bluuebunny/crossref_metadata_2025 huggingface dataset:
The nutritional state of male tsetse flies, Glossina pallidipes, at the time of feeding
Authors: BAYLIS MATTHEW , NAMBIRO CHARLES O.
Published: March 2008

Abstract. The feeding intervals of tsetse flies have been estimated from the nutritional state of flies caught in traps. However, such estimates have been disputed on the grounds that traps catch a biased, hungry sample of the flies which are seeking hosts and will feed. In this paper we present data on the nutritional state of tsetse flies caught approaching and feeding on oxen. Individual oxen were surrounded with an incomplete ring of electric nets which caught Glossina pallidipes Austen that were approaching, departing unfed and departing fed from an ox. Non‐teneral males caught in this way were analysed for their fat and haematin contents. The feeding interval was estimated from a comparison of the frequency distributions of the pre‐ and post‐feed haematin contents of the flies which fed. The former was not measured directly, and was deduced from the frequency distributions of the haematin contents of the male flies caught approaching and departing unfed from the oxen, since it is assumed that the departing unfed and fed flies together form a sample of the approaching flies. There was no difference between the frequency distributions of haematin contents of flies caught approaching and departing unfed, and therefore the pre‐feed haematin contents of the males which fed should have the same frequency distribution. Comparison of this distribution with that of the post‐feed haematin contents of the males which fed indicated that the majority of male G.pallidipes were returning to feed after digesting on average 1.4 log haematin units of the previous bloodmeal. From data published elsewhere, this corresponds to a mean feeding interval of 42‐60h. There was a strong, linear, negative relationship between the fat contents of males and their probability of taking a bloodmeal, suggesting that fat content is important in determining the feeding behaviour of tsetse flies.
Impact of permethrin‐impregnated mosquito nets compared with DDT house‐spraying against malaria transmission by Anopheles farauti and An.punctulatus in the Solomon Islands
Authors: HII JEFFREY L. K. , KANAI L. , FOLIGELA A. , KAN S. K. P. , BURKOT T. R. , WIRTZ R. A.
Published: March 2008

Abstract. In villages of northern Guadalcanal in the Solomon Islands, where the predominant malaria vector is An.farauti No. 1 and An. puctulatus is also involved, malaria transmission rates were compared for three zones: (1) non‐intervention: 438 people in seventeen villages; (2) residual DDT house‐spraying two cycles per year: 644 people in thirty villages; (3) bednets impregnated with permethrin 0.5 g/m2 twice per year, used by 580 people in sixteen villages. Regular DDT spraying in zones 1 and 3 had been withdrawn 18 months previously.

Malariological blood smear surveys of children aged 1‐9 years in August 1986 to January 1987 showed a mean‐baseline malaria parasite rate of 38% (32/84). By February 1988, 18 months after introduction of impregnated bednets, the Plasmodium falciparum infection rate in children was lowest in the zone using impregnated bednets (21% of 29), intermediate in the untreated zone (29% of 34) and highest in the DDT zone (46% of 53), but these differences were not statistically significant. P.vivax infection rates were 9–14%.

Using ELISA tests for malaria circumsporozoite antigen in the vectors, overall positivity rates were 0.7% of 49,902 An.farauti and 2.54% of 118 An.punctulatus, comprising 228 P.falciparum and 124 P. vivax infections. In the study zones, vector positivity rates were 0.93% of 31,615 An.farauti in the untreated zone; 0.32% of 16, 883 An.farauti in the DDT zone; 0.07% of 1404 An.farauti and 2.54% of 118 An.puctulatus in the impregnated bednet zone. There was no significant correlation between malaria parasite rates in the vectors and the children.

Entomological inoculation rates were consistently highest in the untreated zone (1.6–2.8 infective bites/night), intermediate in the DDT zone (0.8– 1.1/night) and significantly lowest in the bednet zone (0.03‐0.23/night). Geometric mean densities of P.falciparum sporozoites were also significantly higher in the DDT zone (50% > 10,000 sporozoites/mosquito compared with 20% in untreated zone). The highest individual infection density was an estimated 52,080 sporozoites of P.falciparum in a specimen of An.punctulatus from the bednet zone. P.vivax sporozoite densities were not significantly different between zones, and both species of vector had similar mean sporozoite loads for both species of malaria.

