Typifications of Linnaean names in the genus Centaurea and Serratula (Asteraceae)

The typification of three Linnaean names in the genus Centaurea and one in Serratula (Asteraceae): C. lippii (syn. Volutaria lippii), C. muricata (Volutaria muricata), C. repens (Rhaponticum repens) and S. babylonica (Centaurea babylonica), is discussed. Designations of nomenclatural types based on the consultation of Linnaeus's original material and the literature cited in the respective protologues are proposed. Three names are lectotypified using specimens from both Linnaeus herbarium at LINN and the illustrations from Isnard and Dodoëns. Furthermore, a neotype is designated for Serratula babylonica from a specimen at LINN.     

Comparative population genetic structure of redbelly tilapia (Coptodon zillii (Gervais, 1848)) from three different aquatic habitats in Egypt

Recently, tilapia have become increasingly important in aquaculture and fisheries worldwide. They are one of the major protein sources in many African countries and are helping to combat malnutrition. Therefore, maintenance and conservation genetics of wild populations of tilapia are of great significance. In this study, we report the population genetic structure and genetic diversity of the redbelly tilapia (Coptodon zillii) in three different Egyptian aquatic environments: brackish (Lake Idku), marine (Al‐Max Bay), and freshwater (Lake Nasser). The habitat differences, environmental factors, and harvesting pressures are the main characteristics of the sampling sites. Three mitochondrial DNA markers (COI: cytochrome oxidase subunit I; the D‐loop; CYTB: cytochrome b) were used to assess population structure differences among the three populations. The population at Lake Nasser presented the highest genetic diversity (H_d = 0.8116, H = 6), and the marine population of Al‐Max Bay the lowest (H_d = 0.2391, H = 4) of the combined sequences. In addition, the phylogenetic haplotype network showed private haplotypes in each environmental habitat. Results presented here will be useful in aquaculture to introduce the appropriate broodstock for future aquaculture strategies of C. zillii. In addition, evidence of population structure may contribute to the management of tilapia fisheries in Egyptian waters.     

Disuse and functional overload induced by tooth extraction alters neuromuscular morphology in C57BL/6J mice.

The effects of functional disuse and overload on the morphology of neuromuscular junctions (NMJ) in masseter muscles of 8 month old C57BL/6J mice were studied. In order to stimulate disuse caused by tooth loss, teeth were extracted from one upper quadrant of 10 mice. The side where teeth were removed was functionally disused (D), since occlusion could not be achieved. Similarly, the intact contralateral (CL) side experienced overload. Morphological measurements were taken of zinc iodide osmium (ZIO)-stained NMJs from control animals, and treated animals at 7 days (7D) and 4 months (4M) post-extraction. Data was analyzed with repeated measures multivariate analysis of covariance (MANCOVA). Test animals did not lose weight, which indicated that sufficient food was consumed after tooth extraction. Fiber diameters from the 7D group were smaller than the controls, while those from the 4M animals were larger. In both the 7D and 4M animals, the CL fibers were larger than the D fibers. There was a trend towards larger NMJs in the 4M animals than in control animals of the same age. NMJs from the CL side of the 4M animals had 14% larger nerve terminal areas (p<0. 1), while on the 4M D side they were 6% larger (p<0.10). NMJs from the 4M D group had 5% longer nerve terminals (p<0.07), while the 4M CL NMJs were 6% longer (p<0.05). NMJs from the D side of the 7D animals were 5% smaller in area while on the CL side they were 11% smaller (p<0.1). Nerve terminals in 7D animals were 6% longer (p<0.05) than in controls. Changes in NMJ morphology following tooth extraction were probably due to differences in degeneration -regeneration of nerve terminals. Acute disuse and overload probably produced greater nerve terminal retraction, whereas chronic changes consisted of a recovery characterized by NMJ plasticity similar to that observed in exercise, disuse and aging studies.     

