Objective: Spontaneous intracranial hypotension (SIH) is typically caused by CSF leakage from a spinal dural tear, a meningeal diverticulum, or a CSF venous fistula. However, some patients present with classic orthostatic symptoms and typical intracranial imaging findings without evidence of CSF leakage despite repeated diagnostic work-up. This article aims to elaborate a hypothesis that would explain a pathologically increased orthostatic shift of CSF from the cranial to the spinal compartment in the absence of a CSF leak.Medical Hypothesis: The symptoms of SIH are caused by a decrease in intracranial CSF volume, intracranial hypotension, and downward displacement of intracranial structures. A combination of pathologically increased spinal compliance, decreased intracranial CSF volume, low CSF outflow resistance, and decreased venous pressure might result in a pathological orthostatic cranial-to-spinal CSF shift. Thus, in rare cases, intracranial hypotension may occur in the absence of CSF leakage from the dural sac.Conclusion: We propose a pathophysiological concept for the subgroup of SIH patients with typical cranial imaging findings and no evidence of CSF leakage. In these patients, reducing the compliance or the volume of the spinal compartment seems to be the appropriate therapeutic strategy. Orthostatic headache is the hallmark of headache attributed to spontaneous intracranial hypotension (SIH) as defined by the third edition of the international classification of headache disorders (ICHD-3) category 7.2.3 . The effOrthostatic headache without CSF leakage due to a pathologically increased spinal compliance was first discussed by Hunderfund and Mokri . However4 are displaying the physiological and pathophysiological concepts of CSF dynamics relevant for SIH that are going to be elaborated in detail in the following.In a person in a recumbent position, the CSF pressure is equal along the craniospinal axis. Thus, the opening pressure during lumbar puncture in a recumbent position corresponds to the ICP. When moving to an upright position, the pressure redistributes along the hydrostatic column from negative values in the cranial compartment to positive values in the spinal compartment . The zerC) is a measure of distensibility. It describes the ratio between changes in volume and pressure Craniospinal compliance  ml . Roughly2O in an upright position  or most often normal but not negative pressure. Thus, in the recumbent position, the intracranial pressure is positive, even in patients with CSF loss, which prevents brain sagging and explains the immediate relief experienced when the patient is lying down.Due to the equal distribution of pressure and fluid when in a horizontal position, the reduced CSF volume and the increased compliance have only a minor effect on ICP in the recumbent position. Measurements of opening lumbar pressure of SIH patients in the recumbent position demonstrate lower  a large number of meningeal diverticula , (2) durIn the case of an overall reduction in CSF volume, the state of the craniospinal compartment shifts to the left on the pressure-volume curve, leading to increased compliance . This mihigher intracranial CSF volume the proportion of CSF shifted is lower and more CSF remains in the intracranial space , CSF outflow resistance (Rout), and sagittal sinus pressure (Pss), as defined in Davson's equation: Clear benefit from unspecific epidural blood patch (EBP), upon repeated applications.These criteria do not provide direct proof and thus allow only the suspicion of internal SIH. Several problems need to be considered when trying to establish this diagnosis: First, because of the limited sensitivity of MR-myelography, CT-myelography, dynamic CT-myelography, and digital subtraction myelography, it is not possible to exclude an existing, but undetected small dural leak or CSF venous fistula. Thus, repeated and targeted work-up is required before considering the diagnosis of internal SIH.out, shows considerable variations and time-dependent behavior , seizures (4.5%), and infections (1.6%) . Hence, out by lumbar infusion testing, and CSF volumetry of cranial and spinal spaces in the diagnostic work-up of these patients.From a pathophysiological point of view, we also advocate measurement of ROf all the contributing factors described above, addressing the pathologically increased spinal compliance and thus the spinal volume reservoir is most feasible. A simple and well-tolerated method to achieve this is EBP , 38. TheAnother therapeutic option to reduce compliance of the spinal compartment is reduction of prominent meningeal diverticula or dural reduction surgery. The principle of the surgery is to reduce the volume capacity of the spinal CSF reservoir and thus to decrease the compliance of the spinal compartment. Consequently, a smaller volume of CSF is shifted from the cranial to the spinal compartment when assuming an upright position. Schievink et al. demonstrated a positive effect of lumbar dural reduction surgery in a patient with intractable SIH but no evidence for CSF leakage . This isWe propose a pathophysiological concept for the subgroup of SIH patients with typical cranial imaging findings and no evidence of CSF leakage after repeated and meticulous work-up. Pathologically increased spinal compliance as the main factor, in combination with predisposing factors such as decreased total and intracranial CSF volume, low CSF outflow resistance, and decreased venous pressure might cause a pathological orthostatic CSF shift resulting in intracranial hypotension and brain sagging even in the absence of CSF leakage. The compliance of the spinal compartment seems to be the most attractive therapeutic target.The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author/s.JGo, LH, JB, and AR: design and conceptualized study and drafted manuscript. CJ, IZ, EP, JGr, and TD: revised manuscript for intellectual content. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


The advancement of natural-based biomaterials in providing a carrier has revealed a wide range of benefits in the biomedical sciences, particularly in wound healing, tissue engineering and regenerative medicine. Incorporating nanoparticles within polymer composites has been reported to enhance scaffolding performance, cellular interactions and their physico-chemical and biological properties in comparison to analogue composites without nanoparticles. This review summarized the current knowledge of nanoparticles incorporated into natural-based biomaterials with effects on their cellular interactions in wound healing. Although the mechanisms of wound healing and the function of specific cells in wound repair have been partially described, many of the underlying signaling pathways remain unknown. We also reviewed the current understanding and new insights into the wingless/integrated (Wnt)/β-catenin pathway and other signaling pathways of transforming growth factor beta (TGF-β), Notch, and Sonic hedgehog during wound healing. The findings demonstrated that most of the studies reported positive outcomes of biomaterial scaffolds incorporated with nanoparticles on cell attachment, viability, proliferation, and migration. Combining therapies consisting of nanoparticles and biomaterials could be promising for future therapies and better outcomes in tissue engineering and regenerative medicine. Nanoparticle-based therapies have a wide range of applications nowadays, and advances in nanotechnology offer novel solutions to disease problems. Recently, nanodelivery systems are rapidly developing new materials in the nanoscale range that are employed to deliver therapeutic agents to specific targeted sites in a controlled manner. It has offered numerous exciting possibilities in healthcare, and a few products are now available on the market. Nanotechnology is essential technology in the 21st century, with an atomic group at the nano-scale size of 1–100 nm ,4. The nBiomaterials are classified into two categories, the first of which includes synthetic polymers including polyvinyl alcohol (PVA) , polyethStrategies for applying the biomaterials to cure or treat diseases can be achieved in one of two approaches: either with the features of the nano-scaled materials used, or with the materials as a carrier molecule, to deliver active compounds pharmaceutically to the specific site . Up untiA systematic computerized literature search was conducted to determine relevant studies that reported the use of various types of nanoparticles embedded with natural-based biomaterials, and their biological cell effects. The systematic review was compiled based on the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines to ensure the quality and transparency of the study . Four daThe search strategy or searching method used two sets of keyword combinations, which were: (1) nanoparticle* (to obtain nanoparticle or nanoparticles) or particle* (to obtain particles or particles) or biomaterial*  or material*  or natural material* ; and (2) cellular pathway* (to obtain cellular pathway or cellular pathways) or signaling pathway*  or biomedical application*  or regenerative medicine application* (to obtain regenerative medicine application or regenerative medicine applications). The comprehensive search strategy is summarized accordingly in Due to limited translation resources, we only considered published research articles written in English. The research articles that reported the effect of nanoparticle-incorporated natural-based biomaterials, with the main priority of biomedical engineering or regenerative medicine applications, were included in this review, including the different types of nanoparticles and biomaterials. Moreover, the articles that revealed the cellular functions associated with activated signaling pathways in cells, including fibroblasts, keratinocytes and endothelial cells, were also reviewed.The exclusion criteria included research articles that were submitted or written in a language other than English. All editorials, conference papers, news, case reports, review papers, and letters were also excluded.All research articles were screened in three steps to meet the requirement of this systematic review. Firstly, a title screening step was applied to remove titles that did not match the inclusion criteria. Secondly, an abstract examination of the remaining papers was conducted, to remove inappropriate articles based on the inclusion criteria. The final step included was removing article papers that did not focus on the biological cell effects (activated pathways). A keyword search returned 91 articles that might potentially be relevant. Once selected, a total of 15 articles were chosen for review after determining if they met the criteria. A flow chart of the article selection process is shown in The review was accompanied by a methodological approach using the critical evaluation for systematic reviews . Both thAmong the selected articles, all articles included nanoparticle-incorporated natural-based biomaterials and reported on biological cells in biomedical applications, especially in tissue regeneration and regenerative medicine. All of the studies were published between March 2017 and January 2021. Generally, the selected research articles were identified and discussed for the studies that involved different types of nanoparticles and natural-based biomaterials. We also reviewed the effects of the incorporation of nanoparticles