It is concluded that permethrin‐impregnated mosquito nets exerted significantly more impact on vector infectivity and the inoculation rate than resulted from DDT spraying. Even so, the inoculation rate for people in the bednet zone remained at one infective bite every 4–32 days, an insufficient reduction to control malaria without additional countermeasures. Ineffectiveness of house‐spraying and the limited impact of impregnated bednets are attributed to exophily and other behavioural aspects of An. farauti.
Reduced susceptibility of Anopheles gambiae to permethrin associated with the use of permethrin‐impregnated bednets and curtains in Kenya
Authors: VULULE J. M. , BEACH R. F. , ATIELI F. K. , ROBERTS J. M. , MOUNT D. L. , MWANGI R. W.
Published: March 2008

Abstract. Susceptibility of the malaria vector Anopheles gambiae to permethrin decreased following the installation of mosquito nets impregnated with 0.5 g permethrin per square metre in four villages near Kisumu, Kenya. During the first year that permethrin‐impregnated bednets and curtains were in place, the exposure time to 50% mortality (LT50) increased 2.5‐fold from 13 to 33min, while the LT5() for An.gambiae was unchanged in two other villages where no intervention measures were used. Two years after permethrin‐impregnated mosquito nets were distributed the LT50s for An.gambiae were 28, 28 and 16min, respectively, in the villages with bednets, curtains and with no such intervention.

Using a colony of An.gambiae derived from females collected in the villages using permethrin‐impregnated moquito nets, we lengthened the LT5n from 28 to 41 min in two generations by exposing all females to permethrin‐treated papers for 60 min and rearing offspring of the survivors.

Permethrin‐impregnated bednets and curtains are intended to reduce vectorial capacity. Reduced susceptibility to permethrin could counter this beneficial effect.
Pyrethroid‐sprayed tents for malaria control
Authors: HEWITT SEAN , ROWLAND MARK , MUHAMMAD NASIR , KAMAL MUHAMMAD , KEMP ELIZABETH
Published: March 2008

Abstract>

Field trials were undertaken in the North West Frontier Province of Pakistan to determine the effects of pyrethroid‐sprayed tents on feeding success, mortality and biting‐rates of wild mosquitoes attracted to bait cows confined within the tents. Under natural conditions, endophagic mosquitoes rested only briefly in untreated tents during the night, followed by complete exodus at dawn.

In tents sprayed on the interior surface with permethrin 0.5 mg/m2 or with deltamethrin 0.03 g/m2 the biting rate of Anopheles stephensi was reduced by about 40%; detergency against culicines and other anophelines was much less. Mortality‐rates of bloodfed mosquitoes from the treated tents were 75%An.stephensi, 65%An. subpictus but only 10% of culicines.

Outer fly‐sheets prolonged the effective life of the treatment; bioassays on the sprayed inner‐sheets showed that insecticidal efficacy remained high for over a year, whereas on tents without fly‐sheets permethrin residual efficacy declined rapidly 20–40 weeks post‐treatment. It is concluded that tent‐spraying with fast‐acting photostable residual pyrethroid insecticide would probably provide effective protection against malaria transmission for the inhabitants of tents in any part of the world where the vector mosquitoes are endophilic and susceptible to pyrethroids.
A simple, sterile food source for rearing the larvae of Lucilia sericata (Diptera: Calliphoridae)
Authors: SHERMAN RONALD A. , TRAN JULIE MY‐TIEN
Published: March 2008

arvae of the sheep blowfly Lucilia sericata (Meigen) were reared on various mixtures of puréed liver, agar, brewer's yeast and trypsin, in order to develop a simple, sterile, tissue‐based diet. Growth and survival rates of larvae reared on a sterile 1:1 mixture of puréed liver with 3% Bacto agar equalled or exceeded those of larvae reared on raw liver. The addition of yeast and/or trypsin to the medium was of no additional benefit. This sterile, homogenous, tissue‐based substrate offers a simple, convenient, inexpensive growth medium for rearing larvae for maggot therapy, and for testing the effects of various chemicals and dietary constituents on necrophagous insect larvae. It may be useful, therefore, in studies of myiasis, forensic entomology, and toxicology. This rearing medium also has the advantage that it can be stored for many months at room temperature without progressive decomposition or offensive odour.
Permethrin resistance in the head louse Pediculus capitis from Israel
Authors: MUMCUOGLU KOSTA Y. , HEMINGWAY JANET , MILLER JACQUELINE , IOFFE‐USPENSKY INNA , KLAUS SIDNEY , BEN‐ISHAI FIAMETA , GALUN RACHEL
Published: March 2008

