Ovicidal and adulticidal activities of Cinnamomum zeylanicum bark essential oil compounds and related compounds against Pediculus humanus capitis (Anoplura: Pediculicidae)

The toxicity of cinnamon, Cinnamomum zeylanicum, bark essential oil compounds against eggs and adult females of human head louse, Pediculus humanus capitis, was examined using direct contact and vapour phase toxicity bioassays and compared with the lethal activity of their related compounds, benzyl alcohol, cinnamic acid, cinnamyl acetate, 4-hydroxybenzaldehyde and salicylaldehyde, as well as two widely used pediculicides, d-phenothrin and pyrethrum. In a filter-paper contact toxicity bioassay with female lice at 0.25 mg/cm², benzaldehyde was 29- and 27-fold more toxic than pyrethrum and d-phenothrin, respectively, as judged by median lethal time (LT₅₀) values. Salicylaldehyde was nine and eight times more active than pyrethrum and d-phenothrin, respectively. Pediculicidal activity of linalool was comparable with that of d-phenothrin and pyrethrum. Cinnamomum bark essential oil was slightly less effective than either d-phenothrin or pyrethrum. Benzyl alcohol and (E)-cinnamaldehyde exhibited moderate pediculicidal activity. After 24 h of exposure, no hatching was observed with 0.063 mg/cm² salicylaldehyde, 0.125 mg/cm² benzaldehyde, 0.5 mg/cm² Cinnamomum bark essential oil, 1.0 mg/cm² (E)-cinnamaldehyde, and 1.0 mg/cm² benzyl cinnamate. Little or no ovicidal activity was observed with d-phenothrin or pyrethrum. In vapour phase toxicity tests with female lice, benzaldehyde and salicylaldehyde were much more effective in closed containers than in open ones, indicating that the mode of delivery of these compounds was largely due to action in the vapour phase. Neither d-phenothrin nor pyrethrum exhibited fumigant toxicity. Cinnamomum bark essential oil and test compounds described merit further study as potential pediculicides or ovicides for the control of P. h. capitis.     

Antifungal activity of synthetic peptide derived from halocidin, antimicrobial peptide from the tunicate, Halocynthia aurantium

Halocidin is an antimicrobial peptide isolated from the hemocytes of the tunicate. Among the several known synthetic halocidin analogues, di-K19Hc has been previously confirmed to have the most profound antibacterial activity against antibiotic-resistant bacteria. This peptide has been considered to be an effective candidate for the development of a new type of antibiotic. In this study, we have assessed the antifungal activity of di-K19Hc, against a panel of fungi including several strains of Aspergillus and Candida. As a result, we determined that the MICs of di-K19Hc against six Candida albicans and two Aspergillus species were below 4 and 16 microg/ml, respectively, thereby indicating that di-K19Hc may be appropriate for the treatment of several fungal diseases. We also conducted an investigation into di-K19Hc's mode of action against Candida albicans. Our colony count assay showed that di-K19Hc killed C. albicans within 30s. Di-K19Hc bound to the surface of C. albicans via a specific interaction with beta-1,3-glucan, which is one of fungal cell wall components. Di-K19Hc also induced the formation of ion channels within the membrane of C. albicans, and eventually observed cell death, which was confirmed via measurements of the K+ released from C. albicans cells which had been treated with di-K19Hc, as well as by monitoring of the uptake of propidium iodide into the C. albicans cells. This membrane-attacking quality of di-K19Hc was also visualized via confocal laser and scanning electron microscopy.     

Stratégie cynégétique et mode de vie à l'Azilien ancien dans le Bassin parisien : les apports de l'exploitation des chevaux du Closeau (niveau inférieur ; Rueil-Malmaison, Hauts-de-Seine)

The Closeau's lower level (Rueil-Malmaison, Hauts-de-Seine) brought evidence of Early Azilian occupations, in which the horse were the main prey. This paper present the zooarchaeological results of the equid's processing, according to the occupation units 4 and 46. The horse acquisition show that chase-approach hunts were the tactic employed, by a single individual or some small bands. The equids hunts' repetition testify that such activities took place at different moments of the year, especially in autumn and at the end of winter-springtime. These data allow a better understanding of the reasons that can explain why all phases of the animal processing were found in the inside of the occupation structures. The consumption of horse's meat and offal seems to take place only partly in situ. The units 4 and 46 can be interpreted as hunting camps, periodically use par Early Azilian bands. Such function of the site may signify that the mobility of these bands could integrated some traits of logistical pattern to a certain extent, but until now their lifeway stay unclear without new discoveries.     