on cellular functions, including cell viability or cytotoxicity, cell proliferation, cell migration, intracellular antibacterial properties, and the main priority in tissue engineering applications involved in wound care management. We also included the effects of the incorporation of nanoparticles in biomaterials on the mediation of cellular signaling pathways towards wound healing, tissue engineering and regenerative medicine. A summary of all of the studies involved is displayed in a data extraction table in The outcomes from the review highlighted the types of biomaterials, fabrication format and advantages of various biomaterials incorporated with nanoparticles for tissue engineering applications. The groups of biomaterials used were cellulose, collagen, and natural polymers including chitosan and alginate. Four formats for the fabrication of nanoparticle-incorporated biomaterials were reported in fifteen research articles, including (1) (n = 6) nanofibers ,42,46,52The use of therapeutic agents has been formulated over time in drug development . HoweverRelying on the nature of the wound healing mechanism, a well-defined pore size of nanoparticles with a highly porous structure can regulate the migration rate of cells and facilitate biological processes, including cellular activity and viability. These features consist of benefits in terms of being able to promote matrix swelling and absorption of wound exudates. Therefore, the generation of endothelial and fibroblasts cells was activated, thus enhancing tissue repair. There are different types of fabrication available, and most of the materials used are naturally derived from polymer and the ECM of tissues which possesses different physicochemical and biological properties. Fabrication technology is widely used to produce scaffold from biomaterials, either synthetic or natural . VariousWith the merits of fungicidal ,58,59, aElectrospinning technology becomes an effective method and reliable technique for producing microfiber or nanofiber ,70. CompThese findings were similar to those summarized by El-Aassar et al. , where t2 transmission, preventing microorganisms, and accelerating epithelialization [New nanoparticle- or nanomaterial-based treatments for skin lesions have been developed over the years. The nanocomposites are generally used as 3D nano-fibril structures called scaffolds. These can be divided into porous materials, colloids, copolymers, and gels . Plenty lization ,83. It hlization . Similarlization . It was lization  reportedlization .The combination of metal nanoparticles in hydrogels is a newly emerging area of research in wound healing, tissue engineering, and regenerative medicine . A hydro2 nanoparticles, loaded in PVA to produce highly stretchable composite hydrogels. The authors confirm that there are synergistic effects in terms of extensibility due to the integration of both nanoparticles in the polymer network [Presently, the concept of forming an inorganic–organic framework with improved properties has led to innovation in tissue engineering scaffolds. There are ways to fabricate metallic nanoparticles incorporated into crosslinked hydrogel composites, as summarized in  network . In addi network .S. aureus and P. aeruginosa were also identified. Fascinatingly, the in vivo results showed that the PEG-AuNPs’ hydrogel efficiently healed the wound and completed the wound closure without scars. According to the positive effect of impregnated polymeric hydrogels with nanoparticles on the proliferation of human fibroblasts, they were able to find potential in skin tissue regeneration.Moreover, for the study conducted by Zulkifli et al. , the antS. aureus and E. coli. The film was also allowed enrichment in cell adhesion and proliferation, due to the specific concentration of nanoparticles [Combined with available treatment strategies, films with a homogeneous polymeric structure were also beneficial in biomedical fields. Recently, it has been suggested that incorporating therapeutic drugs or nanoparticles into the films can enhance the drug’s therapeutic effect and its effectiveness without altering the function of the film, which would be a good idea for skin tissue engineering . Therefoarticles . Similararticles ,102. Morarticles , the carFrom the literature search, the findings of the studies were discussed on the effect of the incorporation of nanoparticles into biomaterial scaffolds towards biological cellular pathways. We focused on the observation of its application in wound healing, tissue engineering, and regenerative medicine. A variety of natural polymers have been successfully engineered to associate with different kinds of nanoparticles, resulting in improved efficiency. For this reason, a superior understanding is required of the therapeutic effects of the biomaterial system with intercellular, transcellular, and other activated signaling pathways.The study of the effects on cell toxicity of nanoparticles embedded in the biomaterials is of great significance. There has been increasing evidence that the biological properties of the scaffold affect various types of cellular behavior, including cell compatibility, viability, proliferation, and migration . To addrDue to special distributions of incorporated nanoparticles within the scaffolds in skin tissues, scientists also studied the effect of nanoparticles on cell proliferation and migration to skin cells. In the application of wound healing, recent studies based on the in vitro scratch experiments and in vivo animal studies have demonstrated positive results. The incorporation of nanoparticles into natural-based polymeric biomaterials significantly promoted cell proliferation and migration, which are the biological functions crucial for wound site closure, as well as restoration of barrier function ,107,108.Even though there is no determination of signaling pathways in the selected articles, we have accumulated evidence of the activation signaling pathways that are critically involved in proliferation, migration cells, and wound healing. To the best of our knowledge, the activation of the Wnt/β-catenin signaling pathway plays a vital role in the proliferative phase of wound healing and tissue regeneration after injury. The Wnt/β-catenin signaling pathway is activated in the dermis of the wound bed immediately after skin injury. β-catenin is a subunit of the cadherin protein complex, where Wnt plays a specific role in the regulation of β-catenin function ,112,113.On the other hand, the TGF-β pathway is also involved in skin wound healing and dermal fibrosis. It is elaborated differently in the regulation of healing rate, which depends on the isoforms . For exaThe findings from this evidence-based review reported a trend of using nanoparticles incorporated with natural-based biomaterials for tissue engineering and regenerative medicines. However, there are still limits on the study of the signaling pathways. Therefore, we discussed the essential characteristics and functional application of nanoparticle-incorporated natural-based biomaterials, the biology of cellular functions associated with multiple signaling pathways in mediating wound healing, and tissue engineering applications as well. Polymer natural-based biomaterials show high benefits that are well-documented in the literature ,125. A lHowever, this combination therapy of nanoparticle-biomaterial scaffolds is clinically limited, especially in overcoming the ongoing challenge of the uncontrolled release of nanoparticles from the scaffold; it is also of concern. The nanoparticles themselves may not just be directly taken up by the cells in exposed organs, but may also translocate to the other organs, resulting in undesirable toxicity . With thIt is important to determine the molecular and cellular mechanism, specifically in normal skin repair. Early stages of wound healing include hemostasis and activation of keratinocytes and inflammatory cells. The intermediate stage involves proliferation and migration of keratinocytes, proliferation of fibroblasts, matrix deposition, and angiogenesis. Late-stage healing involves remodeling of the ECM, resulting in scar formation and restoration of the barrier. This spatiotemporal process is tightly controlled by multiple cell types that secrete numerous growth factors, cytokines, and chemokines to achieve closure and functional restoration of the barrier . In addiNevertheless, none of the articles presented human clinical trial data, implying the efficacy of the nanoparticle-incorporated biomaterials. Since the development of biodegradable nanotechnologies has also increased in the use of naturally based biomaterials towards clinical applications, it encourages the interaction between cells and biomaterials. We recommend that more researchers investigate and address in vivo studies and clinical trials of the functional applications of nanoparticle-loaded natural biomaterials in tissue engineering and regenerative medicine.In conclusion, this evidence-based systematic review generally shows positive outcomes towards nanoparticles, which are useful for therapeutic delivery of biomedical applications, including in wound healing. All of the above-reported results strongly indicate that natural-based products that incorporate nanoparticles are effective and safe for use in treatment. However, there are still some health hazard concerns, especially regarding toxicity due to uncontrollable use and release. With this in mind, the incorporation of nanoparticles with natural-based biomaterials should be considered, to make the use of nanoparticles’ slow-release, easier, safer and more environmentally friendly. This study also identifies mechanism through which nanoparticle-incorporated biomaterials affect cellular and molecular signaling pathways. Our findings suggest that Wnt/β-catenin signaling pathways play important roles in tissue regeneration, specifically in cutaneous repair. The interaction between the two pathways might play a vital role in the regulation of healing. By understanding the mechanism involved in the signaling pathways for wound healing, we can identify new targets for the development of regenerative wound healing using nanoparticles incorporated into natural-derived biomaterials, combined with the therapeutic agents. For a future perspective, we can design new technologies to mimic native tissue with 3D networking as effective wound healing therapies, if we better understand these complex interactions. This also includes the cost effectiveness and sustainability of the technology with the use of intelligent biomaterials that can revolutionize the field of tissue engineering and regenerative medicine in the future.To date, bioscaffold-based strategies developed for therapeutic applications present many challenges, and also new opportunities. Recent advancements in natural-based biomaterial synthesis have enabled researchers and scientists to incorporate many nanoparticles, thus facilitating better tissue regeneration with fewer toxicity effects. Despite these recent improvements, more efforts should be made to advance the fabrication of bioscaffolds through a combination of nanoparticles and biomaterials. Tailor-made therapies will become increasingly relevant in coming days. In the future, more clinical trials and in vivo studies will help us to realize the widespread commercial use of natural-based scaffolds incorporating nanoparticles with cost-effectiveness and ease of use.


