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Abstract: Over-prescription of medicines leads to some crucial health issues like resistance, non-specificity, etc. Therefore, a human consumes various natural foods, therapeutics, and nutritional supplements to combat this problem. Various therapeutic properties of secondary metabolites, such as anticancer, anti-inflammatory, and antibacterial properties, are important in drug discovery and medicinal application. These natural products have replaced synthetic materials, resulting in a great deal of sustainability, rational use, and preservation of biodiversity. This review described the potential therapeutic applications of secondary plant metabolites found in Himalayan Indian plants. The database contains 45 plants to treat various diseases, such as cancer, inflammation, and microbial infections. Besides authorized ITIS names, it includes Hindi names, family names, and active constituents. The most important information about the molecules can be found in the hyperlinks for the active constituents. It includes structures (two-dimensional and threedimensional), names and identifiers, chemical and physical properties, spectral information, biochemistry, literature and patents. The review also references various phytochemicals responsible for preventing COVID-19. Despite several challenges in manufacturing natural products, researchers may conduct research to produce successful medicines with few side effects.

A high incidence of bone defects and the limitation of autologous bone grafting require 3D scaffolds for bone repair. Compared with synthetic materials, natural edible materials possess outstanding advantages in terms of biocompatibility, bioactivities and low manufacturing cost for bone tissue engineering. In this work, attracted by the natural porous/fabric structure, good biocompatibility and bioactivities of the lotus root, the lotus root-based scaffolds were fabricated and investigated their potential to serve as natural porous bone tissue engineering scaffolds. The results indicated that the lotus root-based scaffolds possess suitable natural microstructure, excellent biocompatibility and promising functions, such as antioxidant capacity and angiogenesis promotion. Remarkably, lotus root scaffolds showed encouraging possibility of bone tissue engineering while the mineralized lotus root could further improve the bone regeneration in vivo. All the results demonstrated the bone regeneration potential of lotus root-based scaffolds equipped with suitable natural architecture, excellent biocompatibility, specific bioactivities and low manufacturing cost.

Background: Nanotechnology is a tool being used intensely in the area of drug delivery systems in the biomedical field. Electrospraying is one of the nanotechnological methods, which is growing due to its importance in the development of nanoparticles comprising bioactive compounds. It is helpful in improving the efficacy, reducing side effects of active drug elements, and is useful in targeted drug delivery. When compared to other conventional methods like nanoprecipitation, emulsion diffusion, and double emulsification, electrospraying offers better advantages to produce micro/nanoparticles due to its simplicity, cost-effectiveness, and single-step process. Objective: The aim of this paper is to highlight the use of electrosprayed nanoparticles for biomedical applications. Methods: We conducted a literature review on the usage of natural and synthetic materials to produce nanoparticles, which can be used as a drug delivery system for medical purposes. Results: We summarized a possible key role of electrosprayed nanoparticles in different therapeutic applications (tissue regeneration, cancer). Conclusion: The modest literature production denotes that further investigation is needed to assess and validate the promising role of drug-loaded nanoparticles through the electrospraying process as noninvasive materials in the biomedical field.

Myocardial infarction (MI) is one of the common cardiovascular diseases that occurs with a blockage in one or more of the coronary arteries to lead to the damage of the myocardium, resulting in a life-threatening condition. To repair the damaged myocardium in MI, researchers are looking forwards to new ways to postpone the progression of myocardial injury. Cardiac patches, the scaffolds layered on the heart surface, can provide mechanical support for the infarction site and improve cardiac function by delivering various bioactive factors or cells, showing considerable curative effect in the treatment of MI. Biomaterials with certain biocompatibility and mechanical properties have received widespread attention for the application in cardiac patches. In this review, we focus on the recent progress on these biomaterials-based cardiac patches, which could be categorized into two types according to the sources of materials including (ⅰ) natural materials and (ⅱ) synthetic materials. The major advantages and current challenges of each type are discussed and a brief perspective on the future research directions is presented.

