin production were slower. To inhibit the production of dopachrome in sliced disks of raw potatoes, a much-higher concentration of sodium sulfite (Na2SO3) was required than that bleaching dopachrome which had been already formed.  相似文献   

3.
As one of the most important interfaces in cellular systems, biological membranes have essential functions in many activities such as cellular protection and signaling. Beyond their direct functions, they also serve as scaffolds to support the association of proteins involved in structural support, adhesion, and transport. Unfortunately, biological processes sometimes malfunction and require therapeutic intervention. For those processes which occur within or upon membranes, it is oftentimes difficult to study the mechanism in a biologically relevant, membranous environment. Therefore, the identification of direct therapeutic targets is challenging. In order to overcome this barrier, engineering strategies offer a new approach to interrogate biological activities at membrane interfaces by analyzing them through the principles of the interfacial sciences. Since membranes are complex biological interfaces, the development of simplified model systems which mimic important properties of membranes can enable fundamental characterization of interaction parameters for such processes. We have selected the hepatitis C virus (HCV) as a model viral pathogen to demonstrate how model membrane platforms can aid antiviral drug discovery and development. Responsible for generating the genomic diversity that makes treating HCV infection so difficult, viral replication represents an ideal step in the virus life cycle for therapeutic intervention. To target HCV genome replication, the interaction of viral proteins with model membrane platforms has served as a useful strategy for target identification and characterization. In this review article, we demonstrate how engineering approaches have led to the discovery of a new functional activity encoded within the HCV nonstructural 5A protein. Specifically, its N-terminal amphipathic, α-helix (AH) can rupture lipid vesicles in a size-dependent manner. While this activity has a number of exciting biotechnology and biomedical applications, arguably the most promising one is in antiviral medicine. Based on the similarities between lipid vesicles and the lipid envelopes of virus particles, experimental findings from model membrane platforms led to the prediction that a range of medically important viruses might be susceptible to rupturing treatment with synthetic AH peptide. This hypothesis was tested and validated by molecular virology studies. Broad-spectrum antiviral activity of the AH peptide has been identified against HCV, HIV, herpes simplex virus, and dengue virus, and many more deadly pathogens. As a result, the AH peptide is the first in class of broad-spectrum, lipid envelope-rupturing antiviral agents, and has entered the drug pipeline. In summary, engineering strategies break down complex biological systems into simplified biomimetic models that recapitulate the most important parameters. This approach is particularly advantageous for membrane-associated biological processes because model membrane platforms provide more direct characterization of target interactions than is possible with other methods. Consequently, model membrane platforms hold great promise for solving important biomedical problems and speeding up the translation of biological knowledge into clinical applications.  相似文献   

4.
A tire is a composite of rubber and reinforcing materials. Polymeric materials used as reinforcing components are usually synthetic yarns. These synthetic yarns have high tenacity, they are made of continuous multifilaments. The yarns are converted in the cord form to provide desired mechanical, thermal and adhesion properties by a series of conversion processes. Besides of multifilament synthetic cords, there are some specific areas in which single ply monofilament cords have been utilized as a reinforcing element. In this study, new cord structures have been developed by using monofilament yarns and by imitating multifilament cords. New cord structures exhibited some very interesting cord properties compared to both single ply monofilament cord and multifilament cords. Monofilament yarns having diameter between 0.23 and 0.50 mm have been twisted together from 3 to 6 plies based on mixed Taguchi model to form cords. Nylon 6.6 and Polyester monofilament yarns have been selected because of common application of their multifilament counterpart yarns in tire carcass and capply. The twisted monofilament cords have been adhesive treated to produce cords ready to adhere rubber. The mechanical properties, thermal stability, adhesion with rubber, fatigue properties under dynamic conditions, retention of properties after curing and microscopic analysis of the cords have been analyzed. The cords have been found to possess some benefits for tire carcass, breaker, belt and belt protective layer applications with their superior fatigue performance, cut resistance, stiffness, ligth weigth etc.  相似文献   