Impetuous urbanization and population growth are driving increased demand for plastics to formulate impeccable industrial and biomedical commodities. The everlasting nature and excruciating waste management of petroleum-based plastics have catered to numerous challenges for the environment. However, just implementing various end-of-life management techniques for assimilation and recycling plastics is not a comprehensive remedy; instead, the extensive reliance on finite resources needs to be reduced for sustainable production and plastic product utilization. Microorganisms, such as bacteria and algae, are explored substantially for their bioplastic production repertoire, thus replacing fossil-based plastics sooner or later. Nevertheless, the utilization of pure microbial cultures has led to various operational and economical complications, opening the ventures for the usage of mixed microbial cultures (MMCs) consisting of bacteria and algae for sustainable production of bioplastic. The current review is primarily focuses on elaborating the bioplastic production capabilities of different bacterial and algal strains, followed by discussing the quintessence of MMCs. The present state-of-the-art of bioplastic, different types of bacterial bioplastic, microalgal biocomposites, operational factors influencing the quality and quantity of bioplastic precursors, embracing the potential of bacteria-algae consortia, and the current global status quo of bioplastic production has been summarized extensively. The cataclysmic repercussions of disposable plastics on the environment have been a great deal of concern in today’s scenario. The perennial nature of petroleum-based plastics instigates a conspicuous challenge for the ecological community in terms of their eradication and recovery. The recovery and recycling of plastic waste immensely depend on the method of disposal of plastic waste. The mixed disposal of plastic waste makes its recovery difficult and less energy efficient . SeveralThe hike in plastic production has considerably surpassed any other human-made objects in the past 65 years. The complex nature of petroleum-based plastic leads to the deterioration of the environment at the expense of economic benefits. A seismic shift in the environmental policies effectuated by the overwhelming and escalating plastic pollution has redirected the prevailing maneuvers toward the advancement of native low-carbon, circular economies, with strict landfill waste regulation, systematic recycling and recovery methodologies, and compulsory usage of bioplastics for the production of innumerable commodities . In ordeBacillus sp., Azotobacter sp., Alcaligenes sp., Pseudomonas sp., methylotrophs, and Cupriavidus nectar as well as algal strains Spirulina platensis, Nostoc muscorum, Synechococcus sp., etc., have been explored extensively for the production of biopolymers . Major components of the cells which include protein, polysaccharides, lipids, amino acids , and polpolymers .Taking into consideration the prevailing plastic pollution and augmenting demand for plastic products, emphasizes on employing the biorefinery framework for cultivation of microalgae. Furthermore, while focusing on the biorefinery approach, it encompasses maneuvering the sustainable conversion of cell biomass into a spectrum of bio-based marketable products  to make microalgal biomass an economic-friendly and feasible feedstock for replacing the conventional plastic . Life cy2), methane (CH4), and syngas can also be used as an efficient substrate for the production of bio-based products, which further aids in the sequestration of greenhouse gases as well as in wastewater treatment  or mixed microbial cultures (MMCs) to make the process cost-effective and strengthen the phenomenon of circular bioeconomy.Polyhydroxyalkanoate is a metabolite produced by some microorganisms as a storage product, which also acts as a shield against adverse environmental stress. Enhanced metabolic engineering methodologies have paved the way for exploring and exploiting various PHA biosynthesis pathways, which leads to the formation of different modified PHAs or bioplastics with specific material properties, beneficial for biomedical and industrial applications, such as high-value medical equipment (including sutures and drug delivery), or low-value materialistic bioplastic , medium-chain-length PHAs (C6-C14), and long-chain-length PHAs , a short-chain-length PHA, has been the most widely characterized and explored bioplastic due to its early discovery in the year 1926 . PHB copPhaA, 3-ketothiolase to block the accumulation of PHA. This redirects the flux of acetyl-CoA toward the Krebs cycle to accomplish cell growth and energy production. Conversely, when nutrients including phosphorus and nitrogen are not sufficient and an excess of carbon is added in the microbes’ growth environment, a low amount of CoA is produced, which cannot obliterate the PHA biosynthesis enzyme. Consequently, channelizing the acetyl-CoA toward the PHA biosynthesis pathway stimulates PHA aggregation  responsible for culminating three essential reactions. At first, enzyme PhaA, i.e., β-ketoacyl-CoA thiolase, eventuates the reaction between two acetyl-CoA molecules for acetoacetyl-CoA formation. Subsequently, an enzyme PhaB, which is NADPH-dependent acetoacetyl-CoA dehydrogenase, catalyzes the reduction of acetoacetyl-CoA into (R)-3-hydroxybutyryl-CoA monomer. Eventually, enzyme poly-3-hydroxybutyrate polymerase, encoded as PhaC, instigates the polymerization of (R)-3-hydroxybutyryl-CoA monomer into poly-3-hydroxyalkanoate , which further catalyzes the biosynthesis of PHA via the fatty acid de novo biosynthesis pathway. Whereas, when oxidation of carbon sources via the fatty acid β-oxidation pathway takes place then enzyme (R)-specific enoyl-CoA hydratase, PhaJ catalyzes the oxidization of enoyl-CoA to (R)-3-hydroxy acyl-CoA, which eventually acts as a target precursor for enzyme PhaC, PHA synthase, for PHA biosynthesis  has been delineated to influence PHA production. Even the mechanical properties of PHA material get modified based on the nutrients present in the media and it eventually characterizes the use of bio-based material in different fields of biotechnology. PHB yield of Paraburkholderia xenovorans LB400 was grown in three different carbon sources namely, glucose, xylose, and mannitol. The study concluded that PHB produced with glucose and xylose had similar molecular weight, which is near to commercially available PHB, whereas PHB produced in mannitol supplementation had double Mw as compared to control and other carbon sources. The study also concluded that carbon sources not only affect the quantity of PHA production but also the molecular weight of bioplastic , which can be used in the pharmaceutical industry. NADH plays a major role in the assimilation of pentose and hexose sugars. Activation of glucose transporters releases NADH, which in turn activates the accumulation of PHA via inducing conversion of acetyl coA  PHB. Therefore, deviation in the light periodicity integrated with varying luminous intensities and involvement of pentoses in the metabolic pathway has proven to stimulate and boost the PHB accumulation capacity of Chlorella. The uptake of organic carbon is highly dependent on photoperiod and light intensity. Light phase triggers the enzymes responsible for autotrophic growth hence blocking the utilization of carbon sources but during the dark cycle of mixotrophy, it starts assimilating organic carbon hence converting the flux toward PHA synthesis , polyamides (comprise of amino acids intertwined by peptide linkages), polyesters (consist of ester-bond linked hydroxy fatty acids), and polyphosphates (composed of inorganic phosphates connected by anhydride bonds), are produced by different bacterial species. These have been made and utilized substantially on a commercial scale while considering the recent advances in bioengineering methods and molecular techniques  and excess carbon supplemented environment , when supplemented with fructose as carbon supply, can potentially accumulate 79% of the dry cell mass of PHB under optimal conditions  or hydrogen or ferrous ions (purple non-sulfur bacteria PNSB) as an electron acceptor during photosynthesis . They caRhodovulum visakhapatnamense accumulated up to 30% accumulation and Rhodovulum sulfidopilum when exposed to only acetate in seawater accumulated 9% PHA  which was utilized by hydrogen . They cahydrogen .It is evident that the bioplastic precursors derived from bacteria prove to be an imperative constituent of bioplastic commodities. There are several plastic industries worldwide, manufacturing bioplastic products from the precursors derived from bacteria, and the products have the potential of replacing fossil-based plastic. However, large-scale