Synergism between plant extract and antimicrobial drugs used on Staphylococcus aureus diseases

Searches for substances with antimicrobial activity are frequent, and medicinal plants have been considered interesting by some researchers since they are frequently used in popular medicine as remedies for many infectious diseases. The aim of this study was to verify the synergism between 13 antimicrobial drugs and 8 plant extracts - "guaco" (Mikania glomerata), guava (Psidium guajava), clove (Syzygium aromaticum), garlic (Allium sativum), lemongrass (Cymbopogon citratus), ginger (Zingiber officinale), "carqueja" (Baccharis trimera), and mint (Mentha piperita) - against Staphylococcus aureus strains, and for this purpose, the disk method was the antimicrobial susceptibility test performed. Petri dishes were prepared with or without dilution of plant extracts at sub-inhibitory concentrations in Mueller-Hinton Agar (MHA), and the inhibitory zones were recorded in millimeters. In vitro anti-Staphylococcus aureus activities of the extracts were confirmed, and synergism was verified for all the extracts; clove, guava, and lemongrass presented the highest synergism rate with antimicrobial drugs, while ginger and garlic showed limited synergistic capacity.

Analitzador gràfic de xarxa en entorn GNU

Treball de fi de carrera d'enginyeria tècnica en informàtica de sistemes. El treball s'estructura en introducció, anàlisi, implementació, manual d'instal·lació, joc de proves... del treball. Aquest Treball Final de Carrera s'inclou dins de l'àrea de Xarxes deComputadors. Consisteix en la realització d'una aplicació gràfica en entornGNU que faci un anàlisi del tràfic d'una xarxa informàtica; això es coneix ambel nom de Sniffer.

Vector bionomics and malaria transmission in the Upper Orinoco River, Southern Venezuela

A longitudinal epidemiological and entomological study was carried out in Ocamo, Upper Orinoco River, between January 1994 and February 1995 to understand the dynamics of malaria transmission in this area. Malaria transmission occurs throughout the year with a peak in June at the beginning of the rainy season. The Annual Parasite Index was 1,279 per 1,000 populations at risk. Plasmodium falciparum infections accounted for 64% of all infections, P. vivax for 28%, and P. malariae for 4%. Mixed P. falciparum/P. vivax infections were diagnosed in 15 people representing 4% of total cases. Children under 10 years accounted for 58% of the cases; the risk for malaria in this age group was 77% higher than for those in the greater than 50 years age group. Anopheles darlingi was the predominant anopheline species landing on humans indoors with a biting peak between midnight and dawn. A significant positive correlation was found between malaria monthly incidence and mean number of An. darlingi caught. There was not a significant relationship between mean number of An. darlingi and rainfall or between incidence and rainfall. A total of 7295 anophelines were assayed by ELISA for detection of Plasmodium circumsporozoite (CS) protein. Only An. darlingi (55) was positive for CS proteins of P. falciparum (0.42%), P. malariae (0.25%), and P. vivax-247 (0.1%). The overall estimated entomological inoculation rate was 129 positive bites/person/year. The present study was the first longitudinal entomological and epidemiological study conducted in this area and set up the basic ground for subsequent intervention with insecticide-treated nets.

Anopheles darlingi bionomics and transmission of Plasmodium falciparum, Plasmodium vivax and Plasmodium malariae in Amerindian villages of the Upper-Maroni Amazonian forest, French Guiana

