bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of deltamethrin‐impregnated bednets and curtains against phlebotomine sandflies in Valle del Cauca, Colombia
Authors: ALEXANDER B. , USMA M. C. , CADENA H. , QUESADA B. L. , SOLARTE Y. , ROA W. , TRAVI B. L. 
Published: March 2008

Abstract. The effectiveness of bednets and curtains (nylon mesh 64 per cm2) impregnated with deltamethrin at 26 mg a.i./m2 in reducing the biting nuisance caused by three phlebotomine sandfly species: Lutzomyia columbiana, Lu. lichyi and the predominant Lu. youngi (Diptera: Psychodidae), was evaluated at La Guaira, a rural settlement in Valle de Cauca near Cali, Colombia.Pairs of volunteers collected sandflies under impregnated bednets, in rooms protected by impregnated curtains or in unprotected rooms in a randomized matched design. Collections were made in three houses per night on three consecutive nights, so that each house was sampled under each of the three treatments. This routine was repeated at 2‐week intervals for 6 months. There was no significant difference between the overall numbers of sandflies collected in rooms with or without impregnated curtains. Only 0.14 sandflies/man‐hour were caught on human bait under impregnated bednets, significantly fewer than the numbers collected on human bait outside the nets in the same room (1.91) or in unprotected rooms (3.29).In a second set of experiments carried out in La Guaira and the neighbouring community of Jiguales, the effect of deltamethrin impregnation was evaluated by comparing numbers of sandflies collected on human bait under treated and untreated nets. Significantly fewer were collected under the impregnated nets (0.25 v. 0.69/man‐hour). Wild‐caught female Lu. youngi exposed to treated netting for 2 min in the laboratory all died with 24 h. The impact of deltamethrin‐impregnated bednets was considered to be useful against Lu. youngi and other potential vectors of leishmaniasis in such communities.
Comparison of different insecticides and fabrics for anti‐mosquito bednets and curtains
Authors: CURTIS C. F. , MYAMBA J. , WILKES T. J. 
Published: March 2008

Abstract. Various formulations of six insecticides (a carbamate and five pyrethroids), were impregnated into bednets and curtains made from cotton, polyester, polyethylene or polypropylene fabric. For bioassays of insecticidal efficacy, female Anopheles gambiae mosquitoes were made to walk on the fabrics for 3 min and mortality was scored after 24 h. The main concentrations tested were: bendiocarb 400 mg/m2, cyfluthrin 30–50 mg/m2, deltamethrin 15–25 mg/m2, etofenprox 200 mg/m2, lambda‐cyhalothrin 5–15 mg/m2 and permethrin 200–500 mg/m2. Field trials in Tanzania used experimental huts (fitted with verandah traps) entered by wild free‐flying Anopheles gambiae, An. funestus and Culex quinquefasciatus mosquitoes.Results of testing the impregnated fabrics in experimental huts showed better personal protection provided by bednets than by curtains. Permethrin cis:trans isomer ratios 25:75 and 40:60 were equally effective, and the permethrin rate of 200 mg/m2 performed as well as 500 mg/m2. Bioassay data emphasized the prolonged insecticidal efficacy of lambda‐cyhalothrin deposits, except on polyethylene netting. Most of the impregnated nets (including the ‘Olyset’ net with permethrin incorporated during manufacture of the polyethylene fibre) and an untreated intact net performed well in preventing both Anopheles and Culex mosquitoes from feeding on people using them overnight in the experimental huts. Anopheles showed high mortality rates in response to pyrethroid‐treated nets, but only bendiocarb treated curtains killed many Culex. Holed nets treated with either cyfluthrin (5 EW formulation applied at the rate of 50 mg a.i./m2) or lambda‐cyhalothrin (2.5 CS formulation at 10 mg a.i./m2) performed well after 15 months of domestic use. Treatment with deltamethrin SC or lambda‐cyhalothrin CS at the very low rate of 3 mg/m2 gave good results, including after washing and re‐treatment.
Density, survival and dispersal of Anopheles gambiae complex mosquitoes in a West African Sudan savanna village
Authors: COSTANTINI CARLO , LI SONG‐GANG , TORRE ALESSANDRA DELLA , SAGNON N'FALE , COLUZZI MARIO , TAYLOR CHARLES E. 
Published: March 2008

