Sutherlandia frutescens: The meeting of science and traditional knowledge

Sutherlandia frutescens (L.) R.Br. (syn. Lessertia frutescens (L.) Goldblatt and J.C. Manning) is an indigenous medicinal plant extensively used in South Africa to treat a variety of health conditions. It is a fairly widespread, drought-resistant plant that grows in the Western, Eastern, and Northern Cape provinces and some areas of KwaZulu-Natal, varying in its chemical and genetic makeup across these geographic areas.1 Sutherlandia is widely used as a traditional medicine. Extensive scientific studies are being carried out on the safety, quality, and the efficacy of this medicinal plant to validate the traditional claims, elucidate the bioactive constituents, and conduct clinical trials. This has resulted in a unique situation in South Africa’s history, where traditional knowledge and science intersect to provide insight into this popular plant. This photoessay attempts to illustrate the interlinkage of science with the indigenous knowledge of traditional healers, the local knowledge of people who care for the sick, product development, and innovation agenda of the country as it relates to this plant.Web of Scienc

The context of chemical communication driving a mutualism

Recent work suggests that Drosophila and Saccharomyces yeasts may establish a mutualistic association, and that this is driven by chemical communication. While individual volatiles have been implicated in the attraction of D. melanogaster, the semiochemicals affecting the behavior of the sibling species D. simulans are less well characterised. Here, we comprehensively scrutinize a broad range of volatiles produced by attractive and repulsive yeasts to experimentally evaluate the chemical nature of communication between these species. When grown in liquid or on agar-solidified grape juice, attraction to S. cerevisiae was primarily driven by 3-methylbutyl acetate (isoamyl acetate) and repulsion by acetic acid, a known attractant to D. melanogaster (also known as vinegar fly). Using T-maze choice tests and synthetic compounds we show that these responses were strongly influenced by compound concentration. Moreover, the behavioral response is further impacted by the chemical context of the environment. Thus, chemical communication between yeasts and flies is complex, and is not simply driven by the presence of single volatiles, but modulated by compound interactions. The ecological context of chemical communication needs to be taken into consideration when testing for ecologically realistic responses

Data Recovery Excavations of the Carriage House, Greenhouse, and Greenhouse/Carriage House Well at Gore Place, Waltham, Massachusetts

Excavations and ground penetrating radar at Gore Place in Waltham, Massachusetts, examined the original 1793 carriage house site, the 1806 greenhouse, and the greenhouse/carriage house well, all associated with Christopher and Rebecca Gore. The carriage house was moved in 1968, and its cellar was filled at that time. Mechanical removal of the fill in a portion of the carriage house cellar revealed that the lower portion of at least the rear (north) foundation wall is well preserved along with the cellar floor. Documentary evidence indicated that the carriage house cellar had been used for manure (compost) preparation, while the first floor was used to house horses and to store gardening tools and firewood. Four excavation units set into the cellar floor revealed no evidence of its former use for manure production (such as organic staining) indicating that it had been thoroughly cleaned. The artifacts present in the floor units represent a considerable time period from that of the Gores through to the early 20th century. The majority of objects date to the Gore period, and the wide variety may reflect the incorporation of refuse into manure production. Investigations north of the structure showed that some of the soil in the parking lot constituting the western portion of Gore’s vegetable garden was removed and replaced with a uniform mixture of sand and gravel, probably at the time the carriage house was moved. While the gravel is at least 2 m deep close to the carriage house foundation, its depth lessens with distance northward, since shovel testing in 2004 showed intact dark brown loamy soil beginning at a depth of 35 to 50 cm below driveway gravel and sand bedding at 20 and 40 m north of the carriage house foundation. Early 19th-century maps indicated that the greenhouse was roughly 60 feet (18 m) long and 15 to 21 feet (up to 6.5 m) wide with a small extension on the west end. Fifty-two square meters were excavated at the west end, uncovering the trapezoidal brick fl oor of the extension and an associated stone drain, ground surfaces contemporary with the greenhouse, post holes for a fence that separated the greenhouse area from the carriage house, layers relating to the greenhouse’s destruction (early 1840s), and later landscaping features including a stone wall and two drains. Documentary, archaeological, and geophysical data suggest that the greenhouse was a formal space intended to grow and display exotic plants and that it was built in the relatively new lean-to style, with a tall back wall and short front wall. The artifact assemblage included architectural elements, tools and small finds related to the greenhouse operation (including the remains of at least 149 planting pots), and bone stockpiled for soil enrichment. The greenhouse was constructed by the Gores during a period of intense interest in agricultural experimentation by members of the Massachusetts commercial and political elite. Scholars have argued that these men used the positive associations of agriculture to offset some of the contemporary negative connotations of commerce. This report examines the greenhouse both as a space for the display of exotic plants in the context of this scientifi c agricultural movement and posits that Rebecca Gore may have played a signifi cant role in managing it

Quantifying variation in the ability of yeasts to attract Drosophila melanogaster