French Guiana is one of the areas in South America most affected by malaria and where the disease has become a serious public health problem. In spite of this situation, little recent entomological data are available from the main localities where the disease occurs, even though they are crucial for development of an effective vector control strategy. A longitudinal entomological survey was carried out from March 2000-February 2002 in three Amerindian villages, namely Twenké, Taluène and Cayodé, located in the Amazonian forest of the Upper-Maroni area, to assess anopheline mosquitoes and malaria transmission dynamics. Anopheles darlingi (Diptera: Culicidae) was the most abundant mosquito species caught during the study. This efficient American malaria vector was active the entire year, but showed an evident peak of abundance during the main rainfall season, from April-June, with an average human biting rate of 255.5 bites per person per night. Parity rates were homogeneous all year, indicating no significant seasonal variability in female survival rates. Estimated vectorial capacity indices were higher during the rainy season, even though the risk of transmission was present throughout the year (VCI > 1). A total of 14 An. darlingi were found infected with Plasmodium falciparum, Plasmodium vivax or Plasmodium malariae. The annual circumsporozoite indices were 0.15, 0.14 and 0.05, and the entomological inoculation rates were 22.8, 27.4 and 14.4 infected bites per person per year in Twenké, Taluène and Cayodé, respectively. An. darlingiwas endo-exophagic and rather exophilic in these localities. The species was collected throughout the night but was more aggressive between 21:30-03:30 h and after 05:30 h. Parity rates were homogeneous during the entire night. Impregnated hammock and/or bed nets, coupled with the use of mosquito repellents, as well as the early treatment of malarial cases, appear to be the most suitable tools for fighting malaria in these Amerindian villages since the spraying of residual insecticides is inefficient because of vector biology and the housing structure.

Biomedical nanoparticles modulate specific CD4(+) T cell stimulation by inhibition of antigen processing in dendritic cells

Understanding how nanoparticles may affect immune responses is an essential prerequisite to developing novel clinical applications. To investigate nanoparticle-dependent outcomes on immune responses, dendritic cells (DCs) were treated with model biomedical poly(vinylalcohol)-coated super-paramagnetic iron oxide nanoparticles (PVA-SPIONs). PVA-SPIONs uptake by human monocyte-derived DCs (MDDCs) was analyzed by flow cytometry (FACS) and advanced imaging techniques. Viability, activation, function, and stimulatory capacity of MDDCs were assessed by FACS and an in vitro CD4(+) T cell assay. PVA-SPION uptake was dose-dependent, decreased by lipopolysaccharide (LPS)-induced MDDC maturation at higher particle concentrations, and was inhibited by cytochalasin D pre-treatment. PVA-SPIONs did not alter surface marker expression (CD80, CD83, CD86, myeloid/plasmacytoid DC markers) or antigen-uptake, but decreased the capacity of MDDCs to process antigen, stimulate CD4(+) T cells, and induce cytokines. The decreased antigen processing and CD4(+) T cell stimulation capability of MDDCs following PVA-SPION treatment suggests that MDDCs may revert to a more functionally immature state following particle exposure.

Ecology of Haemagogus sp. and Sabethes sp. (Diptera: Culicidae) in relation to the microclimates of the Caxiuanã National Forest, Pará, Brazil

This study was conducted in a meteorological tower located in the Caxiuanã Forest (municipality of Melgaço, Pará, Brazil) with the aim of assessing the vertical stratification of species of Haemagogus and Sabethes, potential vectors of the yellow fever virus. To investigate the role of microclimates in mosquito stratification, bimonthly collections were conducted at ground level (0 m), 8 m, 16 m and 30 m (canopy level), with the aid of entomological nets and suction tubes, from July 2005-April 2006. A total of 25,498 mosquitoes were collected; specimens of Sabethes sp. and Haemagogus janthinomyswere found mostly at heights of 16 m and 30 m while Hg. leucocelaenus was most frequently observed at ground level. The largest number of vector species was collected during the rainiest months, but this difference between seasons was not statistically significant. However, the number of Hg. janthinomys was positively correlated with variations in temperature and relative humidity.

Antigenic heterogeneity of clones and subclones from human melanoma cell lines demonstrated by a panel of monoclonal antibodies and flow microfluorometry analysis.