Abstract. To obtain information on adult populations of Afrotropical malaria vector mosquitoes, mark‐release‐recapture experiments were performed with Anopheles females collected from indoor resting‐sites in a savanna area near Ouagadougou, Burkina Faso, during September 1991 and 1992. Results were used to estimate the absolute population densities, daily survival rates, and dispersal parameters of malaria vectors in that area.In 1991 a total of 7260 female Anopheles were marked and released, of which 106 were recaptured in the release village and 6 in the neighbouring villages, a total recapture rate of 1.5%. The following year 13, 854 female Anopheles were released and 116 recaptured in Goundri and 8 in the neighbouring villages, a total recapture rate of 0.9%. Recaptures were found in three of eight villages near Goundri. Nearly all of the recaptured mosquitoes were An.gambiae s.l. Of these, molecular determination revealed that An.gambiae s.s. and An.arabiensis were present in a ratio of ‐2:3.Two simple random models of dispersal were simulated and the parameters of the models determined by searching for the least‐squared fit between simulated and observed distributions. The mean distance moved by individual mosquitoes, estimated in this way, ranged 350–650 m day‐1, depending on die model and the year considered. Population densities were estimated using the Lincoln Index, Fisher‐Ford and Jolly's methods. The estimates of population size had high standard errors and were not particularly consistent. A ‘consensus’ value of 150,000–350,000 mosquitoes is believed to apply for ht An.gambiae s.l. female population. Survival was estimated to be 80–88% per day.
Effect of fenthion treatment on larval densities of insecticide‐resistant Culex quinquefasciatus in an urban area of Sri Lanka
Authors: PEIRIS H. T. R. , HEMINGWAY J. 
Published: March 2008

Abstract. In Sri Lanka the national Anti‐Filaria Campaign (AFC) has routinely employed fenthion since 1974 for larvicidal control of Culex quinquefasciatus, the vector of Bancroftian filariasis in urban areas, where this mosquito breeds prolifically in polluted waters. During 1994 the efficacy of AFC fenthion treatment against organophosphate‐resistant Cx quinquefasciatus was investigated at Dehiwela, near Colombo.The AFC target rate of fenthion application was 1 mg a.i./l, but the actual concentrations of fenthion in freshly treated pits ranged from 0.64 to 63.2 mg a.i./l. There was significant suppression of larval densities in treated soakage pits, the predominant breeding site of Cx quinquefasciatus, although the mosquito population was 6‐fold resistant to fenthion at the LCW level. Production of pupae was almost completely prevented in soakage pits which were sprayed weekly with fenthion, indicating that adult mosquito emergence from this source was minimal. The rapid decline in concentration of fenthion detected in the water of soakage pits indicated that a weekly treatment schedule is essential for effective control. With the rapid recolonization of treated sites, the weekly schedule must be strictly implemented in order to achieve control of resistant larvae. Fenthion activity levels detected in treated pits suggest that a 7–10 day schedule of retreatment would completely suppress susceptible Cx quinquefasciatus.
Mosquito seasonality and arboviral disease incidence in Murray Valley, southeast Australia
Authors: DHILEEPAN K. 
Published: March 2008

Abstract. Adult female mosquito populations were monitored at weekly intervals during spring‐autumn (November‐March) for 4 years (1991‐95) using dry‐ice‐baited light traps at forty sites in the Murray Valley of Victoria, Australia. Among twenty species of mosquitoes collected, Culex annulirostriswas the most abundant (66.6 ± 9.3%) followed by Cx australicus(15.3 ± 7.7%). From a total of 476, 682 mosquitoes collected, nearly all were females and only 1295 (0.27%) were males.Mosquito population densities were generally higher in 1992‐93 and 1993‐94 seasons than in 1991‐92 and 1994‐95 seasons. Greatest densities of Cx annulirostrisand Cx australicusoccurred in 1992‐93, coinciding with outbreaks of Ross River (RR) and Barman Forest (BF) arboviruses causing human polyarthritis. In the majority of shires, Cx australicuswas the predominant species from spring to early summer (November and December), then was replaced by Cx annulirostrisfrom mid‐summer to autumn (January‐April). In three shires, Aedes bancroftianusand Ae.sagaxpredominated during the early part of the season. Densities of both Cx annulirostrisand Cx australicuswere related to temperature. Cx australicusadults were found to be trapped when the mean ambient temperature exceeded 6d̀C, with peak population recorded at 20d̀C. Cx annulirostrisadult density increased when the mean temperature rose above 12d̀C, reaching a peak during February and March when temperature exceeded 25d̀C. Cx annulirostrisdeclined rapidly from April onwards, with no adult activity evident from May to November.Population densities of Aedesspp. were generally less than reported from earlier studies, possibly due to lower rainfall in spring and summer as well as reduced flood irrigation practices. In each year, a significant correlation was detected between Cx annulirostrisdensity and RR virus incidence in humans. As Cx annulirostrisis the predominant local mosquito species and feeds on a wide spectrum of hosts including man, it seems likely that Cx annulirostrisis the major vector of RR in the inland Murray Valley region.
Comparison of three methods for age‐grading of female Neotropical phlebotomine sandflies
Authors: AÑEZ NESTOR , TANG YINSHAN 
Published: March 2008