Composites or composite materials are engineered materials that consist of two or more constituent materials with wide discrepancies in their physical, chemical, and mechanical properties. The characteristic properties of these composite are as a result of the individual properties of their constituent parts and their respective volume fractions and arrangements in the material system. Depending on the intended application, composites can be designed to satisfy specific geometrical, structural, mechanical, chemical, and sometimes aesthetic requirements. Areas of application of these synthetic materials includes construction such as in buildings and bridges, automotive industry such as in car bodies, aeronautic, naval (e.g., ships and boats), and in the biomedical fields. Although metallic, polymeric and ceramic biomaterials have been in use for medical treatments such as tissue repairs and replacements for decades, composites are just coming to light. Therefore, the main purpose of this paper is to introduce composite materials and discuss their current and potential use in the biomedical field.

Background Synthetic materials, increasingly used for indoor and outdoor surfaces including homes and playgrounds, may contain toxic chemicals. Infants have a higher potential of exposure to chemicals in these materials, which may pose a risk to their health. Objective To understand potential risks related to outdoor surface coverings, based on a review of the literature and regulations, and to assess levels of hazardous chemicals in surface coverings in Israel. Methods We reviewed the literature and regulations on artificial turf. We tested 46 samples of surfaces for trace metals in synthetic playground surfaces; trace metals, phthalates, and di(2-ethylhexyl) terephthalate (DEHT) in synthetic grass, and phthalates, DEHT and formaldehyde in laminate flooring. Results Twelve studies reporting high levels of polycyclic aromatic hydrocarbons (PAH), and varying levels of trace metals in synthetic playground surfaces were identified, as well as five international regulations on lead with maximum acceptable concentrations in the range 40-500 mg/kg. Surface tests showed that 20 out of 30 samples of synthetic playground surfaces exceeded relevant standards for trace metals, of which five had cadmium levels ≥30 mg/kg and four had chromium levels ≥510 mg/kg. In synthetic grass, three out of eight samples exceeded relevant standards, with lead levels ≥1200 mg/kg. In Laminate flooring (n = 8) formaldehyde levels were in the range of 0.7-1.2 mg/m2 formaldehyde, and five samples contained ~5% DEHT. Significance The literature on chemicals in surfaces is limited, but indicates some exceedance of regulatory limits. Trace metals in synthetic playground surfaces and synthetic grass, not regulated in Israel, exceeded relevant international standards in 72% of samples. Laminate flooring, regulated for formaldehyde, did not exceed the 3.5 mg/m2 standard, but contained DEHT, a replacement for ortho-substituted phthalates. The results of this preliminary study show that flooring surfaces may be a source of children's exposure to toxic chemicals. Impact statement Synthetic surfaces are increasingly being used in, for example, children's playgrounds and sports fields. Exceedances of regulatory limits from other jurisdictions, of heavy metal levels in most outdoor surfaces sampled in Israel indicates the potential for children's exposure. Domestic regulations should be implemented to reduce the risk to children from exposure to these surfaces.

The rich structures and hierarchical organizations in nature provide many sources of inspiration for advanced material designs. We wish to recapitulate properties such as high mechanical strength, colour-changing ability, autonomous healing and antimicrobial efficacy in next-generation synthetic materials. Common in nature are non-covalent interactions such as hydrogen bonding, ionic interactions and hydrophobic effects, which are all useful motifs in tailor-made materials. Among these are biobased components, which are ubiquitously conceptualized in the space of recently developed bioinspired and biomimetic materials. In this regard, sustainable organic polymer chemistry enables us to tune the properties and functions of such materials that are essential for daily life. In this Review, we discuss recent progress in bioinspired and biomimetic polymers and provide insights into biobased materials through the evolution of chemical approaches, including networking/crosslinking, dynamic interactions and self-assembly. We focus on advances in biobased materials; namely polymeric mimics of resilin and spider silk, mechanically and optically adaptive materials, self-healing elastomers and hydrogels, and antimicrobial polymers. This Review describes bioinspired biomimetic polymers that recapitulate macro-scale to atomic-scale features of naturally occurring materials. Particular attention is paid to biobased concepts, with an eye to having renewable supplies of self-healing, stimuli-responsive and/or antimicrobial materials.

