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There has been an increase in the use of elastomers in the biomedical industry. Recent developments in utilising elastomers for use in orthopaedic implants has shown the great potential of these materials for long-term implantation. Elastomers are being developed for applications in tissue engineering, polymeric scaffolds and synthetic implants, all with the aim of repairing or maintaining orthopaedic joints in working order. The aim of this review is to discuss current developments in elastomeric orthopaedic implants and their most utilised materials namely silicones, polyurethanes and hydrogels. Polyurethane and silicone elastomers are commonly used in bulk implantable devices due to their good mechanical properties, chemical resistance and biocompatibility. Other materials such as polycarbonate urethanes (PCUs) are being utilised as means to protect the joints due to their superb mechanical properties and wear characteristics. The range of applications of elastomers vary from hip joint replacements, such as in the case of the TriboFit implant, meniscal implants, and first metatarsophalangeal joint replacements. More recently hydrogels have been utilised as coatings for increased lubrication in joint replacements, as a substitute for articular cartilage. Applications of hydrogels vary from improving the collagen and proteoglycan content of the joint to improving the load distribution across the joint in arthritic knee joints. The use of elastomers in orthopaedic implants is still in its infancy; and whilst a large amount of the research being done is still in the prototype stages, the potential of these materials and devices is unlimited., peer-reviewed

There has been an increase in the use of elastomers in the biomedical industry. Recent developments in utilising elastomers for use in orthopaedic implants has shown the great potential of these materials for long-term implantation. Elastomers are being developed for applications in tissue engineering, polymeric scaffolds and synthetic implants, all with the aim of repairing or maintaining orthopaedic joints in working order. The aim of this review is to discuss current developments in elastomeric orthopaedic implants and their most utilised materials namely silicones, polyurethanes and hydrogels. Polyurethane and silicone elastomers are commonly used in bulk implantable devices due to their good mechanical properties, chemical resistance and biocompatibility. Other materials such as polycarbonate urethanes (PCUs) are being utilised as means to protect the joints due to their superb mechanical properties and wear characteristics. The range of applications of elastomers vary from hip joint replacements, such as in the case of the TriboFit® implant, meniscal implants, and first metatarsophalangeal joint replacements. More recently hydrogels have been utilised as coatings for increased lubrication in joint replacements, as a substitute for articular cartilage. Applications of hydrogels vary from improving the collagen and proteoglycan content of the joint to improving the load distribution across the joint in arthritic knee joints. The use of elastomers in orthopaedic implants is still in its infancy; and whilst a large amount of the research being done is still in the prototype stages, the potential of these materials and devices is virtually unlimited., peer-reviewed

This study investigated seed germination in five indigenous species of plants in the Maltese Islands, predominantly occurring in coastal garrigue habitats but also inland, namely Drimia maritima, Periploca angustifolia, Asparagus aphyllus, Myrtus communis, and Pancratium maritimum. Different germination protocols were tested for one or more populations, namely: four different temperature regimes - constant 15, 20 and 25°C as well as alternating 23.5/15°C; three different photoperiods, 12/12, 16/8 and 0/24 light/dark. The best germination results for each species are provided and additional notes on the species and germination behaviour are also given., peer-reviewed

The UN’s 2030 Agenda for Sustainable Development calls for the preservation of biodiversity, which is threatened due to habitat degradation and climate change. Actions to enhance restoration and resilience of habitats to reduce biodiversity loss are needed. Though in-situ conservation is considered the best way to preserve biodiversity where species can persist with all their natural ecological interactions, the latter element is often ignored. Criticalities can arise when ex-situ grown indigenous plants are translocated in-situ, without their natural soil microbial associations, especially in a Mediterranean climate where abiotic stresses are severe. Ectomycorrhizal fungi (ECM) are fundamental for terrestrial ecosystems, enhancing plant productivity, alleviating abiotic and oxidative stress, and regulating macronutrients recycling. The aim of the project was to investigate the use of indigenous ECM to enhance acclimatization and survival of ex-situ grown plants translocated for habitat restoration., peer-reviewed

The Mediterranean basin is a biodiversity hotspot where many species are under threat and action for restoration is needed. One of these species is Coronilla valentina subsp. glauca, with a localised distribution in the Maltese Islands. Seed priming is the controlled hydration of seeds in water or a solution of low osmotic potential to initiate the germination metabolism before sowing. Hydropriming is an economical technique that improves seed water-uptake efficiency and is useful in areas with unpredictable abiotic stresses namely high temperature and drought. The aim of this study was to investigate the efficiency of hydropriming treatment on seeds of C. valentina subsp. glauca using morphocolorimetric analysis and germination dynamics data, peer-reviewed

