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Invasive alien cacti threaten indigenous biodiversity and negatively impact agricultural productivity in the Eastern Cape Province. One of the most problematic species is jointed cactus, Opuntia aurantiaca Lindley (Cactaceae). A biological control agent, the cochineal insect Dactylopius austrinus De Lotto (Dactylopiidae), is mass-reared and released against O. aurantiaca in the province. The aim of this study was to evaluate the efficacy and safety of D. austrinus against O. aurantiaca through post-release monitoring as perceived by land-users. Post-release monitoring indicated that the number of cladodes of O. aurantiaca declined from 30 (SE ± 1.1)/m2 to 5 (SE ± 1.7)/m2 during a 30-month study period. Forty-seven land-users who had received D. austrinus for O. aurantiaca were interviewed with standardised questionnaires. Most land-users perceived biocontrol as effective, with 71% of land-users reporting a decrease of O. aurantiaca after the release of D. austrinus, and 62% of land-users indicating that the reduction in O. aurantiaca had resulted in environmental and agricultural benefits. Ninety-four per cent of the land-users perceived biocontrol as a safe method without non-target impacts. This study confirms that biological control has been accepted by land-users and they believe it is effective and that mass-rearing of the agent should be increased so that more releases can be made. [ABSTRACT FROM AUTHOR]

We conducted long-term monitoring of Hypogeococcus sp. (Pseudococcidae) as a biocontrol agent for queen of the night cactus (Cereus jamacaru De Candolle). The biocontrol agent was released at three sites representing the regions where the plant is problematic in South Africa, and both agent and plant populations were monitored over time. The proportion of plants producing fruits or flowers decreased by 36% each year, with all plants no longer flowering between two and seven years after release. Plant density reduced by 42% each year after release. Hypogeococcus sp. is an effective agent against C. jamacaru in South Africa. [ABSTRACT FROM AUTHOR]

African lovegrass, Eragrostis curvula (Schrad.) Nees (Poaceae), is a perennial grass native to southern Africa that has become problematic in many countries, most notably in Australia. A biological control programme against E. curvula in Australia has been initiated to mitigate the plant's negative impacts. We present field-based host-specificity observations of natural enemies in the native distribution in South Africa and validate these observations with laboratory based no-choice host-specificity tests. Only three insect species were consistently found utilising E. curvula, namely two stem-galling wasps belonging to the genus Tetramesa (Hymenoptera: Eurytomidae), and a shoot-galling fly (Diptera: Chloropidae). The shoot-galling fly was found to utilise grasses from multiple non-target grass genera and was thus rejected. Both Tetramesa species were recorded on multiple native African Eragrostis species during field host-range surveys, and this relatively broad host range was confirmed by both wasp species completing development on several native Eragrostis species under no-choice conditions in the laboratory. At least three native Australian species (E. parviflora, E. trachycarpa, E. leptocarpa) are predicted to be suitable hosts for both Tetramesa species. Neither Tetramesa species are therefore likely to be suitably host specific for release on E. curvula in Australia. The recent discovery of an adventive population of one of the South African Tetramesa on E. curvula in Australia provides an opportunity to test whether the predicted host range of the species is realised in the introduced distribution. [ABSTRACT FROM AUTHOR]

Grasses are amongst the most abundant and environmentally damaging invasive weeds worldwide. Biological control is frequently employed as a sustainable and cost-effective management strategy for many weeds. However, grasses have not been actively pursued as targets for classical weed biological control due to a perceived lack of sufficiently specialised and damaging natural enemies to use as biological control agents. There are also concerns that the risk posed to economically important crop/pasture species and closely-related native species is too great to consider implementing biological control for invasive grasses. In this paper, we review the literature and demonstrate that grasses can possess suitably host-specific and damaging natural enemies to warrant consideration as potential biological control agents. The risk of grass biological control is no greater than for other weedy taxa if practitioners follow appropriately rigorous risk assessments protocols. [ABSTRACT FROM AUTHOR]