Background Considering the complexity of lung structures and the difficulty of thoracoscopic surgery, simulation-based training is of paramount importance for junior surgeons. Here, we aim to design a high-fidelity lung model through utilizing the three-dimensional (3D) printing technology combined with synthetic materials to mimic the real human lung. Methods The 3D printed lung model was manufactured based on the computed tomography images of a randomly selected male patient. Synthetic materials were used for the construction of lung parenchyma, blood vessels, and bronchi. Then, the model was assessed in terms of its visual, tactile, and operational features by participants (the senior surgeons, junior surgeons, and medical students), who were asked to complete the specially designed survey-questionnaires. Results A 3D printed model of the right lung made of synthetic materials was successfully fabricated. Thirty subjects participated in our study (10 senior surgeons, 10 junior surgeons, and 10 medical students). The average visual evaluation scores for senior surgeons, junior surgeons, and medical students were 3.97 ± 0.61, 4.56 ± 0.58, 4.76 ± 0.49, respectively. The average tactile evaluation scores were 3.40 ± 0.50, 4.13 ± 0.68, 4.00 ± 0.64, respectively. The average operation evaluation scores were 3.33 ± 0.83, 3.93 ± 0.66, 4.03 ± 0.66, respectively. Significant lower scores were obtained in the group of the senior surgeons compared with the other two groups. Conclusion A high level of fidelity was exhibited in our 3D printed lung model and it could be applied as a promising simulator for the surgical training in the future.

The bamboo marrow of raffia hookeri (BMRH) has been characterized for a potential alternative to synthetic materials and possible new applications. This work consisted in investigating the physical...

Mantis shrimps use their dactyl club to strike multiple high-velocity impacts against stiff and hard surfaces. To sustain the loads and dissipate energy, their club has evolved a complex multiscale organization segmented in an impact surface, an impact region, and a periodic region. Composed essentially of nanoparticles, mineralized chitin microfibers, and proteins, each region exhibits microstructural specificities linked to energy dissipating mechanisms. Fabricating synthetic materials that exploit similar organizations and mechanisms could lead to the development of lightweight impact-resistant strategies for a multitude of applications. To this aim, the microstructure and properties of the natural dactyl club and its key toughening mechanisms are reviewed, as well as current and potential fabrication approaches. Challenges and limitations of those approaches are discussed to hopefully help guide future research on bioinspired impact-resistant materials. National Research Foundation (NRF) The authors acknowledge financial support from the National Research Foundation, Singapore, with the Fellowship NRFF12-2020-0006

The combination of biological and synthetic materials has great potential to generate new types of biosensors. Toward this goal, recent advances in artificial cell development have demonstrated the capacity to detect a variety of analytes and environmental changes by encapsulating genetically encoded sensors within bilayer membranes, expanding the contexts within which biologically based sensing can operate. This chassis not only acts as a container for cell-free sensors, but can also play an active role in artificial cell sensing by serving as an additional gate mediating the transfer of environmental information. Here, we focus on recent progress toward stimuli-responsive artificial cells and discuss strategies for membrane functionalization in order to expand cell-free biosensing capabilities and applications.

Molecular self-assembly is pervasive in the formation of living and synthetic materials. Knowledge gained from research into the principles of molecular self-assembly drives innovation in the biological, chemical, and materials sciences. Self-assembly processes span a wide range of temporal and spatial domains and are often unintuitive and complex. Studying such complex processes requires an arsenal of analytical and computational tools. Within this arsenal, the transmission electron microscope stands out for its unique ability to visualize and quantify self-assembly structures and processes. This review describes the contribution that the transmission electron microscope has made to the field of molecular self-assembly. An emphasis is placed on which TEM methods are applicable to different structures and processes and how TEM can be used in combination with other experimental or computational methods. Finally, we provide an outlook on the current challenges to, and opportunities for, increasing the impact that the transmission electron microscope can have on molecular self-assembly.

Shifting from excessive use of uncontrollable synthetic materials to environmentally friendly natural materials, especially from Agricultural waste such as banana stem fibres, offers an attractive ...