Cells from two melanoma cell lines, Me43 and GLL-19, were cloned in methylcellulose cultures and 20 randomly selected colonies from each line were picked up by micromanipulation, expanded in liquid cultures, and considered as clones of the original cell lines. The antigenic cell surface phenotype of these clones defined by panel of 12 monoclonal antibodies (MAb) was analyzed by flow microfluorometry (FMF) using a fluorescence-activated cell sorter (FACS II) and compared with the known stable phenotype of the parent cell line. The antibody panel consisted of eight MAb against melanoma-associated antigens, two MAb against monomorphic determinants of HLA-DR (la) and HLA-ABC, respectively, one MAb against the common acute lymphoblastic leukemia antigen (CALLA) and one MAb against carcinoembryonic antigen used as control. A remarkable heterogeneity in terms of qualitative and quantitative expression of the cell surface antigens studied was observed among and within the different clones. The single-cell origin of the clones was assessed by comparing the clonogenic cell frequency, determined by limiting dilutions in microculture plates, with the cloning efficiency observed in Petri dishes. Both techniques using methylcellulose medium gave the same percentages of growing colonies. Cells from four Me43 clones were recloned in methylcellulose and the phenotype of five randomly selected subclones from each clone was analysed using the same panel of monoclonal antibodies. Each subclone also displayed heterogeneity with individual phenotypes different from that of the original clone and from the parental Me43 cell line. The antigen expression by individual cells in situ within clones was analyzed on frozen sections from colonies using the same panel of MAb and a biotin-avidin immunoperoxidase method. The results confirmed the marked heterogeneity of antigen expression within and among colonies, as indicated by the FMF analysis.

Sexually dimorphic melanin-based colour polymorphism, feather melanin content, and wing feather structure in the barn owl (Tyto alba)

Feathers confer protection against biophysical agents and determine flying ability. The geometry and arrangement of the barbs, together with the keratin and pigments deposited in the feathers, determine the mechanical stability of the vane, and its stiffness and resistance to abrasive agents. In colour-polymorphic species, individuals display alternative colour morphs, which can be associated with different foraging strategies. Each morph may therefore require specific flying abilities, and their feathers may be exposed to different abrasive agents. Feathers of differently coloured individuals may thus have a specific structure, and colour pigments may help resist abrasive agents and improve stiffness. We examined these predictions in the barn owl (Tyto alba), a species for which the ventral body side varies from white to dark reddish pheomelanic, and in the number and size of black spots located at the tip of the feathers. White and reddish birds show different foraging strategies, and the size of black feather spots is associated with several phenotypic attributes. We found that birds displaying a darker reddish coloration on the ventral body side deposit more melanin pigments in their remiges, which also have fewer barbs. This suggests that wear resistance increases with darkness, whereas feathers of lighter coloured birds may bend less easily. Accordingly, individuals displaying a lighter reddish coloration on the ventral body side, and those displaying larger black spots, displayed more black transverse bars on their remiges: as larger-spotted individuals are heavier and longer-winged birds also have more transverse bars, these bars may reduce feather bending when flying. We conclude that differently coloured individuals produce wing feathers of different strengths to adopt alternative behavioural and life history strategies

Mission control system for dam inspection with an AUV

This paper presents a complete control architecture that has been designed to fulfill predefined missions with an autonomous underwater vehicle (AUV). The control architecture has three levels of control: mission level, task level and vehicle level. The novelty of the work resides in the mission level, which is built with a Petri network that defines the sequence of tasks that are executed depending on the unpredictable situations that may occur. The task control system is composed of a set of active behaviours and a coordinator that selects the most appropriate vehicle action at each moment. The paper focuses on the design of the mission controller and its interaction with the task controller. Simulations, inspired on an industrial underwater inspection of a dam grate, show the effectiveness of the control architecture

Growth, cysts and kinetics of Borrelia garinii (Spirochaetales: Spirochaetacea) in different culture media

