Pereskia aculeata Muller (Cactaceae) Leaves: Chemical Composition and Biological Activities

The aims of this work were to study the chemical composition of the essential oil from the leaves of Pereskia aculeata and to evaluate some biological activities of three leaf extracts. The phenolic content, antioxidant activity, and in vitro antimicrobial and antifungal activities were determined. The methanol extract showed antioxidant activity (EC₅₀ 7.09 mg/mL) and high polyphenols content (15.04 ± 0.31 mg gallic acid equivalents (GAE)/g). The petroleum ether extract exhibited potent antibacterial activity against Escherichia coli, whereas the chloroform extract showed inhibitory activity against Bacillus cereus and Staphylococcus aureus. The petroleum ether and methanol extracts were more effective in inhibiting the growth of Aspergillus versicolor. The possible cytotoxicity of extracts on neuroblastoma SH-SY5Y cancer cell line and the influence on adenylate cyclase (ADCY) expression was also studied. P. aculeata chloroform extract showed antiproliferative activity with an IC₅₀ value of 262.83 µg/mL. Treatments of SH-SY5Y neuroblastoma cells with 100 µg/mL of methanol extract significantly reduced ADCY1 expression.     

Diffusion bonding of TiAl using Ni/Al multilayers

With the stimulus of temperature and pressure Ni and Al can quickly react and produce the intermetallic compound NiAl. This reaction is highly exothermic and high temperatures can be attained in the surroundings. These characteristics make Ni/Al multilayers very attractive to technological applications as localised heat sources. In this study, Ni/Al multilayer thin films are used to promote bonding between TiAl intermetallic alloys. Ni and Al alternated nanolayers were deposited by d.c. magnetron sputtering onto TiAl samples, with periods of 5, 14 and 30 nm. Joining experiments were performed at 900 °C for 60 or 30 min, in a vertical furnace with a vacuum level better than 10⁻² Pa. Applied pressures of 5 MPa were tested. The microstructure of the cross-sections of the bond interface was analysed by energy dispersive X-ray spectroscopy and characterised by scanning electron microscopy. The observation of the microstructure for 14 and 30 nm period multilayers revealed sound bonding, while for 5 nm period porosity and cracks within the interlayer thin film were observed. The interface is divided into three distinct zones: one with columnar grains, another with very small equiaxed grains and the third with larger equiaxed grains. The joining process appears to depend on the diffusion of Ni and Ti across the interface and is assisted by the nucleation of nanometric grains at the interface. The mechanical strength of the joints was evaluated by shear tests. The bonds produced at 900 °C/5 MPa/60 min/14 nm exhibited the highest shear strength of 314 MPa.     

The protective ability of Mediterranean dietary plants against the oxidative damage: The role of radical oxygen species in inflammation and the polyphenol,flavonoid and sterol contents

Ten hydroalcoholic extracts of edible plants from the Calabria region (Italy) were evaluated for their in vitro antioxidant and antiradical properties and in vivo topical anti-inflammatory activity. All the extracts had radical-scavenging and/or antioxidant properties, the most active plants being hawkweed oxtongue and viper’s bugloss. The best free radical (DPPH·)-scavenging activity was found in hawkweed oxtongue and chicory leaves extracts (IC₅₀ = 25 and 26 μg/ml, respectively). Hawkweed oxtongue, poppy and viper’s bugloss extracts showed the greatest inhibition of linoleic acid oxidation (IC₅₀ = 3 μg/ml). Viper’s bugloss and hawkweed oxtongue extracts had the greatest antioxidant effect on bovine brain peroxidation (IC₅₀ = 11 and 22 μg/ml). All the extracts also showed an anti-inflammatory effect: 300 μg/cm² provoked oedema reductions ranging from 18% to 43%. Cress was the most active plant. Chicory leaves contained the highest amount of phenolics (190 mg/g) whilst Rush crimps contained the highest amount of flavonoids (32.9 mg/g), followed by hawkweed oxtongue (15.8 mg/g). Cress contained the highest number of sterols. Among them, γ-sitosterol (12.2%) and ergost-5-en-3-ol (3β) (4.5%) were found to be the major constituents. Moreover, three of the identified molecules (stigmasta-5,23-dien-3β-ol, stigmasta-5,24(28)-dien-3-ol (3β,22E) and 9,19-cyclolanost-24-en-3-ol (3β)) were found in this plant only.     

Synbiotic potential of carrot juice supplemented with Lactobacillus spp. and inulin or fructooligosaccharides

BACKGROUND: The influence of the addition of two probiotic strains, Lactobacillus rhamnosus and Lactobacillus bulgaricus, and the prebiotic components inulin and fructooligosaccharides on carrot juice was investigated in order to evaluate the possibility of producing a functional vegetal beverage. RESULTS: Both bacterial strains were capable of growing in carrot juice, reaching nearly 5 × 10⁹ colony‐forming units after a 48 h fermentation, and the pH was reduced to 3.5–3.7 or below. The viable cell counts of the two lactobacilli in the fermented juice after 4 weeks of storage at 4 °C, demonstrated good survival of the two strains at low pH. Some biochemical characteristics of the fermented juice, such as β‐carotene content and antioxidant activity, were also preserved, indicating that the metabolism of the Lactobacillus spp. did not degrade these nutritional components after 4 weeks of storage at 4 °C. The positive effect was more evident when the juice was inoculated with Lactobacillus rhamnosus. The presence of inulin and fructooligosaccharides did not alter the cell counts or the biochemical characteristics of the fermented juice. CONCLUSION: We propose this as a health juice and functional beverage for vegetarians or consumers who are allergic to dairy products. Copyright © 2008 Society of Chemical Industry     