This paper presents the results of the application of new unique techniques based on plasma nanotechnology in metallurgy and materials science. In recent years, a team of authors have developed the solutions for extraordinary problems arising in the conditions of metallurgical enterprises related to the production of synthetic materials and control of manufactured products, namely, the methods for the production of various structural materials and optimization of methods for their non-destructive testing by atomic emission spectral analysis (AESA). The paper points out some aspects of ongoing research, in particular, an innovative technique that allows obtaining ultrapure samples of white corundum by plasma melting of alumina in a reactor. This method also allows obtaining ultrapure aluminum at the output, which can be used for the purposes of hydrogen energy. In the course of the research, the criteria for thermal protection, temperature conditions and optimal parameters of the plasmatron were determined. In order to carry out the studies of metals and alloys by AESA method, a new global analytical method was developed, which made it possible to take into account the influence of various important parameters, including third elements, background plasma radiation, etc. This method has been preliminary tested on emission spectrometers made in Russia and can significantly reduce the error in the determination of low concentrations of elements. In addition to the consideration of these parameters, the method makes it possible to perform high-precision calibration of atomic emission spectrometers of the same type (produced in series), using not a set of several tens of approved standard samples, but only two standard samples. For each area, patent applications were formed and filed.

AIM: This study aimed to summarize the accumulated experience and compare available materials for the plasty of dura mater (DM) defects. The growing number of patients with craniocerebral traumas and an increasing amount of neurological surgeries for tumor processes and congenital malformations resulted in an increased amount of DM defects and associated complications. Despite the development of high-efficiency medical products, the percentage of postsurgical CSF leakage remains high and reaches 32% in case the defect is in infratentorial locations. Suitable substitute materials should be developed for the repair of dural defects because of complications such as pseudomeningocele, postsurgical inflammatory processes, CSF leakage, implant rejection, and cicatrical adhesion. In this article, basic materials, including auto- and allografts, biological substances, and synthetic materials, for the repair of dural defects were reviewed. Their positive and negative properties depending on the kind and location of lesions and on the type of material used were discussed. The main characteristics to be fulfilled by an ideal dura mater substitute were analyzed. Composite materials were considered a promising trend in modern bioengineering. CONCLUSION: An ideal material for the repair of DM defects should have the following properties: plastic, nonimmunogenic, watertight, highly porous, high surface area of fibers, cell growth stimulating, supportive for the survival of cells until they completely integrate with host tissues, conveniently replaceable, and adhesive. No ideal transplant materials can meet all the above demands. Biological, synthetic, and host tissues only supplement one another. Relevant studies have yet to be performed to obtain a more versatile and time and cost effective material that can satisfy all the requirements of modern neurosurgery. The existing results of preclinical studies have demonstrated that composite materials are similar to synthetic materials in terms of the strength and properties of biological tissues for the migration and proliferation of cells. In the future, they may become a promising alternative to biological substitutes.

Phthalates are typical air pollutants in vehicular environment since numerous synthetic materials that might contain phthalates are widely used to fabricate vehicle interiors (e.g., seat cushions, floor mats and dashboards). Hitherto, the importance of phthalate pollution in vehicular environment is not well-recognized because people spend only a small portion (around 8%) of their time in vehicles. In this study, the mass fractions of six phthalates in nine materials commonly used in Chinese vehicles (floor mats and seat cushions) were measured. Two phthalates, di-n-butyl phthalate (DnBP) and di-2-ethylhexyl phthalate (DEHP), were identified in most materials (the other phthalates were not detected). The emission characteristics of DnBP and DEHP from these materials were further investigated. The measured emission parameters were used as input for a mass-transfer model to estimate DnBP and DEHP concentrations in cabin air. Finally, the ratios between human exposures (via inhalation and dermal absorption from the gas phase) in vehicular environment and the total exposures in typical indoor environments (e.g., residences and offices) were estimated to be up to 110% and 20% for DnBP and DEHP, respectively. Based on these results, the vehicular environment might be a considerable site for human exposure to airborne phthalates.