Head lice, Pediculus capitis, were collected from children aged 3–12 years in Maale Adumin, a town near Jerusalem, after reports of control failure with the pyrethroid insecticide permethrin. A total of 1516 children were examined: living lice and eggs were found on 12.1% of the children; or another 22.8% of the children only nits were found. Twice as many girls as boys (8.1% v 4%) were infested with lice and or nits. Head lice collected from infested children were exposed to permethrin impregnated filter‐papers. Log time probit mortality (ltp) regression lines were calculated for mortality data and compared to ltp lines for a similar collection of head lice made in 1989. The regression lines for the two years were significantly different, with a 4‐fold decrease in susceptibility at the LT50 level between 1989 and 1994. The slopes of the lines also suggested that the 1994 population was more heterogenous in its response to permethrin than the 1989 population. In contrast, a laboratory population of body lice (Pediculus humanus) tested with the same batch of permethrin‐impregnated papers showed a slight but non‐significant increase in susceptibility between 1989 and 1994. The results suggest that resistance to pyrethroids has developed rapidly among head lice since permethrin was introduced in 1991 as a pediculicide in Israel.
Village trial of bednets impregnated with wash‐resistant permethrin compared with other pyrethroid formulations
Authors: MILLER J. E. , LINDSAY S. W. , ARMSTRONG J. R. M. , SCHELLENBERG  , ADIAMAH J. , JAWARA M. , CURTIS C. F.
Published: March 2008

Abstract. A village‐scale field trial of pyrethroid‐impregnated mosquito nets was undertaken in The Gambia, West Africa, in the Mandinka village of Saruja (13o13'N, 14o55'W) during July‐November 1989. Nearly all the villagers possessed and used their own bednets. Anopheles gambiae is the main vector of human malaria in the area.

An experimental wash‐resistant formulation of permethrin was compared with standard emulsifiable concentrate (EC) formulations of permethrin and lambda‐cyhalothrin, versus placebo‐treated bednets. Target concentrations of pyrethroids on bednets were permethrin 500mg/m2 and lambda‐cyhalothrin 25 mg/m2. The experimental design involved random allocation of a treatment to one net per family. Whereas 68% of people questioned said they washed their nets fortnightly, observations during the 16‐week trial period showed that only 4/130 (3%) of nets involved in the trial had been washed as frequently as once per month.

Early morning searches for mosquitoes under bednets (1 day/week for 16 weeks) found significantly more mosquitoes (60%An. gambiae) in placebo‐treated nets than in pyrethroid‐treated nets. The numbers found with each of the three pyrethroid treatments did not differ significantly from each other. Insecticidal efficacy of the treatments was tested by bioassays using wild‐caught unfed mosquitoes exposed to netting for 3min. Linear regression analysis of bioassay mortality against number of times that a net had been washed by villagers showed that nets impregnated with the wash‐resistant permethrin retained their insecticidal properties better than nets impregnated with lambda‐cyhalothrin or with the standard permethrin formulation.
Effects of temperature on virogenesis of bluetongue virus serotype 11 in Culicoides variipennis sonorensis
Authors: MULLENS BRADLEY A. , TABACHNICK WALTER J. , HOLBROOK FREDERICK R. , THOMPSON LEE H.
Published: March 2008

Abstract. Culicoides variipennis sonorensis females were fed bluetongue virus serotype 11 mixed in sheep blood and were held at constant temperatures of 32, 27, 21 and 15oC. Virogenesis, as measured by enzyme‐linked immunosorbent assay (ELISA), proceeded significantly faster at higher temperatures. Based on ELISA absorbance ≥0.2, some flies first were categorized as infected after 1 day, 2 days and 4 days at 32, 27 and 21oC, respectively. Peak levels of virus antigen were seen after 5–7, 7–13 and 18–22 days for flies held at 32, 27 and 21oC, respectively. There was no significant virus replication in flies held at 15oC for 22 days, but latent virus replicated and was detected easily (44% infection) 4–10 days after these flies were transferred to 27oC. The implications for temperature effects on bluetongue epizootiology are discussed.
Relationships between host blood factors and proteases in Glossina morsitans subspecies infected with Trypanosoma congolense
Authors: MIHOK STEVE , MACHIKA CHRISTOPHER , DARJI NAFISA , KANG'ETHE RASTUS K. , OTIENO LEONARD H.
Published: March 2008