Abstract. Changes in appearance of the accessory glands (AG), ovaries (OV) and the absence or presence of crease marks at the edges of the genital atrium armature (GA) were compared as methods to age‐grade female laboratory‐bred (Lutzomyia migonei) and wild‐caught (Lu.youngi, Lu.spinicrassa, Lu.ovallesi) Neotropical sandflies.Dissections at different physiological stages revealed that all parous and high proportions of nulliparous (4/38 unmated, 12/12 mated) females showed similar residual AG secretions. Hence AG appearance (nullipars with AG translucent, versus yellowish opaque granulated AG previously regarded as signs of parousness) is unreliable for age‐grading.Readily recognizable changes in both GA (98% creased) and the OV (100% yellowish with loose ovarioles) indicated that these organs could be employed to discriminate between nulliparous and parous females. Despite finding one misdiagnosed female (a nullipar having creased GA indicative of parity), the GA method of age‐grading is recommended because females may be examined satisfactorily at any stage of the gonotrophic cycle. Moreover, the GA characteristics of pickled or dry preserved sandflies as well as fresh slide‐mounted specimens can be determined easily.Among sixty‐five wild‐caught Lutzomyia females dissected (mostly Lu.spinicrassa and Lu.youngi), the proportions of specimens yielding preparations suitable for examination were 97% for GA, 89% for OV, but only 58% for AG, which reinforces GA as the preferred character for age‐grading.
Anopheles gambiae gonotrophic cycle duration, biting and exiting behaviour unaffected by permethrin‐impregnated bednets in The Gambia
Authors: QUIÑONES M. L. , LINES J. D. , THOMSON M. C. , JAWARA M. , MORRIS J. , GREENWOOD B. M. 
Published: March 2008

Abstract. Permethrin‐impregnated bednets protect children against malaria in The Gambia, where Anopheles gambiae complex mosquitoes are the main vectors of malaria. However, no effect has been found on mosquito density, parous rates or sporozoite rates in An.gambiae sensu lato populations; only a reduction in the numbers of mosquitoes resting indoors in rooms with treated bednets. A possible explanation for this paradox is that exposure to treated bednets leads to changed vector behaviour such as a shift in biting time, a diversion to biting outdoors instead of indoors, to biting animals instead of humans, or to increased duration of the gonotrophic cycle. To investigate these possibilities, we observed the biting and exiting behaviour of An.gambiae in ten pairs of villages, in half of which the residents used permethrin‐treated bednets. The possible influence of treated bednets on the gonotrophic cycle length was evaluated by mark‐release‐recapture experiment.No significant difference was found between villages with treated and untreated bednets in the indoor/outdoor ratio of human biting, in mean biting times or in human blood indices of An.gambiae females found resting indoors in the mornings. The proportions of unfed, fed or gravid An.gambiae females collected in exit traps, and the number of females exiting showed no significant differences between rooms with treated and untreated bednets. Indications for a gonotrophic cycle length of 2 days were found. No evidence for any change in duration of the gonotrophic cycle in relation to exposure to treated bednets was found, although the number of recaptures was low in the villages with treated bednets.Since equal numbers of infective An.gambiae were found in villages with treated or untreated bednets, and no changes in mosquito behaviour were detected, we cannot account for how children are protected against malaria by treated bednets. One possibility is that mosquitoes divert to bite other hosts, including adults.
Observations on the mite fauna associated with adult Stomoxys calcitmns in the U.K.
Authors: McGARRY J. W. , BAKER A. S. 
Published: March 2008