Orthotics have been utilised by clinicians for many years to treat foot-related abnormalities. With advancements in material sciences, the footwear industry started utilising synthetic materials which have better and suitable properties. Clinicians, who prescribe foot insoles, need to have an extensive understanding of the properties and characteristics of insole materials, to make informed decisions to meet the patients' needs. This thesis showcases utilised techniques and systems to evaluate orthosis properties as well as current criteria to date. Researchers have utilised a variety of testing techniques to examine properties of insole materials including; bench testing, simulated in-shoe conditions, in-shoe testing, and finite element analysis. Even though, there is a great understanding of material properties with endless diverse composition and thicknesses of each material makes clinical recommendations on the choice of material an impossible task. As the footwear orthosis industry shifts the focus from material to design, some researchers explore various anisotropic materials to create a homogeneous insole that can support as well as relieve pressure on patient's feet.

Purpose Barriers to education in open and laparoscopic hernia repair technique include a steep learning curve and reduced theatre time for junior surgical trainees. This is particularly evident during the current COVID-19 pandemic. Simulation models may provide further opportunities for training in hernia repair outside of the traditional surgical apprenticeship model. Methods A systematic review was carried out following PRISMA guidelines to identify and evaluate simulation models in hernia repair. Of the 866 records screened, 27 were included in the analysis. These were assessed for face, content and construct validity, as well as their attempt to measure educational impact. Results Simulation models were identified comprising of animal tissues, synthetic materials and virtual reality (VR) technology. Models were designed for instruction in repair of inguinal, umbilical, incisional and diaphragmatic hernias. Twenty-one laparoscopic hernia repair models were described. Many models demonstrated validity across several domains, and three showed transferability of skills from simulation to the operating room. Of the six open hernia repair simulation models, none were found to have demonstrated an educational impact in addition to assessing validity. Conclusion Few models individually were able to demonstrate validity and educational impact. Several novel assessment tools have been developed for assessment of progress when performing simulated and real laparoscopic inguinal hernia repair. More study is required, particularly for open hernia repair, including randomized controlled trials with large sample sizes to assess the transferability of skills.

Spider capture silk is a kind of natural scaffold material that outperforms almost any synthetic material in its combination of strength and elasticity. Among the various kinds of silk threads, the cribellar thread is the most primitive type of prey-capturing thread found in spider webs. We analyze the functional organization of the sieve-like cribellum spigots and a specialized comb bristles of calamistrum for capture thread production in the titanoecid spider Nurscia albofasciata. It's outer surface of the cribellum is covered with thousands of tiny spigots, and this cribellum plate produces the non-sticky threads which composed of thousands of finest nanofibers. Average length of the cribellum spigot in N. albofasciata is 10 µm, and each cribellate spigot appeared as singular, long shafts with pagoda-like tiered tips. Each spigot has five distinct segments as a definitive characteristic of this spider. This segmented and flexible structure not only allows it to bend by itself and join together with adjacent spigots, but also enable to draw the silk fibrils from its cribellum with a row of leg bristles of calamistrum to form a cribellar prey capture thread.

Advancement in synthetic materials chemistry has brought about a new family of two-dimensional nanostructures (nanosheets) which have a variety of promising applications. In particular, synthesis o...

Re-epithelialization of wounds is a critical element of wound closure. Growth factors have been used in combination with conventional wound management to promote closure, but the method of delivery has been limited to the topical application of ointment formulations. Cytoactive factors delivered in this way have short resident times in wounds and have met with limited success. Here, we demonstrate that methods used to covalently immobilize proteins on synthetic materials can be extended to immobilize cytoactive factors such as the epidermal growth factor (EGF) onto the wound beds of genetically diabetic mice that exhibit impaired healing. Full-thickness splinted excisional wounds were created in diabetic (db/db) mice with a well-defined silicone splint to limit wound contracture. Wound surfaces were treated with a reducing agent to expose sulfhydryl groups and subsequently treated with EGF modified with a heterobifunctional crosslinker. This allowed for the covalent immobilization of the EGF to the wound surface. The conjugation chemistry was validated in vitro and in vivo. In a separate group of mice, wounds were topically treated twice daily with soluble EGF. The mice were evaluated over 11 days for wound closure. This covalent immobilization strategy resulted in EGF being retained on the wound surface for 2 days and significantly increased epithelial wound closure by 20% compared to wounds treated with topical EGF or topical vehicle. Covalent immobilization was not only therapeutically effective but also delivered a markedly reduced load of growth factor to the wound surface compared to topical application (when only 180 ng of EGF was immobilized onto the wound surface in comparison with 7200 ng of topically applied EGF over a period of 11 days). No adverse effects were observed in treated wounds. Results obtained provide proof of concept for the effectiveness of covalent immobilization in the treatment of dysregulated wounds. The covalent immobilization of cytoactive factors represents a potentially transformative approach to the management of difficult chronic wounds.