5.
6.
Specialty materials such as essential oils, pharmaceuticals, colorants, dyes, cosmetics and biocides are obtained from plants. Many species of medicinal and aromatic plants (MAPs) are cultivated for such industrial uses, but most are still wild collected. The need for renewable sources of industrial products as well as the need to protect plant biodiversity creates an opportunity for farmers to produce such crops. The production of plants as raw material for fine chemicals is different than cultivation of ornamental or food crops. This review attempts to give an overview of the use of MAPs in various industries, as well as trends in the various markets involved. Economic and regulatory issues relevant for such uses of MAP material are also discussed, with a focus on the situation in the European Union. The aim is to provide information to potential producers to help identify interesting MAPs for cultivation.  相似文献   

7.
A straightforward approach was proposed to modify cotton fabric for oil/water separation based on musselinspired reaction. The poly(DMA-Octadecyl acrylate) was designed to contain key chemical constituents present in mussel adhesive proteins by free radical polymerization of dopamine hydrochloride and octadecyl acrylate, which strongly adsorbed to fabric substrates, providing a special surface for fabric. The chemical structure, surface topography, and surface wettability of the fabric were characterized. The results showed that as-prepared cotton fabric displayed a high CA of >150° when dripped water droplets were on the modified fabric surface, and the oil contact angle (OCA) was close to 0°, it had excellent potential to be used in practical applications and has created a new method of fabric modification for oil/water separation.  相似文献   

8.
Tetrahydropyrans are structural motifs that are abundantly present in a range of biologically important marine natural products. As such, significant efforts have been paid to the development of efficient and versatile methods for the synthesis of tetrahydropyran derivatives. Neopeltolide, a potent antiproliferative marine natural product, has been an attractive target compound for synthetic chemists because of its complex structure comprised of a 14-membered macrolactone embedded with a tetrahydropyran ring, and twenty total and formal syntheses of this natural product have been reported so far. This review summarizes the total and formal syntheses of neopeltolide and its analogues, highlighting the synthetic strategies exploited for constructing the tetrahydropyran ring.  相似文献   

9.
Yang Y  Koo S  Lin CS  Neu B 《Biointerphases》2010,5(3):FA19-FA23
Adhesion of red blood cells (RBCs) to endothelial cells (ECs) is usually insignificant but an enhanced adhesion has been observed in various diseases associated with vascular complications. This abnormal adhesion under pathological conditions such as sickle cell disease has been correlated with increased levels of various plasma proteins but the detailed underlying mechanism(s) remains unclear. Usually it is assumed that the proadhesive effects of plasma proteins originate from ligand interactions cross-linking receptors on adjacent cells, but explicit results detailing binding sites or receptors for some proteins (e.g., fibrinogen) on either RBC or EC surfaces that would support this model are missing. In this study, the authors tested whether there is an alternative mechanism. Their results demonstrate that dextran 2 MDa promotes the adhesion of normal RBCs to thrombin-activated ECs and that this effect becomes more pronounced with increasing thrombin concentration or with prolonged thrombin incubation time. It is concluded that depletion interaction originating from nonadsorbing macromolecules (i.e., dextran) can modulate the adhesion of red blood cells to thrombin-activated EC. This study thereby suggests macromolecular depletion as an alternative mechanism for the adhesion-promoting effects of nonadsorbing plasma proteins. These findings should not only aid in getting a better understanding of diseases associated with vascular complications but should also have many potential applications in biomedical or biotechnological areas that require the control of cell-cell or cell surface interactions.  相似文献   

10.
Protein fibre wastes from animal hairs, feathers and insect secreted filaments can be aptly utilized by converting them into ultra-fine particles. Particles from animal protein fibres present large surface-to-weight ratio and significantly enhanced surface reactivity, that have opened up novel applications in both textile and non-textile fields. This review article summarizes the state-of-the-art routes to fabricate ultrafine particles from animal protein fibres, including direct route of mechanical milling of fibres and indirect route from fibre proteins. Ongoing research trends in novel applications of protein fibre particles in various fields, such as biomedical science, environmental protection and composite structures are presented.  相似文献   

11.
For both, environmental and medical applications, the quantification of bacterial adhesion is of major importance to understand and support the development of new materials. For marine applications, the demand is driven by the quest for improved fouling-release coatings. To determine the attachment strength of bacteria to coatings, a microfluidic adhesion assay has been developed which allows probing at which critical wall shear stress bacteria are removed from the surface. Besides the experimental setup and the optimization of the assay, we measured adhesion of the marine bacterium Cobetia marina on a series of differently terminated self-assembled monolayers. The results showed that the adhesion strength of C. marina changes with surface chemistry. The difference in critical shear stress needed to remove bacteria can vary by more than one order of magnitude if a hydrophobic material is compared to an inert chemistry such as polyethylene glycol.  相似文献   