production of bacterial bioplastic has started from past few years and to make the process feasible as that of conventional plastic production, more research needs to be performed in this domain. The factors affecting the accumulation of bioplastic precursors, their extraction and purification process, and at last their transformation into bioplastic commodities need to be investigated on a large scale. The evaluation needs to be done to explore the bioplastic production capability of pure strains as well as MMCs. The biorefinery approach for the production of bacterial bioplastic along with other essential bioproducts derived from bacteria needs to be scrutinized and exercised in order to make the process techno-economically feasible. Additionally, systems analysis incorporating LCA and techno-economic analysis must be investigated for determining the sustainability of bacterial bioplastic production.2, and water, are processed through microalgae metabolism to form bioenergy products. Because of their high cell proliferation rate, microalgae’s conversion efficiency is postulated to be 10 to 50 times higher than that of terrestrial plants. Thus, the microalgal land footprint required for bioenergy production is significantly less than plants. The most prevalent and topical agenda in the field of algal biotechnology is accomplishing the tremendous opportunities catered by algal biomass and their widespread biochemical portfolio. Due to their exceptional potential of assimilating photosynthetic carbon, microalgae are enunciated as a highly efficient form of cell biomass produced and has immense potential to engage in a clean energy future , accompanied by the acquisition of imperative biochemical constituents, including lipids  is the highly explored and most expedient building block of microalgae bioplastic due to its easy biodegradation, catalyzed by enzymes  and materials, such as polyvinyl chloride (hydrophobic), polyethylene, and polypropylene. The algal composite is characterized as a composite of high tensile strength and thermal stability due to the presence of Chlorella grains and their binding capability , and co-production of bioplastic along with other valuable products in a biorefinery setup needs to be envisioned to accomplish the objective of 100% bio-based plastic.In a nutshell, algal bioplastic production is still in its infancy as compared to bacterial bioplastic production. Besides, the waste to bioenergy conversion potential of algae has not been explored to the fullest for the treatment of waste  coupled with the production of bioplastic precursors. Even co-production and extraction of different bioproducts in an algal biorefinery have been researched evidently, but the accumulation of bioplastic in a biorefinery setup has not yet been reviewed. The potential of different algal strains, their growth, utilization of waste  entities into the algal blends of thermoplastic nature. Equivalently, employing wastewater as a nutrient substrate for algae-based plastic production has also resulted in a beneficial strategy for synthesizing biodegradable bioplastics in an economically efficient manner. Indeed, carrying out concurrent research while considering algae as a promising and harmless bioplastic candidate can aid in diminishing the dependency on fossil fuels, improving the quality of plastic produced, and can help in minimizing the negative impact of petroleum plastics on the environment.Although microbial community has been determined as a proficient candidature for bioplastic production; however, just optimizing the growth and accumulation of bioplastic precursors at lab. Scale is not sufficient enough for commercialization of bioplastic material. Scaling up of lab-scale parameters on pilot scale have frequently let down, reason being the added factors related to type of pilot-scale plant. Pilot-scale plant includes two categories: closed bioreactors and open pond systems.Halomonas campisalis MCMB-1027 was grown in a 14 L reactor and accumulated 41% PHA under optimum agitation and aeration. Optimized dissolved oxygen level (DO) further increased accumulation up to 56%. This optimization helped developing a correlation for upscaling up to 120 L fermentor  for the production of building blocks of bioplastic, such as Polyhydroxybutyrate or polyhydroxyvalerate, has been proposed. The MMC utilization caters to the reduced bioplastic production cost owing to the consumption of inexpensive heterogeneous feedstocks complemented with the open cultivation conditions, neglecting the need for sterilization or stringent control regulations. Volatile fatty acids including, butyrate, propionate, acetate, and valerate obtained from the fermentation of sewage streams are known to be the best precursors utilized by MMCs for PHA production . CertainHowever, to generate an elevated amount of PHA, the microbial genera present in the MMC needs to be specified and optimized. For the selection of microbes, the culture has been transiently fed by obeying the feast and famine regime, which comprises of an intermittent feeding strategy, delineated as the enrichment of the culture with external carbon substrate (Feast) for a particular period of time, followed by the depletion of the carbon substrate (Famine) in the alternative time period. These feast and famine cycles are repeatedly practiced, which favors cell growth, as well as accumulation of storage molecules, such as PHA during the feast cycle and later gets consumed during the famine cycle. Thus, microorganisms having high PHA storage capacity will ultimately survive and grow, becoming the microorganism of choice for inclusion in the MMCs .Furthermore, the operating conditions and the composition of the substrate also play a significant role in the selection of diverse microbial species ,b,c. DifAs per the aforementioned literature, besides bacteria, algae have also been in the league of PHA production. Based on aforementioned facts, the algae-bacteria consortiums have been ascertained and reported to have the potential for wastewater treatment accompanied by the production of different biotechnologically essential bioenergy products .According to the literature study done, the highest energy-intensive prerequisite of MMCs recognized is the supply of proper aeration for fulfilling the requirement of oxygen (an electron acceptor) because the PHA content accumulated in an aerobic environment (75%) is substantially high as compared to the PHA content gathered in anaerobic/aerobic environment (37%). However, the requirement of aeration ultimately increases the operation cost involved in the PHA production by MMCs .Ralstonia eutropha can be considered. R. eutropha independently under the supplementation of VFAs derived from food waste is known to accumulate approximately 52% PHA copolymer  for ameliorated polyhydroxyalkanoate production PHA; , 2016.Halomonas boliviensis bacterium was capable of metabolizing sucrose secreted by algae, Synechococcus elongatus CscB. It was reported that the bacteria in consortia were able to accumulate about 31% dry cell weight of PHB, with the productivity of 28.3 mg PHB L−1D−1  and its widespread applications in different industrial fields, such as food services and packaging. Moreover, increasing awareness regarding the benefits of biocompatible and biodegradable plastic, formulation of government norms to stimulate and acknowledge eco-friendly techniques, and ever-augmenting fossil-fuel prices have invigorated the commercial diversion toward the production of bioplastic elements.The worldwide spread of bioplastic business is still subordinate as compared to the petroleum-based plastic market. Different bioplastic-producing plants are situated in different parts of the world, including Italy, Brazil, the United States, China, and others. Indeed, various industries are in the business of bioplastic production, especially PHA thermoplastic material.It has been evident that microalgae have proved to be a superlative candidate for the production of bioplastic but needs to be explored further in order to achieve commercial production of bioplastic emanated from microalgae independently or in consortium with bacteria. A substitute for a plastic bottle was also prepared by the composition of red algae powder and water . Therefovia bacteria being commercialized, a cost-effective, sustainable large-scale venture for the synthesis of bioplastic, especially PHA bioplastic, is still in its early years. The challenges faced in the process include the need for expensive carbon sources, operational cost to maintain the process control parameters, low yield of a metabolite of interest, difficulty in achieving considerable productivity, and downstream processing steps. Whereas, usage photosynthetic organisms are still in their early course nut they have immense