The aim of the present paper was to evaluate cyst formation and growth parameters of Borrelia garinii in a range of media differing in formulation and cost. A qualitative assessment of morphology and motility of B. garinii was conducted. All media were prepared aseptically and used in test tubes or Petri dishes. For each medium, the initial spirochete concentration was standardized to 10³ spirochets/mL. The following culture media were suitable to grow B. garinii: Barbour-Stoenner-Kelly, brain heart infusion and PMR. Growth was minimal at six weeks post-inoculation and maximum spirochete density was observed between 9-12 weeks. Often, the cultures developed cysts of different sizes, isolated or in groups, with a spiraled portion of variable sizes, mainly in unfavorable culture media. Brazilian Lyme disease-like illness, also known as Baggio-Yoshinari syndrome (BYS), is a new and interesting emerging tick-borne disease, caused by Borrelia burgdorferi sensu lato spirochetes, only during its cystic forms. It has been assumed that the peculiar clinical and laboratory features of BYS are consequential to the absence of a human sucker Ixodes ricinus complex tick at risk areas in Brazil, supporting the concept that the borrelia phenotypic expression pattern is modified as it is transmitted through the host.

Pregnancy and reproduction in autoimmune rheumatic diseases.

Despite evidence for the important role of oestrogens in the aetiology and pathophysiology of chronic immune/inflammatory diseases, the previous view of an unequivocal beneficial effect of oestrogens on RA compared with a detrimental effect on SLE has to be reconsidered. Likewise, the long-held belief that RA remits in the majority of pregnant patients has been challenged, and shows that only half of the patients experience significant improvement when objective disease activity measurements are applied. Pregnancies in patients with SLE are mostly successful when well planned and monitored interdisciplinarily, whereas a small proportion of women with APS still have adverse pregnancy outcomes in spite of the standard treatment. New prospective studies indicate better outcomes for pregnancies in women with rare diseases such as SSc and vasculitis. Fertility problems are not uncommon in patients with rheumatic disease and need to be considered in both genders. Necessary therapy, shortly before or during the pregnancy, demands taking into account the health of both mother and fetus. Long-term effects of drugs on offspring exposed in utero or during lactation is a new area under study as well as late effects of maternal rheumatic disease on children.

Can Wolbachia be used to control malaria?

Malaria is a mosquito-borne infectious disease caused by Plasmodium parasites transmitted by the infectious bite of Anopheles mosquitoes. Vector control of malaria has predominantly focused on targeting the adult mosquito through insecticides and bed nets. However, current vector control methods are often not sustainable for long periods so alternative methods are needed. A novel biocontrol approach for mosquito-borne diseases has recently been proposed, it uses maternally inherited endosymbiotic Wolbachia bacteria transinfected into mosquitoes in order to interfere with pathogen transmission. Transinfected Wolbachia strains in Aedes aegypti mosquitoes, the primary vector of dengue fever, directly inhibit pathogen replication, including Plasmodium gallinaceum, and also affect mosquito reproduction to allow Wolbachia to spread through mosquito populations. In addition, transient Wolbachia infections in Anopheles gambiae significantly reduce Plasmodium levels. Here we review the prospects of using a Wolbachia-based approach to reduce human malaria transmission through transinfection of Anopheles mosquitoes.

Collectio sermonum de dominicis, de festis et de sanctis, ad usum Fratrum Minorum.