Solution structure of the phosphotyrosine binding (PTB) domain of human tensin2 protein in complex with deleted in liver cancer 1 (DLC1) peptide reveals a novel peptide binding mode

The protein deleted in liver cancer 1 (DLC1) interacts with the tensin family of focal adhesion proteins to play a role as a tumor suppressor in a wide spectrum of human cancers. This interaction has been proven to be crucial to the oncogenic inhibitory capacity and focal adhesion localization of DLC1. The phosphotyrosine binding (PTB) domain of tensin2 predominantly interacts with a novel site on DLC1, not the canonical NPXY motif. In this study, we characterized this interaction biochemically and determined the complex structure of tensin2 PTB domain with DLC1 peptide by NMR spectroscopy. Our HADDOCK-derived complex structure model elucidates the molecular mechanism by which tensin2 PTB domain recognizes DLC1 peptide and reveals a PTB-peptide binding mode that is unique in that peptide occupies the binding site opposite to the canonical NPXY motif interaction site with the peptide utilizing a non-canonical binding motif to bind in an extended conformation and that the N-terminal helix, which is unique to some Shc- and Dab-like PTB domains, is required for binding. Mutations of crucial residues defined for the PTB-DLC1 interaction affected the co-localization of DLC1 and tensin2 in cells and abolished DLC1-mediated growth suppression of hepatocellular carcinoma cells. This tensin2 PTB-DLC1 peptide complex with a novel binding mode extends the versatile binding repertoire of the PTB domains in mediating diverse cellular signaling pathways as well as provides a molecular and structural basis for better understanding the tumor-suppressive activity of DLC1 and tensin2.     

A model-structure of a periplasm-facing state of the NhaA antiporter suggests the molecular underpinnings of pH-induced conformational changes

The Escherichia coli NhaA antiporter couples the transport of H(+) and Na(+) (or Li(+)) ions to maintain the proper pH range and Na(+) concentration in cells. A crystal structure of NhaA, solved at pH 4, comprises 12 transmembrane helices (TMs), arranged in two domains, with a large cytoplasm-facing funnel and a smaller periplasm-facing funnel. NhaA undergoes conformational changes, e.g. after pH elevation to alkaline ranges, and we used two computational approaches to explore them. On the basis of pseudo-symmetric features of the crystal structure, we predicted the structural architecture of an alternate, periplasm-facing state. In contrast to the crystal structure, the model presents a closed cytoplasmic funnel, and a periplasmic funnel of greater volume. To examine the transporter functional direction of motion, we conducted elastic network analysis of the crystal structure and detected two main normal modes of motion. Notably, both analyses predicted similar trends of conformational changes, consisting of an overall rotational motion of the two domains around a putative symmetry axis at the funnel centers, perpendicular to the membrane plane. This motion, along with conformational changes within specific helices, resulted in closure at the cytoplasmic end and opening at the periplasmic end. Cross-linking experiments, performed between segments on opposite sides of the cytoplasmic funnel, revealed pH-dependent interactions consistent with the proposed conformational changes. We suggest that the model-structure and predicted motion represent alkaline pH-induced conformational changes, mediated by a cluster of evolutionarily conserved, titratable residues, at the cytoplasmic ends of TMs II, V, and IX.     

Novel whole-cell Reporter Assay for Stress-Based Classification of Antibacterial Compounds Produced by Locally Isolated Bacillus spp.

Reporter bacteria are beneficial for the rapid and sensitive screening of cultures producing peptide antibiotics, which can be an addition or alternative to the established antibiotics. This study was carried out to validate the usability of specific reporter strains for the target mediated identification of antibiotics produced by native Bacillus spp. isolated from different food sources. During preliminary classification, cell wall stress causing Bacillus isolates were screened by using reporter strain Bacillus subtilis BSF2470. The isolates which induced cell wall stress were further characterized for their specific mode of action by using other B. subtilis reporter strains (TMB 488, TMB 299 and TMB 279). The isolate B. licheniformis N12 was found to produce bacitracin confirmed by the response to reporter strain B. subtilis TMB 279 and by putative identification of bacitracin biosynthetic loci. The other isolate B. subtilis EC1 also induced B. subtilis TMB 279, but does not possess the bacitracin gene cluster indicating that it can be a novel, bacitracin like antibiotic. The different but related subsets of peptide antibiotics that bind the pyrophosphate moiety of the lipid carrier of cell wall biosynthesis can be identified using this whole cell based reporter strains.     

