Authentication and quality control of Uapaca heudelotii Baill. - An investigation of pharmacognostic, phytochemical and physicochemical properties of its leaves and stem bark

Uapaca heudelotii Baill. is well known in various African cultures for its application in the treatment of infections and inflammatory conditions. This study was focused on providing standard identification parameters for authentication and quality assurance of U. heudelotii through morphological observations, screening of phytochemical constituents, fluorescence, spectroscopic and physicochemical analysis. U. heudelotii leaves are simple, elliptic and arranged in whorls. The bark is greyish-brown with longitudinal striations on the outer surface and pale red on the inner surface. Leaf lamina microscopy displayed anticlinal polygonal straight-walled epidermal cells, with anisocytic stomata found only on the abaxial surface. Leaf surface constants were determined. Microscopy of powdered leaves and barks revealed the presence of epidermal cells, starch grains, calcium oxalate, sclereids and pitted vessels. Alkaloids, flavonoids, coumarins, saponins, triterpenoids, phytosterols and tannins were identified in both stem bark and leaves. The total phenolic content for the leaf and bark were 219.2 ± 10.013 and 153.9 ± 1.602 mg/g gallic acid equivalent respectively. The total ?avonoid contents were recorded as 1036 ± 33.37 and 310.2 ± 79.00 mg/g quercetin equivalent for the leaf and bark respectively. The total ash for the leaf and bark was 6.41 ± 0.208 and 5.01 ±0.258 respectively. The pH values for the aqueous and alcoholic extracts were slightly acidic (3-5). In elemental analysis, lead (Pb) was detected within the acceptable limit (0.0019-0.0025 mg/kg). In conclusion, the current results have provided standard parameters for the correct identification and quality assessment of U. heudelotii

Physical Aspects of Cell Culture Substrates: Topography, Roughness, and Elasticity

The cellular environment impacts a myriad of cellular functions by providing signals that can modulate cell phenotype and function. Physical cues such as topography, roughness, gradients, and elasticity are of particular importance. Thus, synthetic substrates can be potentially useful tools for exploring the influence of the aforementioned physical properties on cellular function. Many micro‐ and nanofabrication processes have been employed to control substrate characteristics in both 2D and 3D environments. This review highlights strategies for modulating the physical properties of surfaces, the influence of these changes on cell responses, and the promise and limitations of these surfaces in in‐vitro settings. While both hard and soft materials are discussed, emphasis is placed on soft substrates. Moreover, methods for creating synthetic substrates for cell studies, substrate properties, and impact of substrate properties on cell behavior are the main focus of this review. The cellular environment plays a significant role in cell phenotype and function. As such, physical properties of cell culture substrates including topography, roughness, and elasticity may be utilized to investigate the influence of these physical cues on the cellular response. In this review, strategies for modulating the physical properties of surfaces, the influence of these changes on cell responses, and the promise and limitations of these surfaces in in‐vitro settings are highlighted, with a particular emphasis on elastic substrates.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90132/1/336_ftp.pd