« Sermo adaptabillis b. Laurentio... Dispersit, dedit pauperibus... Quia secundum b. Dionixium in De ecclesiastica Yerarchia... » (1-2) ; — « Sermo de assumptione b. Marie... Quid hoc audio de te... Quid nos tantilly... » (2v-3), suivi d'une note à l'usage des prédicateurs : « Nota quod ne sermo sit deffectuosus... » (3) ; — « Sermo de conceptione b. Marie. Que est ista que progreditur... Karissimi, predicator evangelicus, beatitudinis eterne preco... » (3v-4v) ; — « Sermo de quatuor festis principalibus b. Marie... Que est ista que progreditur... Verba ista sunt tocius curie celestis... » (4v-5v) ; — « Sermo de Purificatione. In mansuetudine suscipite... Secundum b. Gregorium, Mor. 23... » (6-7) ; — « Sermo de b. Francischo... Cujus est ymago hec et superscriptio... Secundum b. Gregorium, omelia 30... » (7v-8v) ; — « Sermo in dominica [in Quinquagesima]. Ecce ascendimus Jerosolimam... Karissimi, sicut scitis, finis est... » (9-10) ; — [Sermo in dominica IIa post Epiphaniam] « Tu servasti vinum bonum usque adhuc... In verbis istis spiritualiter intellectus... » (10-10v) ; — « Sermo de b. Francischo. Ad ymaginem similitudinis sue... Verba ista ad litteram scripta... » (11-12) ; — « Sermo de b. Johane Baptista. Magnus es tu et faciens mirabilia... Secundum Gregorium quia tute... » (12v-13) ; — « Sermo de angelis. Inmittit angelus Domini... Sanctus ille David, acceptus de ovibus... » (13v-14) ; — « In ascensione Domini. Exultavit ut gigas... Duo sunt inter cetera Christi misteria... » (14v-16) ; — « De asumpcione Domine nostre. Ad preceptum tuum elevabitur aquila... Quia, karissimi, Mater Domini... » [FRANCISCUS DE MAYRONIS] ; cf. éd. Bâle, 1498, f. CIV-CIIIV, avec variantes (16v-18) ; — « De Maria Magdalena. Permittuntur [sic pro : Remittuntur] tibi peccata tua... Sicut solent maximi principes... » [Idem], sermon abrégé ; cf. éd. cit., f. LXXXVIIIV-XCI (18-19v) ; — « De s. Johane Evangelista. Dillectus meus michi... Ostenditur b. Johannes prout inflamatus... » [Idem], résumé ; cf. éd. cit., f. XXIX-XXIXV (20) ; — « In festo apostolorum Petri et Pauli. Accepimus gratiam et apostolatum... Gloriosissimi christiane fidei religionis... » (20v-23v) ; — « Sermo de gratia divina acquirenda. Accepimus gratiam etc. Vivat, obsecro, anima mea ... quoniam... » (24) ; — « Accepimus gratiam etc. Restat ostendere via physionomica... » (24v-26) ; — « Sermo de beatitudine, sive gloria celesti, sive in festo Omnium sanctorum. Fons sapientie verbum Dei... Ecce ego sto prope fontem... In hoc festo precipue et anno... » (26-29) ; — « De nativitate Domine nostre. Egredietur virga de radice Jesse... Percutiet terram virga... Clementissimus pastor ovium... » (29v-32) ; — « Sermo de uno confessore pontifice. Rector fratrum et stabilimentum populi... Inter viros eximie sanctitatis... » (32v) ; — « De nativitate Domini. Transeamus usque Bethelem... Innocencius in quodam sermone de predicatione... » (34v-36) ; — « In die nativitatis Domini. Sol ortus est et humiles exaltati sunt... Beatus Augustinus, De Civitate Dei : Anima participacione... » (36-37v) ; — « Dominica infra octavas Nativitatis. Ecce positus est hic in ruinam... Secundum doctrinam Philosophi in diversis locis... » (38-38v) ; — « Dominica quarta in quadragesima. Sequebatur eum multitudo magna... Secundum Damascenum libro primo, capitulo XV°, diversitas actionum... » (39-40v) ; — « De Canane[a], dominica secunda [sic] in quadragesima [Feria 5a post dom. Ia in XLa]. Dimitte illam quia clamat... Si attendamus ordinem generacionis... » (41-42v) ; — « Dominica de Passione. Si veritatem dico vobis... Secundum sententiam Phylosophi primo Metaphysice... » (43-43v) ; — « In cena Domini. Hodie est rex et cras morietur... Omne agens ordinate prius inquirit... » (44-45) ; — « De resurectione. Hec dies quam fecit Dominus... Scilicet est ex dictis Philosophi in diversis locis... » (45v-47) ; — « Dominica in Quadragesima. Ecce nunc tempus acceptabile... Ut dicit Philosophus, secundo de Celo et mundo... » (47-48v) ; — « De b. Clara. Sicut lux meridiana clara est... Secundum Philosophum tertio Methaphysice, si res creatas... » (48v-49v) ; — « Sermo de Cruce. Vidit mulier quod bonum esset lignum... Sicut ex doctrina Philosophi primo Ethicorum... » (50-51) ; — « De