Micropropagation has the advantage of genetic homogeneity and reduces difficulties related to obtaining pathogen-free plant material. However, some plant species present challenging problems when used for in vitro culture. This research work dealt with the micropropagation of Quercus pubescens Willd. with the aim of enhancing the percentage proliferation and rooting from micro-cuttings. Microcuttings, containing apical or axillary buds, were taken from two year-old branches using a clone of Q. pubescens grown at the Forest Nursery of Sant’Angelo in Vado, Pesaro-Urbino, Marche, Italy. A preliminary screening of the proliferation was performed using increasing concentration of benzylaminopurine (BA) in the culture medium (0.25; 0.5; 0.75; 1 mg/l) in order to select the best hormones to use in the experiment. From the results it was possible to deduce that BA plays a key role in influencing shoot proliferation, leading to the formation of a callus and to the production of new shoots. Moreover, we observed that, especially higher BA concentrations promoted the production of a larger number of shorter shoots compared to low concentrations, that produced the small number of longer shoots. Furthermore, these trials have shown that, in order to have a large number of seedlings with an optimal shoot length, it is necessary to divide the process of propagation in two phases. The first phase involves a high concentration of BA, with the aim of increasing the number of new micro-cuttings; the second phase, with lower levels of BA, to increase the length of the shoots. With regards to root induction, the hormone selected was indole-butyric acid (IBA). Results showed that micro-cutting exposed for 24h to higher hormone concentration gave the best results for root induction and root length. The study developed an efficient method for the micropropagation of Q. pubescens for the selection of genotypes in vitro and sterile (e.g., free microorganisms and insects) conditions. It is envisaged that the development of this protocol paves the way for further utilisation of micro-propagated Q. pubescens in new areas of research, such as in vitro mycorrhization., peer-reviewed

Nitinol, a thermoelastic Ni-Ti Shape Memory Alloy (SMA) with approximately 50 at. % Ti, is adopted in a wide range of medical equipment and devices used in interventional radiology, orthopaedics, neurology and cardiology, in particular as a smart material for stents. In this work, NiTi real stents and massive samples before and after different Powder Immersion Reaction Assisted Coating (PIRAC) treatments have been investigated by using two neutron techniques: (1) Small and Ultra-Small Angle Neutron Scattering (SANS, USANS) for nano- and micro-scale characterization, obtaining information on structure and the effects due to the coating treatment; and (2) High-Resolution Neutron Diffraction (HRND), evaluating the macrostrain components resulting from angular shifts of diffraction peaks and the micro-strains in the plastically deformation region by means of profile-broadening analysis. The obtained results contribute: improving knowledge of defects and other key features of the materials complementary to those achieved by using traditional examination techniques; helping to better understand the functional characteristics of Nitinol parts and predict the material’s mechanical behaviour., peer-reviewed

The Maltese Islands are located in the central Mediterranean sea and have a strongly bi-seasonal climate characterised by mild, wet winters and hot, dry summers. The average annual precipitation is 530 mm. Trichoderma spp. are endophytic, soil-borne fungi, green-spored filamentous ascomycetes and are found world wide. This genus was first described by Persoon 1794 and Tulasne 1865. According with Druzhinina et al. 2011, to date at least 1100 strains of Hypocrea (sexual telomorphic stage), and Trichoderma (asexual anamorphic stage), have been identified, and many new species are being recognized. Trichoderma spp. are widely studied due to their uses as mycoparasites biocontrol agents. Furthermore, they stimulate plant growth, suppress plant diseases by one or more different direct and/or indirect mechanisms and solubilize nutrients. Some strains can induce host growth under abiotic stress, and improve seed germination under saline conditions. These fungi are producers of a number of secondary metabolites with antibiosis properties and they also have several biotechnological applications. On the other hand, T. harzianum, T. longibrachiatum and T. viride have been recognized as opportunistic pathogens of immunocompromised persons. Trichoderma is a powerful organism to study for its capacity of helping good practise against climate change. Since, few studies on Trichoderma spp. are recorded on the Maltese Island, the present work was aimed to investigate presence, isolation and preservation on different substrates., peer-reviewed

Cancer is the second leading cause of death globally and was responsible for 8.8 million deaths in 2015. Among the most common type of cancer that kill people were breast, cervical and bold cancers (OMS). The economic impact of cancer is significant and is increasing. The total annual economic cost of cancer in 2010 was estimated at approximately US$ 1.16 trillion (1). Therefore, the resort to the use of the natural product becomes more and more propitious specially in patients that develop multidrug resistance. The use of essential oil for their anticancer activity dated to 1960 (2)(Bagora et al., 2014) Aim: After the chemical characterization of the leaf essential oil from Juniperus ocycedrus (Cupressaceae), the in vitro cytotoxic activity of this oil on MCF7 and K562 was tested using MTT assay., peer-reviewed

