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There is considerable interest in the plant family Amaryllidaceae for its biologically-active isoquinoline alkaloid principles. Some of these (such as galanthamine and narciclasine) have demonstrated their applicability in the clinical arena, particularly as cancer and motorneuron disease therapeutics. While synthetic organic chemistry affords ideal opportunities for drug development with such targets, the phytochemical approach is considered a somewhat more amenable option. In this regard, southern Africa has garnered widespread attention due to the abundance of Amaryllidaceae plants in its territory. Crinum, Ammocharis, Amaryllis, Cyrtanthus and Brunsvigia are genera of the family that are likewise well-represented in southern Africa. Up to 2012, thirty members from these genera were examined for their chemical and biological properties, culminating with the identification of nearly one-hundred alkaloid entities several of which exhibited notable biological activities. The present effort covers studies since 2013 that have been undertaken on the title genera in regards to their chemical and biological characteristics. Close to ninety alkaloids and twenty-five non-alkaloid entities were described during this time-frame from fifteen representative species. Biological studies included cholinesterase inhibiton, cytotoxicity, antidiabetes and antihypertensive effects, herbicidal, insecticidal and plant growth regulatory effects, as well as anti-inflammatory, antioxidant and antiplasmodial effects. The structural variety of the compounds isolated in cases allowed for structure-activity probes to be made in some of the assays. There were also studies carried out to establish the molecular basis to these activities, notably in the area of molecular cancer chemotherapeutics.

Understory plants are often inadequately represented or neglected within analyses of forest ecosystem productivity. Further, the potential impacts of the biological factors of age class and growth form on carbon cycling physiology, and how it may vary across the growing season and amongst species of different native/non-native status, have not been thoroughly considered. Our study examines photosynthesis and associated physical leaf traits in two understory woody species, Rhamnus cathartica, introduced and invasive in North America, and Prunus serotina, a common subcanopy species native to North America. We estimated leaf-level photosynthesis as measured through light and carbon dioxide response curves, dark-adapted chlorophyll fluorescence and leaf traits (leaf mass per area and stomatal density) for each combination of species and age class at plots in the understory of a temperate deciduous research forest in the US Upper Midwest at two time points during the growing season, late spring (late May) and mid-summer (mid-July). Carbon assimilation rates from light response curves (Asat, A400) and fluorescence capacity estimate Fv/Fm all increased between the two measurement points in both species and age class. Estimates of carbon reaction capacity (Vcmax and Jmax) exhibited a different directional response to seasonal development, declining in seedlings of both species and P. serotina trees (~8–37 % reduction in Vcmax, ~9–34 % reduction in Jmax), though increased in trees of R. cathartica (+24 % in Vcmax, +9 % in Jmax). Divergent responses in photosynthetic parameters amongst these factors may be explained by species differences in leaf mass per area and stomatal density, which together are likely influenced by both growth form, canopy position and ontogeny. Overall, we believe our findings suggest complex, varied influences on photosynthesis that indicate environmental and biological plasticity which may contribute to the historic and continued expansion of R. cathartica in the US Upper Midwest region.

This research effort examined the current advanced battery requirement (baseline) and projects anticipated battery requirements for the operating force in 2035 and 2045. The research is conducted using a mission engineering perspective to determine the battery requirements. The analysis includes battery chemistry, energy density, charge/discharge rate, safety concerns, and the like, of the battery. In this research the following questions are answered: What is the current advanced battery requirement (baseline)? What is the projection for batteries required by the operating force by 2035? What is the projection for batteries required by the operating force by 2045? Upon completion of the research, the team was able to definitively determine that there will be a role for Li-ion batteries within the fleet of Navy vessels. That role will, however, be limited to running specific subsystems or equipment and will not replace the ship generators. This will remain true until the energy density of battery technology even begins to approach that of petrochemicals, which we believe is many years away if possible. Outstanding Thesis Civilian, Department of the Army Civilian, Department of the Army Civilian, Department of the Army Civilian, Department of the Army Civilian, Department of the Army Approved for public release. Distribution is unlimited.