leeway for achieving a greater place in bioplastic industries. From the past few decades, microalgae and cyanobacteria are also under surveillance for evaluating their potential of bioplastic precursor accumulation or for direct usage in bioplastic production. Nevertheless, the methodologies evolved for the production of algal bioplastic are not economically feasible and environmentally sustainable. Additionally, many technical and procedural complications occur while scaling up bioplastic production emanated from algae.Microbes are scrutinized substantially for the synthesis of sustainable bioplastics and had proven to be a magnificent source of bioplastic precursors that could be utilized further to produce biocompatible and carbon-neutral biodegradable products. As per literature, bacteria have been reported to accumulate about 80–90% of PHA when subjected to optimal conditions. Currently, bacteria are consistently exploited to commercialize biodegradable and sustainable bacterial bioplastic, and many industries are doing business out of it. Despite bioplastic production via various microbes individually, a consortium approach seems to be a light in the dusk. In recent years, different MMCs are under observation to uncover their bioplastic production potential, either by tweaking certain culture conditions or by metabolic engineering approach. The practice of utilizing photosynthetic MMCs composed of bacteria and algae consortia or different photosynthetic bacteria, accompanied by the consumption of wastewater or byproducts of various production processes like molasses, grape pomace, olive pomace, and crude glycerol as a substitute for pure organic carbon source, will prove to be an efficacious perspective for the production of economically feasible, environmentally sustainable, and biodegradable bioplastic. PHA produced by MMCs can also have a greater composition for a better composition and mechanical properties.Keeping in mind the various pro and cons of PHA production A biorefinery approach can also help overcome the cost and sustainability crisis in commercialization of PHA as bioplastic. Tailor-made consortium of microalgae and photosynthetic bacteria will attain high productivity of PHA as well as precursors of bioenergy molecules to spread out the burden of scaling up. In a nutshell, promising biodegradable bioplastic constituents can be derived from algae and bacterial consortia as an alternative for replacing traditional fossil-based plastics, ultimately unraveling the strategy of reducing plastic pollution as well as the burden on the finite resources.KS worked on conceptualization, methodology, and visualization. RS gave her contribution in data curation and writing the original draft. RN reviewed and edited the manuscript. KB supervised and conceived the manuscript. Manuscript was critically reviewed and approved by all the authors.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Forensic biomechanics gradually has become a significant component of forensic science. Forensic biomechanics is evidence-based science that applies biomechanical principles and methods to forensic practice, which has constituted one of the most potential research areas. In this review, we introduce how finite element techniques can be used to simulate forensic cases, how injury criteria and injury scales can be used to describe injury severity, and how tests of postmortem human subjects and dummy can be used to provide essential validation data. This review also describes research progress and new applications of forensic biomechanics in China.The review shows the main research progress and new applications of forensic biomechanics in China.The review introduces eight cases about the application of forensic biomechanics, including the multiple rigid body reconstruction, the finite element applications, study of mechanical properties, traffic crash reconstruction based on multiple techniques and analysis of morphomechanical mechanism about blood dispersal.Though forensic biomechanics has a great advantage for the evaluation of injury mechanisms, it still has some uncertainties owing to the uniqueness of the human anatomy, the complexity of biological materials, and the uncertainty of injury-causing circumstances. With the progress of the contemporary rule of law, forensic science plays an increasingly important role in legal practice and has gradually become an important means of ensuring judicial justice. Forensic scientists frequently encounter trauma related cases in practice and need to explain the causes of injury, such as the type and strength of external forces and the biomechanisms of injury . HoweverRecently, biomechanics has been gradually applied in the field of forensic science. Interdisciplinary research has contributed to the rapid development of biomechanical techniques and the creation of a series of related disciplines in medicine, sports science, accident reconstruction, healthcare, and dentistry. Forensic biomechanics is evidence-based science that applies biomechanical principles and methods to forensic practice. Forensic biomechanics focuses on exploring the causation of forensic phenomena that are often deciding factors in injury, civil, and criminal cases. Forensic biomechanics has become an important branch of forensic science, providing the means for more objective and quantitative forensic investigations, and it is one of the research areas of forensic science that still have great potential for development .This review highlights current applications of forensic biomechanics using material properties of human tissue, injury criteria, injury scales, and injury reconstruction, and describes research progress and new applications of forensic biomechanics in China.Biomechanics: Mechanical Properties of Living Tissues [Since the 1970s, the rapid development of transportation has led to an increasing number of road traffic accidents, which have fostered the integration of forensic science and biomechanics. Meanwhile, computer processing capabilities have rapidly increased allowing the use of computer technology to solve biomechanical forensic problems . Marked  Tissues  by Fung  Tissues . Forensi Tissues , 4.Multi-body modelling uses rigid bodies and joints to simulate the mechanical properties of an object. The geometry of the multi-body model is usually modelled using ellipsoids and/or facets. For multi-body human body models, different contact properties and joint motion properties are usually defined to simulate the mechanical characteristics of the human body regions and joints. Similarly the geometric and mechanical characteristics of vehicle fronts can also be modelled using multi-body systems. The MADYMO pedestrian models and Chalmers pedestrian model (CPM) are the main ellipsoid multi-body human body models . They weFE modelling is an important tool for injury reconstruction and mechanism analysis in forensic biomechanics. FE models are extremely sensitive to parameters such as the mathematical constitutive and corresponding material properties of human tissues, and human material testing has become the basis for applying forensic biomechanics. Stress-strain curves of biological tissues are generally nonlinear, anisotropic, and viscoelastic, and non-Newtonian fluid models may better represent body fluids . The matThe loading tests on PHMS provide data that are fundamental for biomechanical modelling and have become essential validation tools in the development of human FE models. Data from PHMS experiments conducted by Nahum et al. , YogananIwamoto et al.  releasedAt present, many forensic scientists all over the world have applied the biomechanic method for simulation and analysis of real cases. Raul et al.  used theResearch into biomechanics started late in China. Tsinghua University, Jilin University, Hunan University, Third Military Medical University and other research institutions started to build multi-body model and FE model or to applicate business model since 2002 , 79, 80.In China, the use of e-bikes and public bicycles has significantly increased because they are convenient and low cost, which has also caused traffic fatalities among cyclists to increase. Cyclists are not allowed to ride their bicycles when crossing the road or travelling against the flow of traffic; they must dismount and walk instead. Therefore, the pre-impact condition of a cyclist is an important evidence when assigning responsibility for an accident between a cyclist and the driver of a vehicle. In addition, traffic police must identify the driver responsible for each accident. Traditional approaches to accomplish this are based on vehicle traces, victim injuries, and accident traces. Recently, multi-body simulation models have been applied to reconstruct real-world road accidents. Some examples using multiple