Some plants present challenging obstacles when grown by in vitro culture, they may be recalcitrant, hampering the development of reliable regeneration techniques. This ‘recalcitrant behaviour’ is genetically driven, so it is difficult to control by environmental and nutritional manipulation in microculture. Plants which are difficult to work with are usually perennials with complex seasonal life cycles. Quercus species show short growth spurts per season, when they stop growing until the next season. Such species may be called episodic and are not always successfully used in microculture and biotechnology. Micropropagation has the advantage of genetic homogeneity and avoids difficulties related to obtaining sterile plant material., peer-reviewed

The composition of the essential oil (EO) obtained from dry leaves of Chiliadenus bocconei Brullo (Asteraceae subfam. Inulae), a Maltese endemic aromatic plant, collected in two different seasons, was evaluated in this work. The main EO components identified in the summer foliage were camphor (25.6%), borneol (27.1%) and τ-cadinol (13.9%). In the winter foliage τ-cadinol was the most represented compound (59.5%), followed by camphor (13.1). A comparison is also made between the EO composition of the two samples of C. bocconei and the EO obtained from different aerial parts of C. lopadusanus, an endemic plant of Lampedusa Island, another Mediterranean Island.

NEPTUME is an R&I project funded by the Malta Council for Science and Technology (MCST), dealing with the treatment of raw municipal effluent to produce quality second class water for irrigation (and other) purposes. This paper presents an innovative two-stage process which uses the combination of a Moving Bed Biofilm Reactor (MBBR) coupled with a Membrane Bioreactor Filtration (MBR) incorporating the benefits of both processes. This setup produces a very high quality disinfected second class treated sewage effluent (TSE) (COD, Bajada New Energy, Bitmac ltd., Econetique, Energy Investment, JMV Vibro Blocks, Solar Engineering., peer-reviewed

Propolis is a complex honeybee product deposited in the beehives, where it protects the hive and its occupants from microbial infection. Propolis has several reported medical applications in view of its numerous bioactive properties. The water insoluble fraction of crude Maltese honeybee propolis was extracted in methanol. Analysis by gas chromatography – mass spectrometry (GC-MS) showed the diterpenoid totarol to be the predominant constituent in all samples. The evaporated methanol residue was dissolved in dimethyl sulphoxide (DMSO) and used for cytotoxicity testing on human cancer cell lines using standard 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assays. Results obtained show that the propolis collected from Malta has cytotoxic activity in cancer cells in vitro. However, propolis collected from different sites, only a few miles apart and at different times of the year, showed marked variations in the cytotoxicity, which correlated clearly with totarol content. This reflects the differences in the species of plants, on which the bees had foraged and indicates the importance of collection site and season of collection on the bioactivity of propolis products., peer-reviewed

Following the success of forming a carbon S-phase (expanded austenite) surface layer on medical grade Ni-free austenitic stainless steel by DC plasma carburising, the established commercial carburising process Kolsterising® was performed on both Ni-containing (AISI 304) and Ni-free austenitic stainless steels. While the Ni-containing stainless steel responded very well to Kolsterising®, the Ni-free alloy did not. The carbon absorption and the hardness of the Kolsterised® Ni-free alloy are inferior to Kolsterised® AISI 304 Ni-containing stainless steel, however, the hardness of the untreated Ni-free alloy was doubled by Kolsterising®. The response of both Kolsterised® Ni-free and Ni-containing alloys to pitting, crevice corrosion and intergranular corrosion resistance was similar. From this work it can be concluded that the Kolsterised® austenitic stainless steels do not suffer from intergranular corrosion but are susceptible to intragranular pitting when tested in boiling sulphuric acid and copper sulphate solution. It was also observed that Kolsterising® improves significantly the pitting and crevice corrosion resistance of the alloys used in this study., peer-reviewed