12.
Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease with a prevalence rate of up to 1% and is significantly considered a common worldwide public health concern. Commercially, several traditional formulations are available to treat RA to some extent. However, these synthetic compounds exert toxicity and considerable side effects even at lower therapeutic concentrations. Considering the above-mentioned critiques, research is underway around the world in finding and exploiting potential alternatives. For instance, marine-derived biologically active compounds have gained much interest and are thus being extensively utilized to confront the confines of in practice counterparts, which have become ineffective for 21st-century medical settings. The utilization of naturally available bioactive compounds and their derivatives can minimize these synthetic compounds’ problems to treat RA. Several marine-derived compounds exhibit anti-inflammatory and antioxidant properties and can be effectively used for therapeutic purposes against RA. The results of several studies ensured that the extraction of biologically active compounds from marine sources could provide a new and safe source for drug development against RA. Finally, current challenges, gaps, and future perspectives have been included in this review.  相似文献   

13.
Surface characterization of materials has been considered critical in the development of biomaterials, as many unfavorable responses from the body occur at the interface between a material and the body component. The contact angle measurement is one means to characterize the surface properties and to correlate them to the biocompatibility of materials. In this paper, surface characteristics of silk fibroin/S-carboxymethyl kerateine, representative fibrous proteins, were investigated by contact angle measurements and ESCA. The biocompatibility of the blends was evaluated based on minimal interfacial free energy concept, and compared with other potential biomaterials. It was also hypothesized that the enhanced surface polarity of the blends was generated from the conformational transition of proteins. This approach to evaluate the biocompatibility of materials based on surface characteristics may find wide utility in many biomedical applications.  相似文献   

14.
Nowadays, the use of marine by-products as precursor materials has gained great interest in the extraction and production of chemical compounds with suitable properties and possible pharmaceutical applications. The present paper presents the development of a new immediate release tablet containing calcium lactate obtained from Black Sea mussel shells. Compared with other calcium salts, calcium lactate has good solubility and bioavailability. In the pharmaceutical preparations, calcium lactate was extensively utilized as a calcium source for preventing and treating calcium deficiencies. The physical and chemical characteristics of synthesized calcium lactate were evaluated using Fourier Transform Infrared Spectroscopy, X-ray diffraction analysis and thermal analysis. Further, the various pharmacotechnical properties of the calcium lactate obtained from mussel shells were determined in comparison with an industrial used direct compressible Calcium lactate DC (PURACAL®). The obtained results suggest that mussel shell by-products are suitable for the development of chemical compounds with potential applications in the pharmaceutical domain.  相似文献   

15.
Produced via electrospinning, polyurethane (PU) scaffolds have always attracted the interest of medical applications due of their unique properties such as good adhesion, biocompatibility and excellent mechanical strength. However, the poor hydrophilicity and hemocompatibility of PU presented a problem during PU’s application in the manufacturing of biomedical materials. We hypothesized that the incorporation of polyethylene glycol (PEG) and phosphatidylcholine (PC) into electrospinning solution of PU could improve the cell affinity and hemocompatibility. This research focused on fabricating hybrid PU-PEG and PU-PC random/aligned scaffolds through electrospinning technique and comparing their properties as a potential biocompatible scaffold for vascular tissue engineering. PC was doped into a PU solution in order to prepare an electrospun scaffold through the electrospinning technology while crosslinked electrospun PUPEG hybrid scaffolds were fabricated by photoinduced polymerization. The contact angle dramatically decreased from 122.3±0.8° to 39.1±0.8° with doping of PC in electrospinning solution while it decreased from 122.3±0.8° to 41.6±0.8° with doping of PEG. Furthermore, the mechanical properties of PU scaffolds were altered significantly by the addition of PC. The hemolysis and cytocompatibility assays demonstrated that these composite scaffolds could potentially be used as a smalldiameter vascular graft.  相似文献   