Abstract. Adult females of the blood‐sucking muscid Stomoxys calcitrans sampled between June and September 1993 from a cattle farm (n= 839) and from a pig farm (n= 542) in North‐West England were examined for mites. Twelve species of mites from ten families and three orders were identified as follows. In the Prostigmata, Eryenetes sp., Family Ereynetidae and Pediculaster mesembrinae, Family Pygmephoridae. In the Astigmata, Procalvolia zacheri Family Saproglyphidae, Acarusfarris, Family Acaridae, Bonomoia sphaerocerae and Myianoetus sp., Family Anoetidae. In the Mesostigmata, Macrocheles muscaedomesticae and Macrocheles subbadius Family Macrochelidae, Digamasellus sp., Family Digamasellidae, Halolaelaps sp., Family Halolaelapidae. Prodinychus sp., Family Uropodoidea and Thinoseius sp., Family Eviphididae. Mean infestation rates at the two sites (all mite species) for the entire sampling period were 31.6 ± 13.9% and 19.8 ± 3.6% respectively. 51 % of synbovine flies sampled in July were infested with mites. Mean numbers of flies infested in August at both farms were significantly lower compared to other months. The presence of tritonymphs of Ereynetes sp. on S.calcitrans demonstrates for the first time that this life cycle stage is naturally associated with insects in the field.All mites were recovered from the ventral thorax and abdomen, and two or more species commonly infested individual flies. Associations of mites with their dipteran hosts are described and discussed.
Comparison of the susceptibility of different Glossina species to simple and mixed infections with Trypanosoma (Nannomonas) congolense savannah and riverine forest types
Authors: REIFENBERG J. M. , CUISANCE D. , FREZIL J. L. , CUNY G. , DUVALLET G. 
Published: March 2008

Abstract Teneral Glossina morsitans mositans, G.m.submorsitans, G.palpalis gambiensis and G.tachinoides were allowed to feed on rabbits infected with Trypanosoma congolense savannah type or on mice infected with T.congolense riverine‐forest type. The four tsetse species and subspecies were also infected simultaneously in vitro on the blood of mice infected with the two clones of T.congolense via a silicone membrane. The infected tsetse were maintained on rabbits and from the day 25 after the infective feed, the surviving tsetse were dissected in order to determine the infection rates.Results showed higher mature infection rates in morsitans‐gwup tsetse flies than in palpalis‐group tsetse flies when infected with the savannah type of T.congolense. In contrast, infection rates with the riverine‐forest type of T.congolense were lower, and fewer flies showed full development cycle. The intrinsec vectorial capacity of G.m.submorsitans for the two T.congolense types was the highest, whereas the intrinsic vectorial capacity of G.p.gambiensis for the Savannah type and G.m.morsitans for the riverine‐forest type were the lowest. Among all tsetse which were infected simultaneously with the two types of T.congolense, the polymerase chain reaction detected only five flies which had both trypanosome taxa in the midgut and the proboscis. All the other infections were attributable to the savannah type.The differences in the gut of different Glossina species and subspecies allowing these two sub‐groups of T.congolense to survive better and undergo the complete developmental cycle more readily in some species than other are discussed.
Bacillus subtilis GlnR contains an autoinhibitory C‐terminal domain required for the interaction with glutamine synthetase
Authors: Wray Lewis V. , Fisher Susan H. 
Published: March 2008

SummaryThe Bacillus subtilis GlnR transcription factor regulates gene expression in response to changes in nitrogen availability. Glutamine synthetase transmits the nitrogen regulatory signal to GlnR. The DNA‐binding activity of GlnR is activated by a transient protein–protein interaction with feedback‐inhibited glutamine synthetase that stabilizes GlnR–DNA complexes. This signal transduction mechanism was analysed by creating mutant GlnR proteins with partial or complete truncations of their C‐terminal domains. The truncated GlnR proteins were found to constitutively repress gene expression in vivo. This constitutive repression did not require glutamine synthetase. Purified mutant GlnR proteins bound DNA in vitro more tightly than wild‐type GlnR protein and this binding was not activated by feedback‐inhibited glutamine synthetase. While full‐length GlnR is monomeric, the truncated GlnR proteins contained significant levels of dimers. These results indicate that the C‐terminal region of GlnR acts as an autoinhibitory domain that prevents GlnR dimerization and thus impedes DNA binding. The GlnR C‐terminal domain is also required for the interaction between GlnR and feedback‐inhibited glutamine synthetase. Compared with the full‐length GlnR protein, the truncated GlnR proteins were defective in their interaction with feedback‐inhibited glutamine synthetase in cross‐linking experiments.
CLINICAL STUDY: Cocaine craving is associated with electrophysiological brain responses to cocaine‐related stimuli
Authors: Franken Ingmar H. A. , Dietvorst Roeland C. , Hesselmans Mirjam , Franzek Ernst J. , Van De Wetering Ben J. M. , Van Strien Jan W. 
Published: March 2008