Yeasts that invade and colonise fruit significantly enhance the volatile chemical diversity of this ecosystem. These modified bouquets are thought to be more attractive to Drosophila flies than the fruit alone, but the variance of attraction in natural yeast populations is uncharacterised. Here we investigate how a range of yeast isolates affect the attraction of female D. melanogaster to fruit in a simple two choice assay comparing yeast to sterile fruit. Of the 43 yeast isolates examined, 33 were attractive and seven repellent to the flies. The results of isolate-versus-isolate comparisons provided the same relative rankings. Attractiveness varied significantly by yeast, with the strongly fermenting Saccharomyces species generally being more attractive than the mostly respiring non-Saccharomyces species (P = 0.0035). Overall the habitat (fruit or other) from which the isolates were directly sampled did not explain attraction (P = 0.2352). However, yeasts isolated from fruit associated niches were more attractive than those from non-fruit associated niches (P = 0.0188) regardless of taxonomic positioning. These data suggest that while attractiveness is primarily correlated with phylogenetic status, the ability to attract Drosophila is a labile trait among yeasts that is potentially associated with those inhabiting fruit ecosystems. Preliminary analysis of the volatiles emitted by four yeast isolates in grape juice show the presence/absence of ethanol and acetic acid were not likely explanations for the observed variation in attraction. These data demonstrate variation among yeasts for their ability to attract Drosophila in a pattern that is consistent with the hypothesis that certain yeasts are manipulating fruit odours to mediate interactions with their Drosophila dispersal agent. © 2013 Palanca et al

Longitudinal time-lapse in vivo micro-CT reveals differential patterns of peri-implant bone changes after subclinical bacterial infection in a rat model

Subclinical infection associated with orthopedic devices can be challenging to diagnose. The goal of this study was to evaluate longitudinal, microcomputed tomography (microCT) imaging in a rat model of subclinical orthopedic device-related infection caused by Staphylococcus epidermidis and four different Cutibacterium (previously Propionibacterium) acnes strains, and compare outcomes with non-inoculated and historical S. aureus-inoculated controls. Sterile screws or screws colonized with bacteria were placed in the tibia of 38 adult Wistar rats [n = 6 sterile screws; n = 6 S. epidermidis-colonized screws; n = 26 C. acnes-colonized screws (covering all three main subspecies)]. Regular microCT scans were taken over 28 days and processed for quantitative time-lapse imaging with dynamic histomorphometry. At euthanasia, tissues were processed for semiquantitative histopathology or quantitative bacteriology. All rats receiving sterile screws were culture-negative at euthanasia and displayed progressive bony encapsulation of the screw. All rats inoculated with S. epidermidis-colonized screws were culture-positive and displayed minor changes in peri-implant bone, characteristic of subclinical infection. Five of the 17 rats in the C. acnes inoculated group were culture positive at euthanasia and displayed bone changes at the interface of the screw and bone, but not deeper in the peri-implant bone. Dynamic histomorphometry revealed significant differences in osseointegration, bone remodeling and periosteal reactions between groups that were not measurable by visual observation of still microCT images. Our study illustrates the added value of merging 3D microCT data from subsequent timepoints and producing inherently richer 4D data for the detection and characterization of subclinical orthopedic infections, whilst also reducing animal use

The non-steroidal anti-inflammatory drug carprofen negatively impacts new bone formation and antibiotic efficacy in a rat model of orthopaedic-device-related infection

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for pain management during recovery from orthopaedic surgery. NSAID use is associated with increased risk of bone healing complications but it is currently unknown whether NSAIDs increase the risk of developing an orthopaedic-device-related infection (ODRI) and/or affects its response to antibiotic therapy. The present study aimed to determine if administration of the NSAID carprofen [a preferential cyclooxygenase-2 (COX-2) inhibitor] negatively affected Staphylococcus epidermidis (S. epidermidis) bone infection, or its subsequent treatment with antibiotics, in a rodent ODRI model. Sterile or S. epidermidis-contaminated screws (~ 1.5 x 106 CFU) were implanted into the proximal tibia of skeletally mature female Wistar rats, in the absence or presence of daily carprofen administration. A subset of infected animals received antibiotics (rifampicin plus cefazolin) from day 7 to 21, to determine if carprofen affected antibiotic efficacy. Bone changes were monitored using in vivo µCT scanning and histological analysis. The risk of developing an infection with carprofen administration was assessed in separate animals at day 9 using a screw contaminated with 102 CFU S. epidermidis. Quantitative bacteriological analysis assessed bacterial load at euthanasia. In the 28-day antibiotic treatment study, carprofen reduced osteolysis but markedly diminished reparative bone formation, although total bacterial load was not affected at euthanasia. Antibiotic efficacy was negatively affected by carprofen (carprofen: 8/8 infected; control: 2/9 infected). Finally, carprofen increased bacterial load and diminished bone formation following reduced S. epidermidis inoculum (102 CFU) at day 9. This study suggests that NSAIDs with COX-2 selectivity reduce antibiotic efficacy and diminish reparative responses to S. epidermidis ODRI

Securitisation in South Africa: Historic deficiencies and future outlook

While American investors have been able to buy mortgage-backed securities  since the late 1970s and asset-backed securities since the mid-1980s, investors  in South Africa have not become involved in this growing market.  Securitisation also spread to Europe, South America, Asia and Australia during  the 1980s. The first securitisation in South Africa was completed in 1989, but  since then only a few securitised products have been offered to the investment  community. The aim of this article is to investigate the reasons for the lack of  growth in securitisation in South Africa and to determine whether securitisation  will grow to be a significant market in South Africa. The methodology used  includes interviews held with investors, securitisation specialists and other  structured finance specialists from the banking community. Experience from  other countries is noted and included in this article</jats:p