医学微生物学双语教学研究

实施双语教学是适应我国高等教育国际化趋势的发展需要。结合本校实际, 从采用英文原版教材进行医学微生物学双语教学必要性入手, 对医学微生物学双语教学方式、教学评价、教学效果等进行了探讨, 为我校双语教学模式的选择应用提供了一定的依据。     

Early human dispersal at the western edge of the Eastern European plain: Data from Ukraine

The current state of research on Lower Palaeolithic sites in Ukraine within its 1991 borders is the focus of this paper. Over the last 10–15 years, many new sites have been discovered in different parts of the eastern European area of the country, reassessed some old materials. In the central European region of the country, in the Ukrainian Transcarpathia, important new stratified Lower Palaeolithic sites have also been found. The current Ukrainian Lower Palaeolithic records demonstrate hominin presence in mountainous areas (Carpathians, Crimea) and the valleys of all major rivers, namely the Dniester, Southern Buh, Dnieper and Severskiy Donets. The article presents a brief review of the main currently known Lower Palaeolithic assemblages. Available geological, geomorphological, biostratigraphical data and ESR dates allow defining their age between 1.2 and 0.4 Myг; sites correlate with few warm phases between MIS 35 and MIS 11. Earlier sites, very tentatively dated at around 2 Myг, gravitate towards the seashore and mountainous areas. Later sites witness steady, though not continuous, colonisation of East European plain fringe areas. The main regularities of geographical setting, chronology, morphological and technological characteristics of assemblages of the Lower Palaeolithic sites of the Western segment of the East European plain are characterised. Typologically, industries are mainly characterised as belonging to Mode I. Core-and-flake industries survives to the Holsteinian. Essential difficulties in lithic raw materials supply could probably be a reason for the rise of a peculiar pattern of technological behaviour that involved mainly bipolar knapping and widely applied trimming technique of shaping the working edges of tools. Some signals of probable population movements penetrated the territory of Ukraine by the Asia Minor “western” trajectory and by Caucasian “eastern” way are revealed.     

La grotte de Santa Ana (Cáceres, Espagne) et l'évolution technologique au Pléistocène dans la Péninsule ibérique

The excavations carried out in the cave of Santa Ana (Cáceres, Spain), cave of the karstic network of the “Calerizo” of Cáceres, enabled us to know the existence, in stratigraphy, of the three lito-techniques modes which characterize the industrial development of lower and middle Pleistocene in the Iberian Peninsula. On standby of new research, the results obtained until now permit us two work out a diachronic assumption of technical evolution. In the Iberian Peninsula, there are only two karstic systems where we can fallow this technological development; one is the “Sierra de Atapuerca” (Burgos) and the other is the “Calerizo de Cáceres” (Cáceres).     

Animal xenodiversity in Italian inland waters: distribution, modes of arrival, and pathways

The paper provides a list of the non-indigenous animal species occurring today in Italian inland waters. Xenodiversity was found to amount to 112 species (64 invertebrates and 48 vertebrates), which contribute for about 2% to the inland-water fauna in Italy. Northern and central regions are most affected, and Asia, North America, and the rest of Europe are the main donor continents. The large majority of non-indigenous species entered Italy as a direct or indirect effect of human intervention. A difference between invertebrates and vertebrates was found for their mode of arrival (unintentional for invertebrates and intentional for vertebrates). Accidental transport, in association with both fish (for aquaculture or stock enhancement) and crops, has been the main vector of invertebrate introductions, whereas vertebrates were mostly released for stocking purposes. Overall stock enhancement (47.92%) and culture (37.5%) prevailed over the other pathways. Seventeen and 7 species of our list are included among the 100 worst invasive species of Europe (DAISIE) and of the world (IUCN), respectively. For some (but not all) non-indigenous species recorded in Italy the multilevel impact exerted on the recipient communities and ecosystems is known, even if rarely quantified, but knowledge on their chronic impact is still missing. Additional research is needed to provide criteria for prioritizing intervention against well established invaders and identify which new potential invader should be targeted as “unwanted”.