Phytochemicals from the stem wood of Sorbus lanata (D. Don.) Schauer

Three new phenolic compounds, sorlanin (4-(3-(hydroxymethyl)-5-methoxy-7-phenyl-2,3-dihydrobenzo[b][1,4]dioxin-2-yl)-2-methoxyphenol, 1), sorbanin (2-((3,5-dimethoxy-[1,1′-biphenyl]-4-yl)oxy)-1-(4-hydroxy-3-methoxyphenyl)propane-1,3-diol, 2) and sorbalanin (4-(3-(hydroxymethyl)-5,6-dimethoxy-2,3-dihydrobenzo[b][1,4]dioxino[2,3-g]benzofuran-2-yl)-2-methoxyphenol, 3), together with eight known compounds, polystachyol (4), isolariciresinol (5), dihydrodehydrodiconiferyl alcohol (6), tuberculatin (7), ovafolinin E (8), aucuparin (9), 2′-methoxyaucuparin (10), and tetracosyl-3-(3,4-dihydroxyphenyl)acrylate (11), were isolated from Sorbus lanata. The structures of these phytoconstituents were elucidated through extensive spectroscopic techniques, including UV, IR, 1D and 2D NMR, ESI-MS and HRESI-MS experiments. All the compounds except 9 and 10 were isolated for the first time from the genus Sorbus. The isolated compounds were also tested in DPPH radical scavenging reaction where compounds 6, 7, 10 and 11 showed significant activities with IC₅₀ values of 9.2, 11.7, 23.0 and 33.7 μM, respectively.     

A Critical Role for ISGylation,Ubiquitination and,SUMOylation in Brain Damage: Implications for Neuroprotection

Neurochemical Research - Post-translational modification (PTMs) of proteins by ubiquitin and ubiquitin-like modifiers such as interferon-stimulated gene 15 (ISG15) and small ubiquitin-related...     

Absolute Configuration of Oplopanone Derivatives From Serphidium stenocephalum: ECD Spectra of Acyclic Ketones With Front‐Octant Contributions

The electronic circular dichroism (ECD) spectra of two sesquiterpenoids ( 1 and 2 ) related to oplopanone, obtained from a methanolic extract of the plant Serphidium stenocephalum (Artemisia stenocephala), were measured and reproduced by means of time‐dependent density functional theory (TDDFT) calculations, establishing their absolute configuration. The application of ketone octant rule for carbonyl n‐π* ECD band to compounds 1 and 2 , which include an acyclic carbonyl group, was critically assessed. The peculiar oplopanone skeleton makes a straightforward application of the octant rule impossible, because of the uncertainty related to the shape of the so‐called third nodal surface separating front and back octants. The various group contributions to the carbonyl n‐π* ECD band were estimated with TDDFT calculations on selected molecular models obtained by consecutive dissections from 1 . Chirality 26:39–43, 2013. © 2013 Wiley Periodicals, Inc.     

Possible role of metal ionophore against zinc induced cognitive dysfunction in <Emphasis Type=SmallCaps>d-</Emphasis>galactose senescent mice

Metal ionophores are considered as potential anti-dementia agents, and some are currently undergoing clinical trials. Many metals are known to accumulate and distribute abnormally in the aging brain. Alterations in zinc metal homeostasis in the glutaminergic synapse could contribute to ageing and the pathophysiology of Alzheimer’s disease (AD). The present study was designed to investigate the effect of metal ionophores on long term administration of zinc in D-galactose induced senescent mice. The ageing model was established by combined administration of zinc and D-galactose to mice for 6 weeks. A novel metal ionophore, PBT-2 was given daily to zinc-induced d-galactose senescent mice. The cognitive behaviour of mice was monitored using the Morris Water Maze. The anti-oxidant status and amyloidogenic activity in the ageing mouse was measured by determining mito-oxidative parameters and deposition of amyloid β (Aβ) in the brain. Systemic administration of both zinc and D-galactose significantly produced memory deficits, mito-oxidative damage, heightened acetylcholinesterase enzymatic activity and deposition of amyloid-β. Treatment with PBT-2 significantly improved behavioural deficits, biochemical profiles, cellular damage, and curbed the deposition of APP in zinc-induced senescent mice. These findings suggest that PBT-2, acting as a metal protein attenuating compound, may be helpful in the prevention of AD or alleviation of ageing.     

Relative regeneration proficiency ofArabidopsis thaliana ecotypes

We have compared regeneration proficiency for cultured explants from different tissues of different ecotypes ofArabidopsis thaliana. Proficiency varies widely with both tissue and ecotype, and is highest when the flux of light during regeneration is low. Analysis of F1 hybrids suggests that high proficiency is dominant to low proficiency.     