ABSTRACTSeveral studies show that substance dependence disorders are characterized by an enhanced processing of substance‐related stimuli. The present study was designed to examine the association between craving levels and selective processing of drug cues in cocaine‐dependent patients using event‐related brain potentials (ERPs). In abstinent cocaine‐dependent patients and a healthy control group, we studied the late positive potential (LPP) amplitudes elicited by neutral and cocaine‐related stimuli. The results show that cocaine‐dependent patients have an enhanced electrophysiological response in the late LPP time window to cocaine‐related stimuli as compared to controls, suggesting an enhanced processing of these stimuli. Most importantly, a robust association was observed between cocaine craving and LPP amplitude. High craving levels were associated with larger LPP amplitudes at central electrode sites in the right hemisphere. These findings are in line with theories linking motivational aspects and appetitive stimulus processing. Furthermore, it is demonstrated that ERPs are a useful index to assess motivational properties of stimuli in cocaine‐dependent patients. These findings suggest that electrophysiological measures may have clinical relevance in substance use disorders.
Chilling Tolerance in Hybrid Maize Induced by Seed Priming with Salicylic Acid
Authors: Farooq M. , Aziz T. , Basra S. M. A. , Cheema M. A. , Rehman H. 
Published: March 2008

AbstractThe optimum temperature for maize germination is between 25 and 28 °C. Poor and erratic germination at suboptimal temperature is the most important hindrance in its early sowing. This study was conducted to induce chilling tolerance in hybrid maize (Zea mays L.) by seed priming with salicylic acid (SA) and to unravel the background biochemical basis. For seed priming, maize hybrid (Hycorn 8288) seeds were soaked in 50, 100 and 150 ppm (mg l−1) aerated solutions of SA for 24 h and were dried back. Treated and untreated seeds were sown at 27 °C (optimal temperature) and at 15 °C (chilling stress) under controlled conditions. Performance of maize seedlings was hampered under chilling stress. But seed priming with SA improved the seedling emergence, root and shoot length, seedling fresh and dry weights, and leaf and root score considerably compared with control both at optimal and chilling temperatures. However, priming in 50 mg l−1 SA solution was more effective, followed by priming in 100 mg l−1 SA solution. Seed priming with SA improved the chilling tolerance in hybrid maize mainly by the activation of antioxidants (including catalase, superoxide dismutase and ascorbate peroxidase). Moreover, maintenance of high tissue water contents and reduced membrane permeability also contributed towards chilling tolerance.
In vitro effect of cyclosporine‐A on angiotensins secretion by glomerular cells
Authors: BERGAMASCO LUCA , SAINAGHI PIER PAOLO , CASTELLO LUIGI , LETIZIA CLAUDIO , BARTOLI ETTORE 
Published: March 2008

SUMMARY:Aim:  Cyclosporine‐A (CyA) is used to control transplant rejections and to treat autoimmune diseases. We investigated the possibility that changes induced by CyA on endothelin 1 (ET), angiotensin I (AI) and angiotensin II (AII) concentrations recognize a common pathway through which different mechanisms operate.Methods:  We measured ET, AI and AII concentrations, before and after either ET or CyA addition to the incubation medium of glomeruli of pig kidneys, isolated in vitro. The measurements were carried out with or without selective (ETA and ETB) or unselective ETA‐ETB receptor inhibitors.Results:  In the presence of CyA, AI and ET are positively correlated either when ETB receptors are blocked, or when both receptors are free, while this correlation becomes negative when ETA receptors alone are blocked. Adding ET to the medium, the correlations between AI and ET are negative when either ETA, or ETB or both are blocked. The effects of CyA and ET are significant only during the first 2 h of incubation.Conclusion:  Cyclosporine‐A recruits angiotensins and ET through ETA receptors, a mechanism possibly responsible of glomerular damage. This stimulation is time‐dependent. Prevention of the renal damage from CyA should require selective ETA receptor blockade.