The stem-mining weevil, Pereskiophaga brasiliensis, was a candidate biological control agent for the invasive cactus Pereskia aculeata in South Africa. In host specificity trials, it developed on two indigenous test plant species under choice and no-choice conditions. Pereskiophaga brasiliensis is therefore not suitably host specific for release in South Africa. [ABSTRACT FROM AUTHOR]

Australia and South Africa have a long history of sharing successful biocontrol agents for cactus weeds but other countries, such as Namibia, could also benefit. There are four biological control agents that are widely utilised in South Africa and/or Australia for the control of 10 invasive alien Cactaceae in Namibia. [ABSTRACT FROM AUTHOR]

Chromolaena odorata (L.) R.M. King and H. Robinson (Asteraceae: Eupatorieae) is one of the worst invasive weeds in West Africa, and a serious biotic threat to food security. The stem-galling fly, Cecidochares connexa (Macquart) (Diptera: Tephritidae), a biological control agent for C. odorata, was released in the Ivory Coast in 2003 and first detected in Ghana in 2014. The spatiotemporal distribution and abundance of C. connexa in Ghana was determined by country-wide surveys from 2015 to 2016. Galls were found in varying densities across Ghana but gall densities were consistently low east of Lake Volta. A limited survey conducted in the extreme west of Togo in 2016, found the gall fly also in low numbers. There was a significant correlation between C. connexa gall densities and the distance from the release sites in the Ivory Coast. The distribution and abundance of the gall fly in Ghana could be explained by its spread from the original release sites over time and/or the much drier conditions east of Lake Volta. Cecidochares connexa has dispersed a distance of about 1000 km over a 10-year period and, while there is some evidence that the gall fly is still dispersing towards the east, its range and population size could be limited by the dry climatic conditions in the east of Ghana and in Togo. Actively redistributing the agent over this dry corridor to the more humid and higher rainfall areas of Nigeria, may result in the spread of this agent through the rest of West and Central Africa, thereby aiding the control of C. odorata in the region. [ABSTRACT FROM AUTHOR]

We investigated host-plant utilisation by the candidate biocontrol agentParadibolia coerulea(Coleoptera: Chrysomelidae) on the target plantSpathodea campanulataBeauv. (Bignoniaceae) and a closely related non-target plant,Kigelia africana(Lam.) Benth. (Bignoniaceae). Paired-choice and sequential no-choice experiments were performed and coupled with olfactory discrimination experiments to test the insects’ responses to volatiles from both plant species as well as to cues from conspecific beetles. AlthoughK. africanawas utilised byP. coerulea,S. campanulatawas preferred for both adult feeding and oviposition. Interestingly, whereas females were attracted to olfactory cues emitted byS. campanulata, males demonstrated no such olfactory discrimination. Females were also attracted to cues deposited by males, and males were deterred by cues from other males, but neither sex responded to female olfactory cues. Very few eggs were recorded onK. africanaand none of the larvae that hatched onK. africanasurvived the first instar. BothS. campanulataandK. africanaare suitable for adult feeding, but persistent utilisation ofK. africanain the field is unlikely because larval development is only possible onS. campanulataand because the adult females are strongly attracted to volatiles emitted by the target plant. Nevertheless, ifP. coeruleais released as a biocontrol agent, spill-over adult feeding could potentially occur onK. africanagrowing sympatrically withS. campanulata. BecauseP. coeruleacannot complete its development onK. africana, non-target damage will only occur where the target plant is present, with an intensity dependent on densities of adult beetles locally. [ABSTRACT FROM PUBLISHER]

The article presents some of the promising biological control agents against the invasive African tulip tree, Spathodea campanulata Beauv. (Bignoniaceae), in some Pacific Islands countries like Papua New Guinea, Fiji and Samoa. Among the West Africa arthropods which are potential agents are the Paradibolia coerulea Bryant (Chrysomelidae) flea-beetle, the Bunia pagnana (Drake) (Tingidae) sap-sucking bug, and the Colomerus spathodeae Carmona (Eriophyidae) leaf- and shoot-galling mite.