Protein prenylation is a post-translational addition of a lipophilic farnesyl or geranylgeranyl moiety derived from the pyrophosphate substrates, intermediates of the mevalonate pathway. Prenylation of Ras-related small GTP-binding proteins and heterotrimeric G proteins constitute protein activation events associated with cellular proliferation. The monoterpenes limonene and perillyl alcohol inhibit protein isoprenylation resulting in cell cycle arrest and induction of apoptosis. Clinical trials of d-limonene and perillyl alcohol resulted in dose limiting toxicity. Reducing the dosage of isoprenoids, while maintaining the antiproliferative effect is a challenge. Interestingly, the limiting factor of the mevalonate pathway, HMG CoA reductase, is controlled at translation level and hence sensitive to mTOR activity. The purpose of this study was to investigate the dose response using a combinatory treatment of isoprenoids and rapamycin (mTOR inhibitor), on various solid tumour cell line models. 3 solid tumour cell lines, namely PC3 (prostate) C32 (melanoma) and A549 (lung), were chosen on the basis of sensitivity to the mTOR inhibitor, rapamycin. Cytotoxicity assays using XTT were performed on the cell lines treated with Limonene, Perillyl alcohol and α-Pinene. In this study XTT assays were used to quantify viable cells after treatment with Isoprenoids and Rapamycin alone or in combination. Dosages at IC50s were used to measure apoptosis by Annexin V staining and flow cytometry. The C32 and PC3 cell lines were sensitive to rapamycin treatment, resulting in a decrease in cell viability by more than 20%, but retaining a constant growth curve thereafter. A549 was not sensitive to rapamycin at all concentrations tested. For all combinatory treatments, 50ng/ml rapamycin was selected. The viability of PC3 and C32 cell lines decreased significantly by the combinatory effect of 50ng/ml rapamycin and isoprenoids. Although cell death was enhanced after sensitisation with rapamycin, other mechanisms of loss of cellular viability, other than apoptosis, have a major role. Our results show a statistically significant reduction in IC50 of various isoprenoids, following pre-sensitization with 50ng/ml of rapamycin in the prostate cell line (PC3) and the melanoma cell line (C32). Hence this novel combination of drugs targeting two mechanisms that converge on a common target, provide a higher efficacy compared to using either drug on its own. This merits further investigation to characterise the mechanism/s of viability suppression in the solid tumour cellular models., peer-reviewed

Sarcopoterium spinosum (L.) Spach (Rosaceae) is a dwarf shrub, 30–60 cm in height, with branches ending in dichotomous, leafless thorns (1), that recruits both sexually and clonally (Figure 1, 2). It dominates eastern-mediterranean shrublands known as “bathah” in Israel and “phrygana” in Greece (2). Its southern distribution is in the Northern Negev of Israel. In semi-arid ecosystems, shrublands dominated by S. spinosum are often formed following recolonization of old-fields (1). In the W-Mediterranean basin the species occurs in locations on the Balkan Coast, in Italy and in Tunisia (Djerba); in addition, a small population of S. spinosum is also recognizable in Malta (3). The germination behaviour of three populations (Sardinia - Italy, Chios – Greece and Malta) of Sarcopoterium spinosum was investigated under controlled laboratory conditions at the Sardinian Germplasm Bank (BG-SAR). Chios population is situated in the central part of the distribution area, while Malta and Sardinia represent two disjunct populations at its western margin (Figure 3). The seed germination occurs inside the fruits (1,4). Each fruit contains several seeds but usually produces one seedling (1,4). Aim of this work was to study seed viability and germination of Sarcopoterium spinosum and also to compare the germinative behavior of central and border populations., peer-reviewed

Aims: The main aim of the study is the production of an extract from a local indigenous plant that induces the differentiation of the osteoblast cell line MC3T3-E1 without inducing an estrogen growth factor response in the breast cancer cell line MCF-7. Methods: A wide range of different methodologies have been used. Methanol extraction has been utilized for the extraction process. Using the osteoblast cell line MC3T3-E1, titrations were performed so as to obtain the working concentrations for betaoestradiol, the extracts, and an already commercialized product (Lignan). To determine the cytotoxicity, XTT assays were performed on the different compounds tested. A chemiluminescence method has also been utilized to directly measure the osteogenesis rate by measuring the uptake of the stain Alizarin red for calcium mineralization (bone matrix). Western blotting is being used to measure the activation of the Estrogen Receptor (ER-alpha) by using a specific phospho-antibody. Real time-PCR will be utilized for expression studies of identified oestradiol response genes. Results: Using methanol reflux, two different extracts have been produced. The working concentrations of the test compounds have already been identified and XTT assays have showed us that none of the test compounds tested (beta-oestradiol, lignan, and carob pod extract) is cytotoxic. The osteogenesis rate has been quantified and after 15 days, a 3.6 fold increase in osteogenesis has been obtained with beta-oestradiol and a 7.6 fold increase in osteogenesis has been obtained with Lignan, when compared with a no factor control. Out of the 2 extracts produced, one of them did not produce any significant results. However, pilot studies conducted on the second extract have shown very promising results and the current experiments being performed will determine the ideal working concentration of this extract. We also confirmed the work done by Takamizawa et al (2004) where whilst ascorbic acid 2-phosphate stimulates osteogenesis, ascorbic acid showed a repressive effect depending on concentration used. Conclusions: To date we can conclude that both betaoestradiol, and Lignan increase the rate of osteogenesis. Although the primary extract did not produce any significant results, pilot studies on the secondary extract have shown us that the results are very promising. The effect of these test compounds on ER-alpha and on oestradiol response genes still needs to be determined., peer-reviewed