s. Anthonio. Misit servum suum hora cene... Sicut in rebus naturalibus docet experiencia... » (51v-52v) ; — « De b. Johane Batista. Tu puer propheta Altissimi... Secundum doctrinam Hugonis in commento de angelica Jerarchia... » (53-54) ; — « De b. Bertholameo [sic]. Dedit illi contra inimicos potenciam... Racio docet et experiencia manifestat... » (54v-55) ; — « De b. Francischo. Amice, ascende superius... Dicit Philosophus quinto Physicorum quod motus... » (55v-56) ; — [De b. Bernardo] « Omnia parata sunt, venite ad nupcias... Sicut videmus in motu naturali... » (56v-57) ; — « De sacerdote novo. Vos elegit Dominus... Ut potest haberi ex dictis Dyonisii... » (57v-58v) ; — « De assumpcione Virginis gloriose. Elevetur tronus David super Israel... Videmus quod triplici racione aliqua corpora... » (58v-59v) ; — « De assumpcione Virginis. Veni de Libano sponsa mea... Secundum testimonium Scripturarum et humane consuetudinis... » (59v-61) ; — « De Trinitate. Tripliciter sol exurens montes... Secundum quod dicit Philosophus, tota nostra noticia... » (61-61v) ; — « De b. Francischo. Hic beatus in facto suo erit... Post doctrinam philosophorum et experienciam... » (62-62v) ; — [De b. Eligio] « Provideat rex virum sapientem... Secundum sententiam (secundum) sapientis primo Metaphysice . » (63-64) ; — « De resurrectione Domini. Tercia dies est hodie... Tripliciter alicujus rei non vise accipimus fidem certam... » (64-65) ; — «Stetit in medio discipulorum et dixit : Pax vobis... Ut dicit b. Augustinus undevicesimo de Civitate Dei... » (65v-67) ; — « De Omnibus sanctis... Gloriosa dicta sunt de te... Aperta est civitas... Doctore egregio Bernardo scilicet attestante... » (67-69) ; — « De b. Johane Batista. Hic venit in testimonium... Sicut potest probari ex dictis Philosophi et exemplis... » (69v-70) ; — « De b. Petro apostolo. Tu pasce populum meum Israel... Secundum sententiam Philosophi tertio Politicorum... » (70v-71) ; — « De assumpcione Virginis gloriose. Transibo in locum tabernaculi... Triplici ratione secundum philosophorum doctrinam aliqua moventur... » (71v-72v) ; — [De b. Francisco] « Adolescens, tibi dico surge... Consideranti sciderum revolucionem... » (73-74v) ; — [De s. Michaele] « Michael et angeli preliabantur... Sicut ex doctrina Phylosophi in pluribus locis patet... » (74v-76) ; — « De b. Nicholao. Petra fundebat michi rivos olei... Secundum philosophicam doctrinam, diversitas effectuum... » (76-77) ; — « In festo apostolorum Petri et Pauli. Fecit Deus duo luminaria magna... Secundum sententiam Philosophi secundo Methaphysice... » (77v-78) ; — « De b. Bertholameo. Vidi angelum fortem... Secundum dictum Philosophi, omnes transferentes... » (78v-79) ; — « Dominica in Quadragesima. Ductus est Jhesus in desertum... Sicut naturalium operationum multiplex experiencia... » (79v-80v) ; — « De s. Thoma apostolo. Ecce cognovi quoniam Deus meus es... Bernardus in sermone : Deus noverim me... » (81-81v) ; — « De sacerdote novo. Misit Dominus servum suum... Secundum quod dicit Philosophus primo Ethicorum, diversarum operationum... » (82-82bis) ; — « In purificatione Virginis. Parasti ante faciem omnium populorum... Si attendamus formationem rerum temporalium... » (82bisv-83v) ; — « De uno martire. Esto vir fortis, et prelia bella Domini... Secundum consuetudinem hominum... » (84-85) ; — « De festo Purificacionis. Lucerna splendens super candelabrum... Doctrina philosophorum et tradit... » (85v-86v) ; — « Feria quarta Cinerum. Cum jejunas unge caput tuum... Morum Philosophi doctrinam perlegens et attendens... » (87-88v) ; — « In quarta feria Cinerum. Cum jejunatis, nolite fieri sicut ypocrite... Sicut ex doctrina Philosophi primo Ethicorum potest colligi... » (88v-89v) ; — « In festo b. Lodovici [episcopi]. Surrexit rex de solio suo... Ut dicit Philosophus quarto Methaphysicorum... » (90-91v) ; — « De b. Jacobo. Vox tonitrui tui in rota... Secundum doctrinam philosophicam formarum naturalium... » (91v-92v) ; — [In festo Annunciationis] « Ecce concipies in utero... Secundum doctrinam Philosophi septimo de Animalibus, ad generationem... » (93-94) ; — « De s. Ludovico [episcopo]. Reposita est michi corona justitie... Secundum sententiam Philosophi secundo Phisicorum, omne agens... » (94-96).