16.
Biopolymers are very favorable materials produced by living organisms, with interesting properties such as biodegradability, renewability, and biocompatibility. Biopolymers have been recently considered to compete with fossil-based polymeric materials, which rase several environmental concerns. Biobased plastics are receiving growing interest for many applications including electronics, medical devices, food packaging, and energy. Biopolymers can be produced from biological sources such as plants, animals, agricultural wastes, and microbes. Studies suggest that microalgae and cyanobacteria are two of the promising sources of polyhydroxyalkanoates (PHAs), cellulose, carbohydrates (particularly starch), and proteins, as the major components of microalgae (and of certain cyanobacteria) for producing bioplastics. This review aims to summarize the potential of microalgal PHAs, polysaccharides, and proteins for bioplastic production. The findings of this review give insight into current knowledge and future direction in microalgal-based bioplastic production considering a circular economy approach. The current review is divided into three main topics, namely (i) the analysis of the main types and properties of bioplastic monomers, blends, and composites; (ii) the cultivation process to optimize the microalgae growth and accumulation of important biobased compounds to produce bioplastics; and (iii) a critical analysis of the future perspectives on the field.  相似文献   

17.
Marine resources are today a renewable source of various compounds, such as polysaccharides, that are used in the pharmaceutical, medical, cosmetic, and food fields. In recent years, considerable attention has been focused on carrageenan-based biomaterials due to their multifunctional qualities, including biodegradability, biocompatibility, and non-toxicity, in addition to bioactive attributes, such as their antiviral, antibacterial, antihyperlipidemic, anticoagulant, antioxidant, antitumor, and immunomodulating properties. They have been applied in pharmaceutical formulations as both their bioactive and physicochemical properties make them suitable biomaterials for drug delivery, and recently for the development of tissue engineering. This article provides a review of recent research on the various types of carrageenan-based biomedical and pharmaceutical applications.  相似文献   

18.
Theranostics is an integrated nanosystem that combines therapeutics with diagnostics in attempt to develop new personalized treatments with enhanced therapeutic efficacy and safety. As a promising therapeutic paradigm with cutting-edge technologies, theranostic agents are able to simultaneously deliver therapeutic drugs and diagnostic imaging agents and also monitor the response to therapy. Polymeric nanosystems have been intensively explored for biomedical applications to diagnose and treat various cancers. In recent years, glycol chitosan-based nanoagents have been developed as dual-purpose materials for simultaneous diagnosis and therapy. They have shown great potential in cancer therapies, such as chemotherapeutics and nucleic acid and photodynamic therapies. In this review, we summarize the recent progress and potential applications of glycol chitosan-based fluorescent theranostic nanoagents for cancer treatments and discuss their possible underlying mechanisms.  相似文献   

19.
Bhatnagar I  Kim SK 《Marine drugs》2010,8(10):2702-2720
Cancer is considered as one of the deadliest diseases in the medical field. Apart from the preventive therapies, it is important to find a curative measure which holds no loopholes and acts accurately and precisely to curb cancer. Over the past few decades, there have been advances in this field and there are many antitumor compounds available on the market, which are of natural as well as synthetic origin. Marine chemotherapy is well recognized nowadays and profound development has been achieved by researchers to deal with different molecular pathways of tumors. However, the marine environment has been less explored for the production of safe and novel antitumor compounds. The reason is a number of shortfalls in this field. Though ample reviews cover the importance and applications of various anticancerous compounds from marine natural products, in the present review, we have tried to bring the current status of antitumor research based on marine inhibitors of cancer signaling pathways. In addition, focus has been placed on the shortfalls and probable strategies in the arena of marine antitumor drug discovery.  相似文献   

20.
One of the challenges to the management of severe asthma is the poor therapeutic response to treatment with glucocorticosteroids. Compounds derived from marine sources have received increasing interest in recent years due to their prominent biologically active properties for biomedical applications, as well as their sustainability and safety for drug development. Based on the pathobiological features associated with glucocorticoid resistance in severe asthma, many studies have already described many glucocorticoid resistance mechanisms as potential therapeutic targets. On the other hand, in the last decade, many studies described the potentially anti-inflammatory effects of marine-derived biologically active compounds. Analyzing the underlying anti-inflammatory mechanisms of action for these marine-derived biologically active compounds, we observed some of the targeted pathogenic molecular mechanisms similar to those described in glucocorticoid (GC) resistant asthma. This article gathers the marine-derived compounds targeting pathogenic molecular mechanism involved in GC resistant asthma and provides a basis for the development of effective marine-derived drugs.  相似文献   

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