Stimulated by the promising results seen for its phenanthridones in clinical trials, interest in the Amaryllidaceae as a potential source of anticancer drugs has intensified in recent years. As such, over three hundred isoquinoline principles from its various alkaloid groups have to date been screened against a large number of cancer cell lines. Whilst significant effort has been diverted towards studies of lycorine and its congeners, the closely-allied homolycorine alkaloids of this plant family have largely been overlooked. These compounds have often been used as supporting acts to bolster the diversity of structures in cytotoxicity studies of the more recognized phenanthridone, lycorane and crinane alkaloids of the Amaryllidaceae. This notwithstanding, a substantial amount of information has surfaced over the past several years on such effects for the homolycorine alkaloids. This review takes a detailed look at the cytotoxic effects manifested by over forty of these alkaloids against around sixty cell lines, which may be classified into eighteen different types of cancers. In this regard, good activities were detected for some constituents (such as lycorenine and hippeastrine) against various hepatic and prostate cancers. The structural features which support and fortify the efficacy of the homolycorine alkaloid cytotoxic pharmacophore are also considered. These include the ways in which the innate ring systems are appended as well as the size, geometry and electronics of the attendant substituents. In addition, the various mechanisms used to rationalize the cytotoxic responses are described notably, interaction with DNA, apoptosis induction, protection from tumor invasion, efflux pump perturbation and topoisomerase inhibition.

From camptothecin to vinblastine, plant alkaloids continue to capture the imagination of scientists as a valuable source of anticancer drugs. Given that they are also amongst the most common secondary metabolites encountered in plants, the number of alkaloid entities subjected to cytotoxicity evaluations now runs into several thousands. Interest in the plant family Amaryllidaceae has been persistent owing to the potent cytotoxic activities of several of its isoquinoline alkaloid principles. This survey is an indepth account of such properties discernible for tazettine alkaloids belonging to the minor alkaloid groups of the Amaryllidaceae. Eleven of such compounds have up to now been screened against around 50 cancer cell lines which may be classified into nearly 20 different types of cancers. Although the activities in most instances were moderate to mild, notable responses were observed against some leukemia, adenocarcinoma, lymphoma and glioblastoma cell lines. In fact, pretazettine (ED50 0.3 μg/mL) was amongst the most potent of all Amaryllidaceae alkaloids screened against the human Molt4 T-lymphoma cell line. To most accounts, the parent compounds (such as tazettine and pretazettine) with their distinct ring systems and substitution patterns exhibit the best activities, offering little space for structural adjustments via semi-synthetic operations. Several avenues have been probed in attempts to elucidate the mechanisms by which tazettine alkaloids manifest their cytotoxic effects including, inhibition of protein synthesis, apoptosis and efflux pump interactions, the first of which to date offers the most profound insights.

Background In spite of the significant progress in modern medicine, viruses continue to be a formidable challenge to human health. The use of plants for the remediation of viral-borne diseases stretches back to the very dawn of mankind. Among bulbous plants, the Amaryllidaceae is one of the most popular families exploited in the traditional remediation of infectious diseases. Methods This account details the findings from a literature search carried out on the antiviral properties of the Amaryllidaceae. The keyword engaged in the search was “antiviral” in combination with the words “Amaryllidaceae,” “Amaryllidaceae specie,” and “Amaryllidaceae alkaloid.” Results Thirty-six taxa from 13 countries, notably in Africa and parts of Asia, have been cited as traditional remedies for viral diseases. Alcoholic bulb extracts of 18 species were evaluated against 23 different pathogens from 13 viral families. A wide range of activities was observed, with the whole-plant methanol extract of Zephyranthes candida seen to be the most striking (IC50 0.0019 µg/mL against poliovirus). The active principles in the main were isoquinoline alkaloids, of which lycorine impressed against the Avian influenza virus (strain H5N1). The mechanisms underlying the antiviral effects were seen to be related to the inhibition of DNA, RNA, and protein synthesis as well as inhibitory effects toward reverse transcriptase and protease enzymes. Conclusion Amaryllidaceae provides a richly diverse platform for antiviral drug research. Such endeavors have been fortified by the significant amounts of information emerging from indigenous knowledge systems. Ongoing studies will continue to target the active entities, particularly from taxa with verifiable ethnomedicinal backgrounds.