Intracellular excision and reintegration dynamics of the ICEclc genomic island of Pseudomonas knackmussii sp. strain B13.

Genomic islands are DNA elements acquired by horizontal gene transfer that are common to a large number of bacterial genomes, which can contribute specific adaptive functions, e.g. virulence, metabolic capacities or antibiotic resistances. Some genomic islands are still self-transferable and display an intricate life-style, reminiscent of both bacteriophages and conjugative plasmids. Here we studied the dynamical process of genomic island excision and intracellular reintegration using the integrative and conjugative element ICEclc from Pseudomonas knackmussii B13 as model. By using self-transfer of ICEclc from strain B13 to Pseudomonas putida and Cupriavidus necator as recipients, we show that ICEclc can target a number of different tRNA(Gly) genes in a bacterial genome, but only those which carry the GCC anticodon. Two conditional traps were designed for ICEclc based on the attR sequence, and we could show that ICEclc will insert with different frequencies in such traps producing brightly fluorescent cells. Starting from clonal primary transconjugants we demonstrate that ICEclc is excising and reintegrating at detectable frequencies, even in the absence of recipient. Recombination site analysis provided evidence to explain the characteristics of a larger number of genomic island insertions observed in a variety of strains, including Bordetella petri, Pseudomonas aeruginosa and Burkholderia.

The behaviour of mosquitoes in relation to humans under holed bednets: the evidence from experimental huts

The physical integrity of bednets is a concern of national malaria control programs, as it is a key factor in determining the rate of replacement of bednets. It is largely assumed that increased numbers of holes will result in a loss of protection of sleepers from potentially infective bites. Experimental hut studies are valuable in understanding mosquito behaviour indoors, particularly as it relates to blood feeding and mortality. This review summarises findings from experimental hut studies, focusing on two issues: (i) the effect of different numbers or sizes of holes in bednets and (ii) feeding behaviour and mortality with holed nets as compared with unholed nets. As might be expected, increasing numbers and area of holes resulted in increased blood feeding by mosquitoes on sleepers. However, the presence of holes did not generally have a large effect on the mortality of mosquitoes. Successfully entering a holed mosquito net does not necessarily mean that mosquitoes spend less time in contact with the net, which could explain the lack in differences in mortality. Further behavioural studies are necessary to understand mosquito behaviour around nets and the importance of holed nets on malaria transmission.