In vitro free radical scavenging activity of hepatic metallothionein induced in an Indian freshwater fish, Channa punctata Bloch

Mammalian metallothioneins (MT) have been reported to scavenge free radicals. There is no experimental evidence to show that fish MT has a similar property. In the present study cadmium-induced MT (Cd-MT) from the liver of an Indian freshwater fish Channa punctata Bloch was investigated for its free radical scavenging activity using three different in vitro assays. Exposure to cadmium chloride (0.2 mg/kg body weight; three doses on alternate days) resulted in a marked induction of Cd-MT in liver. Only a single isoform of Cd-MT was found to be induced. Molecular weight of Cd-MT was found to be 14 kDa as deduced by SDS-PAGE analysis. The purified Cd-MT effectively scavenged the following free radicals: superoxide radical (O2*-), 2,2'-azinobis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS*+) and 1,1-diphenyl-picrylhydrazyl radical (DPPH*). The radical scavenging effect was found to be concentration-dependent. Also, the purified MT exhibited an inhibitory effect on ferric nitrilotriacetate (Fe-NTA) induced oxidative DNA damage in vitro. The cysteine residues of MT are proposed to be the main candidate for its radical scavenging activity. Findings of the present study strongly suggest a free radical scavenging role for fish MT. Present study adds to the little existing knowledge about fish MT and its possible biological functions.     

Uric acid mediates photodynamic inactivation of caprine alpha-2-macroglobulin

Uric acid (2,6,8 trioxopurine), the end product of purine metabolism in mammalian systems, has shown a wide range of antioxidant properties including scavenging of hydroxyl radical and singlet oxygen. In this study we show that in the presence of visible light, uric acid disrupted caprine alpha-2-macroglobulin (α₂M) structure and antiproteolytic function in vitro. Proteinase cleaves the bait region of caprine inhibitor inducing major conformational changes and entrapping the enzyme within its molecular cage. In contrast to native α₂M, modified antiproteinase lost half of its antiproteolytic potential within 4 hours of uric acid exposure. The changes in uv-absorption spectra of the treated protein suggested possible spatial rearrangement of subunits or conformational change. Analysis of the mechanism by which α₂M was inactivated revealed that the process was dependent on generation of superoxide anion and hydrogen peroxide. Our findings suggest that antiproteolytic activity of caprine α₂M could be compromised via oxidative modification mediated by uric acid. Moreover, low concentrations of α₂M were found to stimulate superoxide production by some unknown mechanism.     

The interactive effect of elevated temperature on deltamethrin-induced biochemical stress responses in Channa punctata Bloch

There are reports showing interactive effect of environmental factors with the toxic outcome of chemicals. We studied the interactive effect of elevated temperature as an abiotic stressor on deltamethrin-induced biochemical stress responses in a freshwater fish, Channa punctata Bloch. Heat stress (∼12 °C above ambient temperature for 3 h) and pesticide exposure (deltamethrin 0.75 ppb for 48 h) showed significant induction of heat shock protein-70 (HSP70) in liver, kidney and gills of fishes. Elevated temperature when followed by deltamethrin exposure showed synergistic effect showing a high level of HSP70 in liver and gills whereas response in the kidney was opposite. On the contrary, when deltamethrin exposure followed the heat stress, no significant difference was observed. Protein carbonylation was found to be more pronounced in heat-stressed group compared with control fish group. A significant increase in lipid peroxidation (LPO) was observed in different tissues of fish exposed to either of the stressors. In the kidney of fish exposed to heat stress followed by deltamethrin, LPO was relatively lower as compared to other treatments. Thiols content such as reduced glutathione (GSH), total thiols (T-SH), non-protein thiols (NP-SH) and protein thiols (P-SH) showed no consistent pattern in different tissues. In deltamethrin-exposed group that was subsequently exposed to heat stress, the GSH content was higher in liver and lower in both kidney and gills when compared with other groups. Alteration in the activities of antioxidant enzymes such as catalase (CAT), glutathione S-transferase (GST), glutathione reductase (GR) and glutathione peroxidase (GPx) was also observed when fish were exposed to heat stress and/or deltamethrin. Our study demonstrated that heat stress modulated biochemical stress responses in fish showing a tissue specific pattern. This implies that fish has the capacity to elicit differential response to exposure to abiotic stressors in order to reduce the systemic magnitude of stress which may otherwise lead to severe dysfunction of vital tissues.     

Immune Response to Snake Envenoming and Treatment with Antivenom; Complement Activation,Cytokine Production and Mast Cell Degranulation

Background

Snake bite is one of the most neglected public health issues in poor rural communities worldwide. In addition to the clinical effects of envenoming, treatment with antivenom frequently causes serious adverse reactions, including hypersensitivity reactions (including anaphylaxis) and pyrogenic reactions. We aimed to investigate the immune responses to Sri Lankan snake envenoming (predominantly by Russell''s viper) and antivenom treatment.