rigid body simulation in traffic accident cases are presented.Case 1 is a vehicle–bicycle accident and the key was to identify the pre-impact condition of a cyclist  . Multi-bIn Case 2 and Case 3, the aim was to identify the driver and passengers in scooter or motorcycle-related traffic accidents . In CaseCase 3 was a motorcycle–vehicle rear-end collision. Simulated MADYMO kinematics correlated well with accident data in this case ; the impTraumatic brain injuries (TBIs) are a major cause of death in forensic cases . The mecA 50-year-old man died while fighting with others. The police were confused about whether the head injuries had been caused by a punch or by impact with the ground. AFS used an FE model of the head to simulate scenarios involving punches and ground impacts. The simulation results  showed tA woman riding a motorcycle collided with a pedestrian and fell to the ground. Several minutes later, another vehicle hit the motorcyclist. The autopsy results showed that the fatal injury was a basilar ring fracture around the foramen magnum, brain stem and cervical spinal contusions, and diffuse subarachnoid haemorrhages. The key question was to identify whether the fatal ring fracture had been caused by the initial fall or the subsequent vehicle impact. In this case , THUMS wThe lower extremity is a common site of injury in traffic accidents. Exploring the primary mechanisms of pelvis, femur, and lower extremity injury can improve the quality and accuracy of forensic investigation. AFS developed an FE model of the pelvis that included bilateral iliac bones, the sacrum, bilateral femurs, joint cartilage, and ligaments using DICOM format computed tomography (CT) data. Loads were applied to the trochanteric surface of the right femur to simulate a side impact . The resA woman had accused a driver of hitting and injuring her leg with his car, but the driver said that the injury had been caused from a fall to the ground when the woman climbed over the railing. AFS used an FE model of the lower limb to simulate scenarios involving the lower limbs being struck by the bumper of a car and different falls to the ground. The results showed that the injury was more likely to have been caused by direct impact, with an effect directed posterolaterally and laterally on the tibial plateau of the lower leg ; howeverTo determine ankle injury mechanisms in falls and traffic accidents, AFS utilised THUMS and FE to simulate falls from different heights and impacts from different directions. The results showed that falling causes a specific compression fracture of the distal tibia, whereas diaphyseal fractures of the tibia and fibula and ligament injuries caused by falling from lower heights or ankle inversion are not distinguishable from similar injury patterns caused by impact to the mid or upper leg. No obvious compression fracture of the distal tibia was caused by impact, whereas ligament injuries and avulsion fractures of the medial or lateral femoral condyles and diaphyseal fractures of the tibia and fibula were generated. Systematic studies would be helpful to analyse ankle injury circumstances and mechanisms encountered in forensic practice.et al. [Identifying whether a head injury was the consequence of a fall or a blow was a common question in forensic practice. The material properties of bones and brain, such as ultimate stress, ultimate strain, and elastic modulus, have a critical influence in the accuracy of computational simulations. However, there is a lack of research available on the properties of human body materials owing to the particularities of human tissue. Wang et al.  examinedRecently, numerical simulations are becoming a popular modeling method for real-world crash reconstruction and injury evaluation. However, the use of the multi-rigid-body dynamic method depends on accurate accident data, including impact position, braking distance, driving speed, etc. The more detailed the data are, the more realistic the simulation results will be. Besides, a limited number of simulations typically involves subjective evaluations of pre-impact parameters. AFS used a multi-mode image system to obtain accurate data of accident and a real case was analysed to verify the feasibility and effectiveness of the system .This case can be summarised as follows: A pedestrian was struck by vehicle when he was pushing his tricycle across the road. AFS combined unmanned aerial vehicle (UAV) photogrammetry, laser scanning and structured-light scanning to generate 3D models of the pedestrian, vehicles, and the scene. The 3D documentation of the vehicle body and incident scene saves permanent and raw material for the crash . FurtherBlood dispersal pattern analysis is a critical component of crime scene reconstruction. Blood drops are spherical when they travel through the air. When they strike a flat surface whose angle is less than 90° , elliptical bloodstains are formed. The morphology of the blood dispersal pattern can indicate impact angle and directionality of the blood drops, which can be used to determine the approximate location of the source. In the following case, 3D blood dispersal pattern analysis based on 3D scanning was performed.A 30-year-old woman was found lying unresponsive on the bed in the bedroom of an apartment . BloodstHuman body injury is common and an important part of forensic investigation and research, and the elucidation of the biomechanisms of injury is the key evidence in case characterisation for the division of responsibility, insurance claims, and case processing. Traditional forensic science mainly relied upon evidence such as characteristic injuries, field marks, and collision patterns to analyse injury mechanisms, but the injury mechanisms of complex injuries are generally difficult to determine. Based on research progress at home and abroad, forensic biomechanics has gradually overcome the limitations of empirical judgment, cadaver experiments, and animal experiments to a certain extent, and has the features of low cost, high efficiency, repeatability of different injury-causing conditions, rapid reconstruction ability of corresponding biomechanical responses, and therefore has a great advantage for the evaluation of injury mechanisms.Human tissues have properties such as anisotropy, viscoelasticity, and strain rate sensitivity, while the current biomechanical models have simplified mathematical constitutive and material properties, resulting in potential discrepancies between the calculated results and the actual mechanical response. Therefore, material property data from human tissue testing, especially from materials with high strain rates, are required. In addition, the failure criteria for different organs and tissues, which are important for the evaluation of injury risk, are not sufficiently developed and require improvement.Current validation of biomechanical models is insufficient. Current validation of the human biomechanical models is based on a series of classical cadaveric experimental data; however in forensic practice, the variability of injury-causing conditions is higher, the consequences of injury are more complex, and the validation of the existing models cannot completely cover the injuries addressed in forensic biomechanics. Therefore, we should validate forensic biomechanical models at multiple levels such as local, subsystem, and global scales; reconstruct forensic cases with clearly defined processes and conditions; further verify the validity of models using real-world data; and establish quantitative verification standards for simulation results and actual results to promote the continuous improvement of forensic biomechanical models, and thereby more accurately predict injury response and analyse injury mechanisms.The current accuracy of forensic biomechanics still relies upon the partial judgment of experts and the screening of loading conditions, which has good accuracy in explaining how an injury is caused but may produce false results in distinguishing the causal relationship between different injury-causing conditions, and actual injury for injury risks . TherefoHowever, owing to the uniqueness of the human anatomy, the complexity of biological materials, and the uncertainty of injury-causing circumstances, the direct application of biomechanical research to forensic practice is still accompanied by much uncertainty:Major research institutions around the world have invested a great deal of effort in forensic biomechanics research, and relying upon advances in biomechanics, the methods and models of forensic biomechanics have been improved. For Chinese research institutions, tremendous progress in forensic biomechanics modelling and practical applications have been achieved, making positive contributions to improve the probative and evidentiary value of forensic biomechanics.