Insect pathogens as biological control agents: back to the future

The development and use of entomopathogens as classical, conservation and augmentative biological control agents have included a number of successes and some setbacks in the past 15 years. In this forum paper we present current information on development, use and future directions of insect-specific viruses, bacteria, fungi and nematodes as components of integrated pest management strategies for control of arthropod pests of crops, forests, urban habitats, and insects of medical and veterinary importance. Insect pathogenic viruses are a fruitful source of MCAs, particularly for the control of lepidopteran pests. Most research is focused on the baculoviruses, important pathogens of some globally important pests for which control has become difficult due to either pesticide resistance or pressure to reduce pesticide residues. Baculoviruses are accepted as safe, readily mass produced, highly pathogenic and easily formulated and applied control agents. New baculovirus products are appearing in many countries and gaining an increased market share. However, the absence of a practical in vitro mass production system, generally higher production costs, limited post application persistence, slow rate of kill and high host specificity currently contribute to restricted use in pest control. Overcoming these limitations are key research areas for which progress could open up use of insect viruses to much larger markets. A small number of entomopathogenic bacteria have been commercially developed for control of insect pests. These include several Bacillus thuringiensis sub-species, Lysinibacillus (Bacillus) sphaericus, Paenibacillus spp. and Serratia entomophila. B. thuringiensis sub-species kurstaki is the most widely used for control of pest insects of crops and forests, and B. thuringiensis sub-species israelensis and L. sphaericus are the primary pathogens used for medically important pests including dipteran vectors,. These pathogens combine the advantages of chemical pesticides and microbial control agents (MCAs): they are fast acting, easy to produce at a relatively low cost, easy to formulate, have a long shelf life and allow delivery using conventional application equipment and systemics (i.e. in transgenic plants). Unlike broad spectrum chemical pesticides, B. thuringiensis toxins are selective and negative environmental impact is very limited. Of the several commercially produced MCAs, B. thuringiensis (Bt) has more than 50% of market share. Extensive research, particularly on the molecular mode of action of Bt toxins, has been conducted over the past two decades. The Bt genes used in insect-resistant transgenic crops belong to the Cry and vegetative insecticidal protein families of toxins. Bt has been highly efficacious in pest management of corn and cotton, drastically reducing the amount of broad spectrum chemical insecticides used while being safe for consumers and non-target organisms. Despite successes, the adoption of Bt crops has not been without controversy. Although there is a lack of scientific evidence regarding their detrimental effects, this controversy has created the widespread perception in some quarters that Bt crops are dangerous for the environment. In addition to discovery of more efficacious isolates and toxins, an increase in the use of Bt products and transgenes will rely on innovations in formulation, better delivery systems and ultimately, wider public acceptance of transgenic plants expressing insect-specific Bt toxins. Fungi are ubiquitous natural entomopathogens that often cause epizootics in host insects and possess many desirable traits that favor their development as MCAs. Presently, commercialized microbial pesticides based on entomopathogenic fungi largely occupy niche markets. A variety of molecular tools and technologies have recently allowed reclassification of numerous species based on phylogeny, as well as matching anamorphs (asexual forms) and teleomorphs (sexual forms) of several entomopathogenic taxa in the Phylum Ascomycota. Although these fungi have been traditionally regarded exclusively as pathogens of arthropods, recent studies have demonstrated that they occupy a great diversity of ecological niches. Entomopathogenic fungi are now known to be plant endophytes, plant disease antagonists, rhizosphere colonizers, and plant growth promoters. These newly understood attributes provide possibilities to use fungi in multiple roles. In addition to arthropod pest control, some fungal species could simultaneously suppress plant pathogens and plant parasitic nematodes as well as promote plant growth. A greater understanding of fungal ecology is needed to define their roles in nature and evaluate their limitations in biological control. More efficient mass production, formulation and delivery systems must be devised to supply an ever increasing market. More testing under field conditions is required to identify effects of biotic and abiotic factors on efficacy and persistence. Lastly, greater attention must be paid to their use within integrated pest management programs; in particular, strategies that incorporate fungi in combination with arthropod predators and parasitoids need to be defined to ensure compatibility and maximize efficacy. Entomopathogenic nematodes (EPNs) in the genera Steinernema and Heterorhabditis are potent MCAs. Substantial progress in research and application of EPNs has been made in the past decade. The number of target pests shown to be susceptible to EPNs has continued to increase. Advancements in this regard primarily have been made in soil habitats where EPNs are shielded from environmental extremes, but progress has also been made in use of nematodes in above-ground habitats owing to the development of improved protective formulations. Progress has also resulted from advancements in nematode production technology using both in vivo and in vitro systems; novel application methods such as distribution of infected host cadavers; and nematode strain improvement via enhancement and stabilization of beneficial traits. Innovative research has also yielded insights into the fundamentals of EPN biology including major advances in genomics, nematode-bacterial symbiont interactions, ecological relationships, and foraging behavior. Additional research is needed to leverage these basic findings toward direct improvements in microbial control

Road pricing: a solution to Ghana's traffic congestion

Congestion in major cities around the world calls for the proper management of space vehicles occupy on road networks. The paper develops models that combine the density of car usage in an area, space occupies by vehicles and the damage they cause to roads in the payment of vehicle registration, renewal, and towing rates. The paper confirms that larger vehicles cause greater congestion on roads by virtue of the space they occupy and causes greater damage to the road, as compared to small-sized vehicles. Vehicles should pay road rates commensurate with the density of vehicles, the space they occupy and the damage they cause to the road. From our models, Mercedes-Benz and Toyota, Camry are undercharged across all the offices in the country, except for Tema and Bolga, which charges 120 and 80 Ghana cedis respectively above the 60 Ghana cedis national charge. For new car registration fees, we found that the current charge is higher for New Audi A1 Sportback 2019 except at theTema registration office, which charges more than 20 Ghana cedi above the national charge of 100 Ghana cedis. The paper also provides models for costing the removal of vehicles that park at unauthorized places as well as broken-down vehicles on highways. The paper suggests that this method of road user rates payment, aside being a good source of revenue for governments would encourage people to patronize public transport. This will ease road congestion, road rage as well as other unwanted road behaviors, particularly around and within city centres

Corrigendum: The Ghanaian Flora as a Potential Source of Anthelmintic and Anti-Schistosomal Agents

Parasitic infections including schistosomiasis and soil transmitted helminthiasis are the most commonly encountered Neglected Tropical Diseases (NTDs) in the world. These diseases remain a major public health concern affecting millions of people especially those living in poor regions where access to effective conventional health care is a challenge. Interventions to control these infections in endemic areas have not been successful due to the high cost of drugs, limited availability as well as inequity of access to preventive chemotherapies. Another problem is the development resistance to the limited number of recommended medications due to their intensive use in both human and live-stock. There is an increasing awareness of the potential of natural products as chemotherapeutic agents to combat parasitic infections. Natural products may offer an unlimited source of chemically diverse drug molecules which may be safe, efficient, less toxic, less expensive and readily available for use especially in low-income countries. The Ghanaian flora provides such a ready source for new therapeutic interventions for the local population. Several researches have provided evidence of the anti-parasitic activity of Ghanaian medicinal plants. This chapter provides a review with special focus on medicinal plants collected from Ghana with anthelmintic and anti-schistosomal activity. Evidence of pharmacological activities of crude extracts, fractions and bioactive phytoconstituents as well as possible mechanisms of action where investigated are discussed