The paper describes qualitative methods of modern library collections (produced after the year 1800) survey in The National Library of the Czech Republic in Prague. Each book is primarily composed of paper sheets and bookbinding. In modern library collections bookbinding usually contains parts composed of synthetic materials. Different types of materials have different mechanisms of degradation. Therefore, the main objectives of this work are nondestructive identification of synthetic materials in bookbinding, their degradation processes, and methods of conservation, conditions of storage, and preventive care as well. Based on the preliminary results of the collection survey in the National Library of the Czech Republic, the most usual types of synthetic materials in bookbinding are cellulose nitrate, cellulose acetate, polyethylene, polyurethane, polymethylmethacrylate, and polyvinyl chloride, both of solid and plasticized type. For faster survey of the collections and deeper information is used new instruments for modern library collection survey and preservation – SurveNIR measuring system. SurveNIR measuring system is used for determination of paper properties and identification of plastic materials using chemometric and comparison with material standards. It can identify more than 45 different types of plastics. It is a nondestructive method, very fast, and it is possible to obtain results in a few seconds of measuring. The SurveNIR system was developed in the European project.

Background Current evidence is lacking regarding the optimum material required for cranioplasty in the pediatric population when native bone cannot be replaced. The aim of our survey was to examine current practice in Australia and New Zealand regarding pediatric cranioplasty material. Methods The online tool SurveyMonkey was used to survey 244 neurosurgeons in Australasia. The survey consisted of five questions concerning preference of material and donor origin for pediatric cranioplasty. Results Twenty-two neurosurgeons (9%) participated. The results indicate that with small skull defects (< 3 cm) in patients aged 0 to 2years, conservative management with observation alone is the preferred option (65%). In patients aged 3 to 10 years, autologous donor bone was the most popular option, whereas for 11+ years, hydroxyapatite (HA) was the material of choice, followed by titanium. For defects of more than 3 cm, autologous donor bone was preferred in under 11 years. In patients older than 11 years, titanium was the preferred choice (46.67%). The preferred donor origin for autologous cranioplasty in small skull defects (< 3 cm) was split calvarial grafts for all age groups. However, 68.42% of respondents managed those under 2 years conservatively. In large skull defects (> 3 cm), the preferred donor origin was split calvarial grafts for patients older than 3 years (48.3%). In patients aged 0 to 2 years, exchange cranioplasty was the preferred option when cranioplasty was performed. Conclusion The current practice in Australia and New Zealand is to use autologous donor bone in preference to synthetic materials for cranioplasty in children under 11 years. In children older than 11 years, hydroxyapatite and titanium are the materials of choice.

Biobased materials such as cellulose, chitin, silk, soy, and keratin are attractive alternatives to conventional synthetic materials for filtration applications. They are cheap, naturally abundant, and easily fabricated with tunable surface chemistry and functionality. With the planet’s increasing crisis due to pollution, the need for proper filtration of air and water is undeniably urgent. Additionally, fibers that are antibacterial and antiviral are critical for public health and in medical environments. The current COVID-19 pandemic has highlighted the necessity for cheap, easily mass-produced antiviral fiber materials. Biopolymers can fill these roles very well by utilizing their intrinsic material properties, surface chemistry, and hierarchical fiber morphologies for efficient and eco-friendly filtration of physical, chemical, and biological pollutants. Further, they are biodegradable, making them attractive as sustainable, biocompatible green filters. This review presents various biopolymeric materials generated from proteins and polysaccharides, their synthesis and fabrication methods, and notable uses in filtration applications.