Background: Diets have been a central component of lifestyle modification for decades. The Low-Carbohydrate Diet (LCD), originally conceived as a treatment strategy for intractable epilepsy (due to its association with ketogenesis), became popular in the 1970s and since then has risen to prominence as a weight loss strategy. Objective: To explore the efficacy, limitations and potential safety concerns of the LCD. Data Sources: We performed a narrative review, based on relevant articles written in English from a Pubmed search, using the terms ‘low carbohydrate diet and metabolic health’. Results: Evidence supports the efficacy of the LCD in the short-term (up to 6-months) for reduction in fat mass and remission of Type 2 Diabetes Mellitus (T2D). However, the longer-term efficacy of the LCD is disappointing, with diminishment of weight loss potential and metabolic benefits of the LCD beyond 6-months of its adoption. Furthermore, practical limitations of the LCD include the associated restriction of food choices that restrict the acceptability of the LCD for the individual, particularly over the longer term. There are also safety concerns of the LCD that stem from nutritional imbalances (with a relative excess of dietary fat and protein intake with associated dyslipidaemia and increased risk of insulin resistance and T2D development) and ketotic effects. Finally, the LCD often results in a reduction in dietary fibre intake, with potentially serious adverse consequences for overall health and the gut microbiota. Conclusions: Although widely adopted, the LCD usually has short-lived metabolic benefits, with limited efficacy and practicality over the longer term. Dietary modification needs tailoring to the individual, with careful a priori assessments of food preferences to ensure acceptability and adherence over the longer term, with avoidance of dietary imbalances and optimization of dietary fibre intake (primarily from plant-based fruit and vegetables), and with a posteriori assessments of the highly individual responses to the LCD. Finally, we need to change our view of diets from simply an excipient for weight loss to an essential component of a healthy lifestyle. The global obesity epidemic poses a major threat to our health, with much associated chronic ill health that includes >50 separate obesity-related co-morbidities ,2. CardiTraditionally, there is division of obesity management into three distinct phases: lifestyle, pharmacotherapy and bariatric surgery. Currently, bariatric surgery provides our best evidence for long-term effective weight loss in obesity . AlthougLifestyle is an umbrella term that incorporates all aspects of healthy behaviours including sleep quality and sufficiency, physical activity, smoking cessation and the optimization of mental and emotional health. Attention to diet forms a major component of a healthy lifestyle. There are a myriad of diets available, based on multiple variables. These include the combinations of macronutrients, the duration and timing of meals, the duration and periodicity of fasting periods, chewing time, the speed of eating, the duration of the diet, the types of cooking techniques and even the emulation of previous eras such as the ‘Paleolithic Diet’. Amongst all available diets though, the Low-Carbohydrate Diet (LCD) features prominently. The LCD, conceived a century ago as a means of inducing ketonaemia as a treatment strategy for intractable epilepsy , has onlWe performed a narrative review of the current literature. We used Pubmed for this purpose. The search terms included ‘Low carbohydrate diet’ in combination with the following: ‘metabolic health, definition, physical activity, limitations, nutrition, ketosis, hyperuricaemia, inflammation and microbiota’. We chose published studies for inclusion in our narrative review based on their relative size, novelty and perceived clinical relevance as assessed by the authors; and related review articles, including systematic reviews and meta-analyses. We only considered articles written in English, with no restrictions on the date of publication.The definition of the LCD varies between studies, and includes a diet that contains <130 g of carbohydrate per day  . Howeverthe great charms of the system are that you are never hungry and its effects are palpable within a week of trial and creates a natural stimulus to persevere a few weeks more”. The original LCD (with relatively high dietary intakes of fat and protein) was conceived 100 years ago in 1921 as a means of inducing ketogenesis, as a non-pharmacological treatment option for intractable childhood epilepsy ) in elite endurance athletes, in contrast to diets that provide high-carbohydrate availability, training with the LCD impaired athletic performance despite improved peak aerobic capacity . HoweverThe longer-term metabolic and weight-losing efficacy of the LCD, its acceptability to the individual and associated limitations are important considerations. However, an even greater concern relates to the potential safety concerns of the LCD that originate from multiple sources . There is controversy in the literature regarding the health effects of a high-protein diet. Over the longer term, there are reported unfavourable metabolic effects of a diet that is proportionately high in protein, including association with dysglycaemia ,54. In aHyperuricaemia and Inflammatory Effects: A further theoretical risk of the LCD includes hyperuricaemia (with associated gouty arthritis and uric acid nephrolithiasis) from excessive conversion of purines from animal proteins following adoption of the LCD (with relatively high dietary intake of proteins) ,61. Howeinsoluble and non-fermentable cereal fibres (derived from oat or wheat extracts and whole grain products) rather than soluble and highly fermentable types of dietary fibre, associates with reduced risk for the development of T2D and improved insulin sensitivity [Mitigation of some of the nutritional and metabolic problems associated with the LCD could occur through the concomitant optimization of dietary fibre intake. Our own group showed that the ingestion of sitivity ,69,70. Wsitivity . The comsitivity ,73. Furtsitivity ,75,76. FAs outlined, the main safety concerns regarding adoption of the LCD relate to their nutritional and ketotic effects. Furthermore, epidemiological studies consistently report increased mortality with the LCD . Whilst Finally, although this goes well beyond the scope of our concise review, we need to consider the potential for the indirect effects of gut dysbiosis that may stem from adoption of the LCD, with the inherent high intake of fats and protein, typically found in animal-based foods, and relative paucity of carbohydrate- and fibre-laden plant-based foods . Given tDespite decades of research, it is remarkable how little we actually know about the human diet. It is probably fair to say that most of us think we know more than we actually do. There are many reasons why dietary insights remain elusive. These include the inherent difficulties of studying diets in isolation, with every diet containing a complex array of macronutrients and many other variables. There is also the problem of accuracy, with most of us under-estimating our daily caloric intake and problems of self-recall that plague many dietary studies. There are cultural factors, with specific dietary preferences and norms widely variable across global populations. Finally, there are human variables from our own unique genetic and physiological make-up, and the complex array of microbiota within our gut, unique to each individual. Faced with this complex and highly variable set of factors, it is hardly surprising that we have limited knowledge and insights into the optimization of our diets for health. Although specific dietary advice exists for certain groups, the vast majority of us are encouraged to follow the standardized government advice regarding a healthy diet, with recommended daily caloric intakes simplified based on sex. However, a more refined approach is required, one that is tailored to the individual, and based on much more sophisticated inputs than sex. As alluded to, the gut microbiota is hugely relevant to our handling of macronutrients, and a future scenario may incorporate individualized gut faecal profiles that inform specific dietary requirements . GeneticUltimately, our diet should form an essential component of a healthy lifestyle. From a nutritional perspective, it is important that any dietary intervention contains a proper balance of healthy fats, proteins, carbohydrates, fibre, minerals and vitamins . Due to How can we proceed in the future to optimize our diets for maximal health benefits? There is clearly a need for more large-scale, prospective multi-centre trials on the effects of the LCD. Despite the publication of >100 separate LCD and LFD randomized controlled trials, our understanding of the benefits of the LCD remains limited, at least in part due to heterogeneity amongst the design of different studies. We suggest a bold initiative to explore major dietary approaches such as the LCD on the same scale as research in therapeutics, with a 1–5 year duration and inclusion of >5000 participants. Such a study design would enable the exploration of major primary assumptions (such as remission/prevention of T2D and CVD outcomes), and many secondary assumptions . With antecedents of the PREDIMED (Prevenciόn con Dieta Mediterránea) study on the benefits of the Mediterranean diet  and the As outlined earlier, an individualized and algorithmized approach to diets seems sensible. We also need to change our societal mind-set regarding the purpose of dietary change. Rather than diets perceived simply as a means to lose weight, we need to change our perspective to one in which diets are considered as an essential component of healthy lifestyle, which if followed correctly with other lifestyle measures, will improve our future health outlook, and may even optimize our body weight. Above all, for longer-term adherence, it is essential that whatever the chosen lifestyle strategy (including dietary change), this is practical, feasible and importantly enjoyable for the individual engaged in such behaviour changes. Without enjoyment, any long-term change is destined to fail. Perhaps one reason why dietary and lifestyle changes are so disappointing over the longer term is that the available options are too rigid, and as healthcare professionals, we do not invest enough time in ascertaining practicality, feasibility and enjoyability of suggested behaviour changes for each individual prior to making such recommendations. With such a priori assessments, we can tailor our approach to the individual, and any recommended lifestyle change, dietary or otherwise, will have a greater chance of longer-term success. In addition to rigidity, perhaps our traditional approach to diets is also too prescriptive. The available evidence shows that weight loss occurs following a reduction in daily caloric intake, regardless of the macronutrient origin of those calories, although the magnitude of weight loss varies according to the type of macronutrient, and the effects on diet-induced thermogenesis . TherefoTo conclude, evidence reveals metabolic efficacy of the LCD at least during the short-term. Unfortunately, there are substantial limitations to the LCD that restrict its metabolic efficacy over the longer-term, coupled with potential safety concerns. Compared with the LCD, caloric restriction offers a greater selection of food (including plant- and fibre-based) options with fewer safety concerns . Perhaps even relatively modest caloric restriction provides a practical, feasible and enjoyable dietary alternative to the LCD, accomplishable over the longer-term and offering hope for the future.