Study of the co-pyrolysis of biomass and plastic wastes

This work aimed to study the recovery of two types of waste by the process of pyrolysis. The obtained results show that the adding of a plastic mix improves the overall efficiency of the slow pyrolysis of pine. Therefore, it was possible to achieve higher liquid yields and less solid product than in the classic slow pyrolysis carbonization of biomass. The obtained liquids showed heating values similar to that of heating fuel oil. The gas products had energetic contents superior to that of producer gas, and the obtained solid fractions showed heating values higher than some coals. There were also identified some typical products of fast biomass pyrolysis used as raw material in several industries. The effects of experimental conditions in product yield and composition were also studied. The parameters that showed higher influence were (with its increase): reaction time on gas product composition (increase of the alkane content) and on liquid composition (increase in aromatics content); reaction temperature on product yield (decrease of liquid yield with increase of solids and gases) and on gas product composition (increase in alkane content); initial pressure on liquid composition (increase in the aromatics content) and mainly the pine content of the initial mixture on products yield (increase of gas and solid yield with a decrease in liquids) and on the gas product composition (favouring CO and CO₂ formation). An erratum to this article can be found at     

Exosite Binding in Thrombin: A Global Structural/Dynamic Overview of Complexes with Aptamers and Other Ligands

Thrombin is the key enzyme of the entire hemostatic process since it is able to exert both procoagulant and anticoagulant functions; therefore, it represents an attractive target for the developments of biomolecules with therapeutic potential. Thrombin can perform its many functional activities because of its ability to recognize a wide variety of substrates, inhibitors, and cofactors. These molecules frequently are bound to positively charged regions on the surface of protein called exosites. In this review, we carried out extensive analyses of the structural determinants of thrombin partnerships by surveying literature data as well as the structural content of the Protein Data Bank (PDB). In particular, we used the information collected on functional, natural, and synthetic molecular ligands to define the anatomy of the exosites and to quantify the interface area between thrombin and exosite ligands. In this framework, we reviewed in detail the specificity of thrombin binding to aptamers, a class of compounds with intriguing pharmaceutical properties. Although these compounds anchor to protein using conservative patterns on its surface, the present analysis highlights some interesting peculiarities. Moreover, the impact of thrombin binding aptamers in the elucidation of the cross-talk between the two distant exosites is illustrated. Collectively, the data and the work here reviewed may provide insights into the design of novel thrombin inhibitors.     

Eruca sativa Might Influence the Growth,Survival under Simulated Gastrointestinal Conditions and Some Biological Features of Lactobacillus acidophilus,Lactobacillus plantarum and Lactobacillus rhamnosus Strains

The growth and viability of three Lactobacillus strains, Lactobacillus acidophilus, Lactobacillus plantarum and Lactobacillus rhamnosus, after their passage through simulated gastric and pancreatic juices were studied as a function of their presence in the growth medium of rocket salad (Eruca sativa). The presence of E. sativa affected some of the biological properties of the strains. For example, L. acidophilus and L. plantarum worked more efficiently in the presence of E. sativa, increasing not only the antioxidant activity of the medium, but also their own antioxidant power and antimicrobial activity; L. rhamnosus was not affected in the same manner. Overall, the presence of vegetables might help to boost, in specific cases, some of the characteristics of lactobacilli, including antioxidant and antimicrobial power.     

Microsurgery and changes in the testicular and epididymal production of spermatozoa

The researchers studied a group of azoospermic patients with obstructions of the seminal canals and a group of oligoasthenospermic patients suffering from varicocele in order to analyze the factors that influence the success of surgery aimed at recovering fertility. In the 46 patients suffering from obstructions of the deferent duct and the extremity of the epididymis, the time factor proved decisive if the obstruction lasted longer than 6 years: in this case, damage to the seminiferous tubules is not reversible. With obstructions dating back less than 4 years, the causes and the location of the obstruction are more incisive. Success was achieved in 100% of vasectomy cases and in 37.5% of epididymal-deferential anastomoses. In research literature, the superiority of microsurgery for treating these types of pathologies is taken for granted. In patients affected by oligoasthenospermia the effectiveness of laparoscopic ligation of the spermatic veins was compared to that of the Belgrano I technique. Of the 30 patients with bilateral varicocele and oligoasthenospermia dating back less than 4 years, 73.3% of the 15 patients operated on using the Belgrano 1 technique experienced sperm normalization; in the 15 cases operated on using laparoscopic ligation of the spermatic canals, normalization was much less frequent. Seventy-five percent of another group of 40 patients whose infertility did not have a duration of longer than 4 years and were operated on using microsurgery techniques were normalized. The percentage of the 60 oligoasthenospermic patients for longer than 6 years normalized was 16.6%.     

Loss of motor units in Alzheimer's disease

Little attention has been paid in the literature to the state of the peripheral nervous system (PNS) in Alzheimer's disease (AD). We conducted a comprehensive electrophysiological study in 15 AD patients looking for functional abnormalities within their PNSs. A reduction of the number of functioning motor units (MU) was found in the thenar and soleus muscles of most of these patients without enlargement of the remaining MUs territories, while the motor and sensory conduction velocities of the peripheral nerves were preserved. These results suggest dysfunction of the spinal motoneurones in patients afflicted with this condition.