Viral-borne diseases are amongst the oldest diseases known to mankind. They are responsible for some of the most ravaging effects wrought on human health and well-being. The use of plants against these ailments is entrenched in both traditional and secular medicine around the globe. Their natural abundance and chemical diversity have also boosted their appeal in drug discovery.The plant family Amaryllidaceae is distinguished for its alkaloid principles, some of which are of considerable interest in the clinical arena. This account is the outcome of a literature review undertaken to establish the applicability of these substances as antiviral agents.The survey utilized the search engines Google Scholar, PubMed, SciFinder, Scopus and Web of Science engaging the word 'antiviral' in conjunction with 'Amaryllidaceae' and 'Amaryllidaceae alkaloid'. The search returned over five hundred hits, of which around eighty were of relevance to the theme of the text.Over eighty isoquinoline alkaloids have been screened against nearly fifty pathogens from fourteen viral families, the majority of which were RNA viruses. Potent activities were reported in some instances, such as that of trans-dihydronarciclasine against Yellow fever virus (ICThe Amaryllidaceae offers a viable platform for plant-based antiviral drug discovery. Its cause is strengthened not only by its wide proliferation and exploitation of its members in alternative forms of medicine, but also by its rich chemical diversity which has already spawned useful antiviral drug leads.

There are subtle mechanisms at work in nature to maintain a balance in the interactions between plants and animals. The production of secondary metabolites is one of the key strategies utilized by plants to minimize their over-exploitation. The ‘lily borer’ moth Brithys crini poses a considerable challenge to Amaryllidaceae plants owing to the devestation it can cause during the larval stage of its development. This, despite the fact that the Amaryllidaceae is richly endowed with an assortment of isoquinoline alkaloid constituents which exhibit a diverse array of biological properties, particularly cytotoxicity-related effects. In this study, laboratory-maintained larvae of B. crini were periodically fed fresh leaves of Crinum moorei during the September to November infestation period in Pietermaritzburg, South Africa. Solvent extracts of the plant leaves, moth larvae and larvae excrement material were then prepared and subjected to HPLC and LC–MS analyses. The presence of several alkaloids, including cherylline and ambelline, in all three extracts was ratified via HR-MS and NMR analyses. The identification of ambelline is noteworthy since it has not been reported in previous studies of C. moorei. Toxicity related criteria are also considered based on the present detection of alkaloids in B. crini larvae material, as well as precedence for their association with other known insect predators of the Amaryllidaceae.

Increasingly, undergraduate institutions are incorporating original research into the curriculum as a matter of best practice. However, while the practice of science has grown more collaborative, undergraduate research has remained largely confined to single-institution studies. Incorporating long-term, distributed research projects into the undergraduate research experience can better prepare students to interpret and engage in science of the future. The Decomposition in Aquatic and Terrestrial Invaded Systems (DATIS) project within the Ecological Research as Education Network (EREN) offers a good model for examining how to minimize challenges and maximize opportunities associated with classroom use of long-term, collaborative research projects. Eleven key challenges are identified, and practical solutions are provided for each. By modeling this scientific approach in primarily undergraduate institutions, we are preparing graduates who will have the tools and knowledge to work collaboratively and create their own distributed research networks. Our goal is that the decomposition project we describe here can inform and inspire others seeking to engage in research at the undergraduate level, either as potential research coordinators or as collaborators in an existing network.

Malaria is responsible for majority of the morbidity and mortality statistics reflected by tropical diseases. Whilst effectively managed in most parts of the globe, it remains a scourge on the African continent where most cases of the disease are diagnosed annually. Plants have played a leading role as a source of malarial drugs which continue to dominate the clinical landscape today. Most if not all of these discoveries have as their basis evidence which can be traced back to traditional medicine. There is likewise precedence for the use of Amaryllidaceae plants in traditional medicinal approaches towards malaria. The chief phytochemical principles of the Amaryllidaceae are its isoquinoline alkaloids which are responsible for its diverse biological properties. These alkaloids may be divided into major and minor groups based on their distinguishing structural features as well as their natural abundance and distribution in the family. Whilst much has been written about the biological and chemical properties of the major alkaloid groups of the Amaryllidaceae, relatively little is known or understood about its minor alkaloid groups. This review focuses on the antiplasmodial activities described in the literature for the minor alkaloid group members of the Amaryllidaceae against various strains of the malarial pathogen Plasmodium falciparum . Three database platforms (Google Scholar, SciFinder and Scopus) were utilized for the literature search. Articles were accessed from journals licensed to the University of KwaZulu-Natal, or directly via the respective corresponding authors. Also considered are structural elements of these alkaloids which may be used to explain such activities as well as to provide a foundation in attempts to modulate activities. In addition, evidence is provided on the molecular basis to these effects which could guide efforts in drug discovery.