Line thinning enhances diversity of Coleoptera in overstocked Cryptomeria japonica plantations in central Japan

We evaluated the effectiveness of line thinning, a new silvicultural technique, toward restoring diversity of Coleoptera in overstocked Cryptomeria japonica D. Don plantations in central Japan. We compared the abundance of some common Coleoptera families between line-thinned stands and adjacent unthinned stands in two plantations: low-elevation Sugi site (4 years since thinning) and high-elevation Kuchiotani site (6 years since thinning). Many bettle families comprising various functional groups such as plant feeders, wood borers, rotten wood feeders, root feeders, fungus feeders, dung feeders, and scavengers were more abundant in the line-thinned stands than in the unthinned stands. Furthermore, some important families were missing from the unthinned stands. There were strong positive relationships between Coleopteran abundance and understory vegetation. Our results suggest that line thinning may potentially increase biodiversity in overstocked C. japonica plantations by restoring important ecological processes such as food-web interactions (pollination, predation, herbivory, decomposition, parasitism, etc.), and habitat conditions.     

Loss of viability during freeze–thaw of intact and adherent human embryonic stem cells with conventional slow-cooling protocols is predominantly due to␣apoptosis rather than cellular necrosis

Summary A major challenge in the widespread application of human embryonic stem (hES) cells in clinical therapy and basic scientific research is the development of efficient cryopreservation protocols. Conventional slow-cooling protocols utilizing standard cryoprotectant concentrations i.e. 10% (v/v) DMSO, yield extremely low survival rates of <5% as reported by previous studies. This study characterized cell death within frozen–thawed hES colonies that were cryopreserved under standard conditions. Surprisingly, our results showed that immediately after post-thaw washing, the overwhelming majority of hES cells were viable (≈98%), as assessed by the trypan blue exclusion test. However, when the freshly-thawed hES colonies were incubated within a 37 °C incubator, there was observed to be a gradual reduction in cell viability over time. The kinetics of cell death was drastically slowed-down by keeping the freshly-thawed hES colonies at 4 °C, with >90% of cells remaining viable after 90 min of incubation at 4 °C. This effect was reversible upon re-exposing the cells to physiological temperature. The vast majority of low temperature-exposed hES colonies gradually underwent cell death upon incubation for a further 90 min at 37 °C. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end-labeling (TUNEL) assay confirmed apoptosis-induced nuclear DNA fragmentation in frozen–thawed hES cells after incubation at 37 °C for 90 min. Expression of active caspase-3 enzyme, which is another prominent marker of apoptosis, was confirmed by immunocytochemical staining, while transmission electron microscopy showed typical ultrastructural features of apoptosis such as chromatin condensation and margination to the nuclear membrane. Hence, our results demonstrated that apoptosis instead of cellular necrosis, is the major mechanism of the loss of viability of cryopreserved hES cells during freeze–thawing with conventional slow-cooling protocols.     

Antistaphylococcal and biofilm inhibitory activities of acetyl-11-keto-β-boswellic acid from <Emphasis Type="Italic">Boswellia serrata</Emphasis>

Background  

Boswellic acids are pentacyclic triterpenes, which are produced in plants belonging to the genus Boswellia. Boswellic acids appear in the resin exudates of the plant and it makes up 25-35% of the resin. β-boswellic acid, 11-keto-β-boswellic acid and acetyl-11-keto-β-boswellic acid have been implicated in apoptosis of cancer cells, particularly that of brain tumors and cells affected by leukemia or colon cancer. These molecules are also associated with potent antimicrobial activities. The present study describes the antimicrobial activities of boswellic acid molecules against 112 pathogenic bacterial isolates including ATCC strains. Acetyl-11-keto-β-boswellic acid (AKBA), which exhibited the most potent antibacterial activity, was further evaluated in time kill studies, postantibiotic effect (PAE) and biofilm susceptibility assay. The mechanism of action of AKBA was investigated by propidium iodide uptake, leakage of 260 and 280 nm absorbing material assays.     

Hemolin expression in the silk glands of Galleria mellonella in response to bacterial challenge and prior to cell disintegration

Hemolin, a member of the immunoglobulin protein superfamily, functions in Lepidoptera as an opsonin in defence against potential pathogens and seems to play a role in tissue morphogenesis. We show that hemolin gene is expressed in several organs of Galleria mellonella larvae, including the nervous system and the silk glands. The expression in the silk glands of the wandering larvae and their isolated abdomens is enhanced within 6 h after an injection of bacteria, lipopolysaccharides, or peptidoglycans. The magnitude of silk gland response to bacterial challenge is similar to that seen in the fat body. A profound rise of hemolin expression without bacterial inoculation occurs in the silk glands of isolated abdomens when they are induced to pupate by a topical application of 20-hydroxyecdysone (20E). The induction of pupation is associated with silk gland programming for disintegration by apoptosis and phagocytosis. Administration of a juvenile hormone agonist prevents pupation and abolishes the stimulatory 20E effect on the hemolin expression. Hemolin protein can be immunodetected in the silk glands as well as in the spun-out cocoon silk. The results suggest that silk glands are a component of the insect immune system and that hemolin may mark the apoptic cells for the elimination by hemocytes.