An increasing number of systematic reviews/meta-analyses (SRs/MAs) of clinical trials have begun to investigate the effects of traditional Chinese medicine (TCM) nursing in patients with stroke. To systematically appraise and synthesize these results, we conducted an overview of SRs/MAs.  Eight databases from their inception to April 2020 were searched to include all SRs/MAs on TCM nursing for stroke. Methodological quality assessment was performed using Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR-2) and evidence quality assessment was performed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE).  Eleven SRs/MAs regarding TCM nursing for stroke were included. The assessments with AMSTAR-2 indicated that the methodological quality of all included SRs/MAs was critically low. According to the evaluation results of GRADE, 10 (40%) outcomes were rated as critically low-quality evidence, 7 (28%) low-quality evidence, and 8 (32%) moderate-quality evidence. Descriptive analysis results showed that TCM nursing was effective for stroke.  All included SRs/MAs suggested positive findings of TCM nursing for stroke, but the credibility of the results is limited. Studies with methodologically rigorous and adequately powered are still needed in this field. Stroke is the second leading cause of death and third leading source of disability worldwide . It has Traditional Chinese medicine (TCM) nursing was established under the guidance of the basic theory of TCM . AccordiThe methodology of this overview was followed the guidelines stated in the Cochrane handbook and the method of high-quality overviews –11. The To be included, SRs/MAs had to meet the following criteria: (1) the definition of TCM nursing was guided by the Routine and Technical Operation Regulations of Nursing Care in TCM . EighteeEight databases , Wanfang Database, Chongqing VIP, and Chinese Biomedical Database) were searched from their inception to April 2020. Search keywords were TCM nursing, stroke, systematic review, and meta-analysis. After removing duplicates of the retrieved citations, two independent reviewers screened the titles and abstracts of potentially eligible articles to determine whether the articles met the eligibility criteria. After preliminary screening, full-text manuscripts of potential articles were retrieved and reviewed in detail according to eligibility criteria.Data extractions from included reviews were extracted by two independent reviewers following the standardized data extraction forms. Study characteristics , details of the intervention , methodological quality assessment tools, outcomes, and summery results were also extracted.The methodology quality of the included SRs/MAs was independently evaluated by two reviews using the Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR-2) . It has The evidence quality of the included SRs/MAs was independently evaluated by two reviews using the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) system . FactorsA total of 167 articles were identified and 31 duplicates were excluded. Subsequently, 116 records were excluded on the basis of their titles and abstracts. The remaining 20 articles were retrieved in full-text format for further assessment, and a further 9 articles were excluded. Finally, 11 –24 articThe descriptive characteristics of the included SRs/MAs are presented in n = 6, 100%)), item 4 ), item 7 ), and item 15 ). The breakdown of the AMSTAR-2 assessment is presented in After evaluation of the methodological quality by the AMSTAR-2 tool, all included SRs/MAs were rated to be of critically low quality. The critical items that were most frequently lacking were item 2 , 7 (28%), and 10 (40%) were rated to be of moderate, low, and critically low quality, respectively. The key factors affecting the evidence quality included the study limitations within the original RCTs, inconsistency, publication bias, and imprecision. Details of the GRADE evaluation are shown in One review  analyzedTwo reviews , 19 analTwo reviews , 23 analTwo reviews , 20 analOne review  analyzedThree reviews , 22, 24 Eleven SRs/MAs on TCM nursing for stroke were included, published from 2015 to 2020. All studies were published within the past five years, meaning that TCM nursing has become a new research concern. This overview included 25 outcome measures, almost all of which reached positive conclusions. Although most of the included SRs/MAs showed that TCM nursing was beneficial for stroke, the authors did not want to draw firm conclusions because of the small size or the low methodological quality of the included trails. In addition, based on the evaluation results of AMSTAR-2 and GRADE, the methodological quality and the evidence quality of the included SRs/MAs are not satisfactory, indicating that the results of SRs/MAs may differ significantly from the real situation. Therefore, high-quality and large simple size studies are still needed to determine precisely the efficacy and safety of these stroke interventions.The results of AMSTAR-2 evaluation show that each SRs/MAs has different deficiencies in terms of design, registration, data extraction, and analysis. All SRs/MAs did not include a preliminary design protocol, which may result in greater adjustments to the research process than expected, increase the risk of bias, and affect the rigor of SR/MA. Only two SRs/MAs provided specific search strategy, which may result in publication bias and affect the conclusion's reliability. All SRs/MAs did not provide a complete list of potential studies, which may affect the reliability of the results. The list of excluded articles provided could more strongly prove the rigor of the literature screening process. Only four SRs/MAs reported funding resources and stated the conflicts of interests, which may increase study reporting bias. Two SRs/MAs did not take published bias into account when the authors explain or discuss the results of the study and explain their possible sources, which may affect the authenticity of the final results. The above defects are the main reason for the very low quality of the included SR/MA methodology.The results of GRADE evaluation indicate that the current quality of evidence is unsatisfactory. The key factors affecting the evidence quality included limitations, inconsistency, imprecision, and the possibility of publication bias. These evidence quality defects suggest that the conclusions of the SRs/MAs may be different from the true results and therefore do not provide a scientific basis for clinicians. The limitations of the original RCTs are the main factor in the decrease of the quality of all evidence. Of these original RCTs, most of them only mentioned randomization but did not describe the randomization method; most did not conceal the allocation; only a few mentioned blinding, and most of these used only single blinding. These common deficiencies limited the quality of the original RCTs and the evidence quality of the SRs/MAs.TCM has thousands of years' history in China. Nursing science characterized by TCM, named TCM nursing, is a significant component of complementary and alternative medicine. Different from ordinary physiotherapy, TCM nursing shares the same theory and philosophy as TCM, and the advantages of TCM nursing include health education based on theories and techniques of TCM . In ChinEvidence is the top priority for a smart medical decision. The concept of evidence-based medicine changes nurses' practice from experience-based to evidence-based, guiding nurses to retrieve and make use of the best evidence available. This concept would be beneficial in the literature review of TCM nursing research, health education, and standardization of TCM nursing techniques, and may solve the dilemma faced by TCM nursing to a certain extent . As sourThis study has certain limitations to be acknowledged. First, the stroke status and time post onset of the enrolled patients were not completely consistent, which may exaggerate or decrease the efficacy of TCM nursing and affect the robustness of the study conclusion. The prognosis of patients with different stroke status and time after onset is significantly different. Second, the protocols of TCM nursing are also diverse, including differences in TCM nursing techniques, stimulation methods, treatment duration, and number of treatments, which may result in a source of heterogeneity for the included reviews. Third, measurement scales used in the enrolled RCTs included SPBB, BBS, SAS, SDS, WST, FMA, etc., all of which were subjective clinical assessment tools based on the observation of the assessors. In addition, the most commonly used measure to assess the efficacy of TCM nursing for stroke was effective rate; however, it was not internationally recognized. Thus, the use of these indicators in the assessment of treatment effects may be inaccurate. Fourth, although objective criteria are established based on the evaluation of relevant literature, there may still be some subjectivity in the evaluation process. Finally, based on the current results, this study cannot draw firm conclusions for the use of TCM nursing for stroke. Further rigorous, comprehensive SRs/MAs and RCTs that adhere to the guidelines are required to provide robust evidence for definitive conclusions.All included SRs/MAs suggested positive findings of TCM nursing for stroke, but the credibility of the results is limited owing to the summary evidence of this overview. The methodological quality and evidence quality of the included studies were generally low. The practice of using the widely accepted tools like AMSTAR-2 and GRADE for designing, reporting, and assessing of SRs/MAs needs to be encouraged and advocated, hereby providing more convincing evidence based on their findings.