There is now compelling evidence that the tumour stroma plays an important role in the pathogenesis of cancers of epithelial origin. The pre-eminent cell type of the stroma is carcinoma-associated fibroblasts. These cells demonstrate remarkable heterogeneity with activation and senescence being common stress responses. In this review, we summarise the part that these cells play in cancer, particularly oral cancer, and present evidence to show that activation and senescence reflect a unified programme of fibroblast differentiation. We report advances concerning the senescent fibroblast metabolome, mechanisms of gene regulation in these cells and ways in which epithelial cell adhesion is dysregulated by the fibroblast secretome. We suggest that the identification of fibroblast stress responses may be a valuable diagnostic tool in the determination of tumour behaviour and patient outcome. Further, the fact that stromal fibroblasts are a genetically stable diploid cell population suggests that they may be ideal therapeutic targets and early work in this context is encouraging. [ABSTRACT FROM AUTHOR]

The article discusses a study that determined the association of rheumatoid arthritis (RA) with the risk of having nontuberculous mycobacteria (NTM) infections among Ontario residents. Observed from 2001-2010 were 15-year-old Ontarians who have RA and then identified laboratory-confirmed cases of NTM disease and tuberculosis (TB). Findings showed strong association of NTM disease in patients with RA and higher risk of death for RA patients with NTM.

Background: Mitochondrial DNA (mtDNA) mutations occur in head and neck squamous cell carcinoma (HNSCC) and are most frequently detected in the displacement-loop (D-loop) region. The D-loop is considered to be important because it controls mitochondrial gene expression and mtDNA replication. There is currently no evidence that mtDNA mutations can be used as prognostic or predictive biomarkers in HNSCC.Methods: We used denaturing high performance liquid chromatography to screen the entire mitochondrial genome of six oral squamous cell carcinoma-derived cell lines and then focused on detecting D-loop abnormalities in 34 HNSCC tissue samples.Results: Mitochondrial DNA mutations are not ubiquitous in HNSCC because only half of the cell lines had detectable mtDNA abnormalities following screening of the entire mitochondrial genome and only 18% (6 of 34) of tissue samples had D-loop mutations. There was no correlation between D-loop mutations and determinates of clinical outcome; specifically, tumour stage and the expression of hypoxia-inducible genes included in a highly prognostic hypoxia metagene.Conclusions: Taken together, these data suggest that mtDNA D-loop mutations are stochastic events that may not significantly influence the biology of HNSCC and supports the hypothesis that mtDNA mutations in cancer represent bystander genotoxic damage as a consequence of tumour development and progression. [ABSTRACT FROM AUTHOR]

A Gamma-ray spectroscopic study of excited states of isobaric multiplets has been performed in recent years, with a view to gaining a quantitative understanding of energy differences between excited states in terms of a range of Coulomb and other isospin breaking phenomena. Recently, the experimental programme has been augmented by a study of isobaric analogue states of mirror nuclei populated in mirrored fragmentation reactions. In this presentation, recent results on the $T =\frac{3}{2}$ analogue states in the $T_z =\pm \frac{3}{2}$ mirror pair 53Ni/53Mn will be summarised. In this work, further strong evidence is found for the need to include an anomalous isospin-breaking two-body matrix element for angular-momentum couplings of J = 2, in addition the expected Coulomb contribution, in order to account for the experimental data. [ABSTRACT FROM AUTHOR]

We describe five multi-locus PCR panels incorporating twelve new and seven previously characterized microsatellites, useful for population genetic surveys of white hake. All but one locus are polymorphic with an average allelic richness of 14.26 (1.00-50.45 range) and mean observed and expected heterozygosities of 0.680 (0.221-0.888 range) and 0.738 (0.269-0.953 range), respectively. Three loci do not fit Hardy-Weinberg expectations suggesting internal genetic structuring within the sampled population, consistent with previous reports. These multi-locus panels will be used to determine population structure of white hake in the Northwest Atlantic, clarify important factors regulating its population dynamics and help establish much needed conservation efforts to recover this species in this region. [ABSTRACT FROM AUTHOR]