Cancer is a leading cause of death worldwide. This, in spite of the tremendous gains made in cancer chemotherapies over the past several decades. The identification and development of new targets with greater structural diversities and better potencies are at the forefront of drug discovery endeavors across disciplines. Plants have afforded a significant number of successful anticancer drugs, several of which manifest their activities by inducing apoptosis (or programmed cell death) in cancer cells. The Amaryllidaceae alkaloids have similarly distinguished themselves as potent antiproliferative agents, some at the nanomolar level, with selective apoptosis inducing effects demonstrated in a wide variety of cancer cells. The proteolytic enzymes caspases are the key effectors of the apoptotic pathways, the main function of which is, in turn, the activation of caspases. Once activated caspases set in motion an intricately choreographed cascade of events leading to eventual cell death and phagocytosis. The lycorane and crinane group of alkaloids were amongst the first of the Amaryllidaceae for which apoptosis and attendant caspase inducing effects were discovered. These have been central in ongoing efforts to unravel the mechanistic basis to the cytotoxicity of these alkaloids. This review focuses on the various caspases which have been shown to be integral in apoptosis signaling pathways mediated by lycorane and crinane alkaloids.

Over 600 alkaloids have to date been identified in the plant family Amaryllidaceae. These have been arranged into as many as 15 different groups based on their characteristic structural features. The vast majority of studies on the biological properties of Amaryllidaceae alkaloids have probed their anticancer potential. While most efforts have focused on the major alkaloid groups, the volume and diversity afforded by the minor alkaloid groups have promoted their usefulness as targets for cancer cell line screening purposes. This survey is an in-depth review of such activities described for around 90 representatives from 10 minor alkaloid groups of the Amaryllidaceae. These have been evaluated against over 60 cell lines categorized into 18 different types of cancer. The montanine and cripowellin groups were identified as the most potent, with some in the latter demonstrating low nanomolar level antiproliferative activities. Despite their challenging molecular architectures, the minor alkaloid groups have allowed for facile adjustments to be made to their structures, thereby altering the size, geometry, and electronics of the targets available for structure-activity relationship studies. Nevertheless, it was seen with a regular frequency that the parent alkaloids were better cytotoxic agents than the corresponding semisynthetic derivatives. There has also been significant interest in how the minor alkaloid groups manifest their effects in cancer cells. Among the various targets and pathways in which they were seen to mediate, their ability to induce apoptosis in cancer cells is most appealing.