Methodology/Principal Findings

Plasma concentrations of Interleukin (IL)-6, IL-10, tumor necrosis factor α (TNFα), soluble TNF receptor I (sTNFRI), anaphylatoxins (C3a, C4a, C5a; markers of complement activation), mast cell tryptase (MCT), and histamine were measured in 120 Sri Lankan snakebite victims, both before and after treatment with antivenom. Immune mediator concentrations were correlated with envenoming features and the severity of antivenom-induced reactions including anaphylaxis. Envenoming was associated with complement activation and increased cytokine concentrations prior to antivenom administration, which correlated with non-specific systemic symptoms of envenoming but not with coagulopathy or neurotoxicity. Typical hypersensitivity reactions to antivenom occurred in 77/120 patients (64%), satisfying criteria for a diagnosis of anaphylaxis in 57/120 (48%). Pyrogenic reactions were observed in 32/120 patients (27%). All patients had further elevations in cytokine concentrations, but not complement activation, after the administration of antivenom, whether a reaction was noted to occur or not. Patients with anaphylaxis had significantly elevated concentrations of MCT and histamine.

Conclusions/Significance

We have demonstrated that Sri Lankan snake envenoming is characterized by significant complement activation and release of inflammatory mediators. Antivenom treatment further enhances the release of inflammatory mediators in all patients, with anaphylactic reactions characterised by high levels of mast cell degranulation but not further complement activation. Anaphylaxis is probably triggered by non allergen-specific activation of mast cells and may be related to the quality of available antivenom preparations, as well as a priming effect from the immune response to the venom itself.     

Progesterone and vitamin D: Improvement after traumatic brain injury in middle-aged rats

Progesterone (PROG) and vitamin D hormone (VDH) have both shown promise in treating traumatic brain injury (TBI). Both modulate apoptosis, inflammation, oxidative stress, and excitotoxicity. We investigated whether 21 days of VDH deficiency would alter cognitive behavior after TBI and whether combined PROG and VDH would improve behavioral and morphological outcomes more than either hormone alone in VDH-deficient middle-aged rats given bilateral contusions of the medial frontal cortex. PROG (16 mg/kg) and VDH (5 μg/kg) were injected intraperitoneally 1 h post-injury. Eight additional doses of PROG were injected subcutaneously over 7 days post-injury. VDH deficiency itself did not significantly reduce baseline behavioral functions or aggravate impaired cognitive outcomes. Combination therapy showed moderate improvement in preserving spatial and reference memory but was not significantly better than PROG monotherapy. However, combination therapy significantly reduced neuronal loss and the proliferation of reactive astrocytes, and showed better efficacy compared to VDH or PROG alone in preventing MAP-2 degradation. VDH + PROG combination therapy may attenuate some of the potential long-term, subtle, pathophysiological consequences of brain injury in older subjects.     

Effect of lemon essential oil on the developmental stages of Trialeurodes vaporariorum West (Homoptera: Aleyrodidae)

Trialeurodes vaporariorum (Homoptera: Aleyrodidae), is a destructive pest of many ornamental and greenhouse crops throughout the world. In this research, effect of essential oil derived from lemon peel, Citrus aurantifolia (Hook.) on mortality of eggs, first-instar nymphs and on adult oviposition of T. vaporariorum (Westwood) was determined under laboratory conditions. Analysis of Citrus aurantifolia essential oil used for insect fumigation by phase gas chromatography revealed the presence of 16 compounds including Limonene (56.6%), β-pinene (16.3%) and α-terpineol (11.3%). Five concentrations of essential oil – 0.002, 0.004, 0.008, 0.016 and 0.032 (μl/ml) – were applied in fumigant toxicity experiments. Greater mortality was observed with increasing dose of essential oil. First-instar nymphs were more sensitive to essential oil treatments compared with eggs and adults that reduced the survival rate of T. vaporariorum by 58, 70 and 56% after treatment of eggs, nymphs and adult, respectively. Based on this study, essential oil derived from C. aurantifolia could be used as an effective and environmentally sustainable bioinsecticide for the control of T. vaporariorum.