Collisions with buildings cause up to 1 billion bird fatalities annually in the United States and Canada. However, efforts to reduce collisions would benefit from studies conducted at large spatial scales across multiple study sites with standardized methods and consideration of species- and life-history-related variation and correlates of collisions. We addressed these research needs through coordinated collection of data on bird collisions with buildings at sites in the United States (35), Canada (3), and Mexico (2). We collected all carcasses and identified species. After removing records for unidentified carcasses, species lacking distribution-wide population estimates, and species with distributions overlapping fewer than 10 sites, we retained 269 carcasses of 64 species for analysis. We estimated collision vulnerability for 40 bird species with ≥2 fatalities based on their North American population abundance, distribution overlap in study sites, and sampling effort. Of 10 species we identified as most vulnerable to collisions, some have been identified previously (e.g., Black-throated Blue Warbler [Setophaga caerulescens]), whereas others emerged for the first time (e.g., White-breasted Nuthatch [Sitta carolinensis]), possibly because we used a more standardized sampling approach than past studies. Building size and glass area were positively associated with number of collisions for 5 of 8 species with enough observations to analyze independently. Vegetation around buildings influenced collisions for only 1 of those 8 species (Swainson's Thrush [Catharus ustulatus]). Life history predicted collisions; numbers of collisions were greatest for migratory, insectivorous, and woodland-inhabiting species. Our results provide new insight into the species most vulnerable to building collisions, making them potentially in greatest need of conservation attention to reduce collisions and into species- and life-history-related variation and correlates of building collisions, information that can help refine collision management.Correlaciones de las Colisiones de Aves contra Edificios en Tres Países de América del Norte Resumen Las colisiones contra los edificios causan hasta mil millones de fatalidades de aves al año en los Estados Unidos y en Canadá. Sin embargo, los esfuerzos por reducir estas colisiones se beneficiarían con estudios realizados a grandes escalas espaciales en varios sitios de estudio con métodos estandarizados y considerando las variaciones relacionadas a la historia de vida y a la especie y las correlaciones de las colisiones. Abordamos estas necesidades de investigación por medio de una recolección coordinada de datos sobre las colisiones de aves contra edificios en los Estados Unidos (35), Canadá (3) y México (2). Recolectamos todos los cadáveres y los identificamos hasta especie. Después de retirar los registros de cadáveres no identificados, las especies sin estimaciones poblacionales a nivel distribución y las especies con distribuciones traslapadas en menos de diez sitios, nos quedamos con 269 cadáveres de 64 especies para el análisis. Estimamos la vulnerabilidad a colisiones para 40 especies con ≥2 fatalidades con base en la abundancia poblacional para América del Norte, el traslape de su distribución entre los sitios de estudio y el esfuerzo de muestreo. De las diez especies que identificamos como las más vulnerables a las colisiones, algunas han sido identificadas previamente (Setophaga caerulescens), y otras aparecieron por primera vez (Sitta carolinensis), posiblemente debido a que usamos una estrategia de muestreo más estandarizada que en los estudios previos. El tamaño del edificio y el área del vidrio estuvieron asociados positivamente con el número de colisiones para cinco de ocho especies con suficientes observaciones para ser analizadas independientemente. La vegetación alrededor de los edificios influyó sobre las colisiones solamente para una de esas ocho especies Catharus ustulatus). Las historias de vida pronosticaron las colisiones; el número de colisiones fue mayor para las especies migratorias, insectívoras y aquellas que habitan en las zonas boscosas. Nuestros resultados proporcionan una nueva perspectiva hacia las especies más vulnerables a las colisiones contra edificios, lo que las pone en una necesidad potencialmente mayor de atención conservacionista para reducir estas colisiones y de estudio de las variaciones relacionadas con la especie y la historia de vida y las correlaciones de las colisiones contra edificios, información que puede ayudar a refinar el manejo de colisiones.在美国和加拿大, 每年有多达10亿只鸟类死于撞击建筑物。在大空间尺度上跨多个研究地点、采用标准化方法, 并考虑鸟类物种及生活史变异和其它撞击相关因素的研究, 将有助于减少鸟类与建筑物的碰撞。本研究通过整理收集美国、加拿大和墨西哥多个位点 (数量分别为 35 个、3 个和 2 个) 鸟类撞击建筑物的数据来满足以上的研究需求。我们首先收集了所有鸟类尸体并进行物种鉴定。在排除掉不能辨认的尸体、缺少分布范围内种群估计数据的物种、分布区与少于 10 个位点有重叠的物种后, 我们保留了 64 个物种的 269 个死亡事件进行分析。我们根据鸟类的北美种群数量、分布区与研究位点的重叠情况和抽样工作量, 估计了死亡个体≥2 只的 40 种鸟类的撞击脆弱性。本研究确定了最易发生撞击的 10 个物种, 其中包括已经被以往研究提及的物种 (如黑喉蓝林莺 [Setophaga caerulescens]) , 也有首次报道的物种 (如白胸鳾 [Sitta carolinensis]), 这可能是因为我们使用了比以往研究更注重标准化的抽样方法。在有足够观察数据以支持独立分析的 8 个物种中, 有 5 个物种的撞击次数与建筑大小和玻璃面积呈正相关;只有1个物种 (斯氏夜鸫 [Catharus ustulatus]) 的撞击受到建筑物周围植被的影响。生活史也可以预测撞击情况:迁徙鸟类、食虫鸟类和林栖鸟类的撞击次数最多。我们的研究结果为最易发生建筑物撞击伤害的鸟类物种提供了新的见解, 这些物种可能最需要保护以减少撞击, 本研究还深入探究了鸟类物种及生活史变异和其它撞击相关因素, 这些信息有助于改进鸟类撞击管理。【翻译: 胡怡思; 审校: 聂永刚】.