Abstract. Host blood effects on Trypanosoma congolense establishment in Glossina morsitans morsitans and Glossina morsitans centralis were investigated using goat, rabbit, cow and rhinoceros blood. Meals containing goat erythrocytes facilitated infection in G. m. morsitans, whereas meals containing goat plasma facilitated infection in G. m. centralis. Goat blood effects were not observed in the presence of complementary rabbit blood components. N‐acetyl‐glucosamine (a midguMectin inhibitor) increased infection rates in some, but not all, blood manipulations. Cholesterol increased infection rates in G. m. centralis only. Both compounds together added to cow blood produced superinfection in G. m. centralis, but not in G. m. morsitans. Midgut protease levels did not differ 6 days post‐infection in flies maintaining infections versus flies clearing infections. Protease levels were weakly correlated with patterns of infection, but only in G. m. morsitans. These results suggest that physiological mechanisms responsible for variation in infection rates are only superficially similar in these closely‐related tsetse.
Malaria‐induced reduction of fecundity during the first gonotrophic cycle of Anopheles Stephensi mosquitoes
Authors: HOGG JON C. , HURD HILARY
Published: March 2008

Abstract. Anopheles stephensi mosquitoes which had fed upon mice infected with Plasmodium yoelii nigeriensis malaria parasites produced significantly fewer eggs than mosquitoes fed on an uninfected mouse. Fecundity reduction was more pronounced when the bloodmeal contained malaria gametocytes and the mosquitoes developed oocysts. Egg production and haematin excretion were correlated for uninfected bloodfed mosquitoes; the presence of P.y. nigeriensis in the blood affected this relationship. Reduced fecundity was associated with a significant reduction of bloodmeal size (measured by haematin excretion) in mosquitoes which ingested gametocytaemic blood. The bloodmeal size in mosquitoes fed on parasitaemic blood without gametocytes was not significantly reduced. The use of haematin assays for determination of bloodmeal size in mosquitoes is discussed.
Anopheles culicifacies in Baluchistan, Iran
Authors: ZAIM M. , MANOUCHEHRI A. V. , MOTABAR M. , EMADI A. M. , NAZARI M. , PAKDAD K. , KAYEDI M. H. , MOWLAII G.
Published: March 2008

Abstract. Anopheles culicifacies (probably species A) is the main vector of malaria in Baluchistan, southeastern Iran. Adult mosquitoes were collected during 1990‐92 by five methods of sampling: knock‐down pyrethrum space‐spray indoors, human and animal bait (18.00–05.00 hours), pit shelters and CDC light traps, yielding 62%, 3%, 6%, 4% and 25% of specimens, respectively. Whereas spray‐catches comprised c. 70% gravid and semi‐gravid females, light trap catches were mostly (c. 60%) unfed females, while females from pit shelters comprised all abdominal stages more equally (13–36%). An. culicifacies populations peaked in April‐May and rose again during August‐November. Densities of indoor‐resting mosquitoes were consistently greater in an unsprayed village than in villages subjected to residual house‐spraying with propoxur, malathion or pirimiphos‐methyl. Monthly malaria incidence generally followed fluctuations of An. culicifacies density, usually with a peak in May‐June.
Low‐volume application by mist‐blower compared with conventional compression sprayer treatment of houses with residual pyrethroid to control the malaria vector Anopheles albimanus in Mexico
Authors: VILLARREAL C. , RODRIGUEZ M. H. , BOWN D. N. , ARREDONDO‐JIMÉNEZ J. I.
Published: March 2008

Abstract. Village‐scale trials were carried out in southern Mexico to compare the efficacy of indoor‐spraying of the pyrethroid insecticide lambda‐cyhalothrin applied either as low‐volume (LV) aqueous emulsion or as wettable‐powder (WP) aqueous suspension for residual control of the principal coastal malaria vector Anopheles albimanus. Three indoor spray rounds were conducted at 3‐month intervals using back‐pack mist‐blowers to apply lambda‐cyhalothrin 12.5 mg a.i./m2 by LV, whereas the WP was applied by conventional compression sprayer at a mean rate of 26.5 mg a.i./m2.

Both treatments caused mosquito mortality indoors and outdoors (collected inside house curtains) as a result of contact with treated surfaces before and after feeding, but had no significant impact on overall population density of An. albimanus resting indoors or assessed by human bait collections. Contact bioassays showed that WP and LV treatments with lambda‐cyhalothrin were effective for 12–20 weeks (>75% mortality) without causing excito‐repellency.

Compared to the WP treatment (8 houses/man/day), LV treatment (25 houses/man/day) was more than 3 times quicker per house, potentially saving 68% of labour costs. This is offset, however, by the much lower unit price of a compression sprayer (e.g. Hudson ‘X‐pert’ at US120) than a mist‐blower (e.g. ‘Super Jolly’ at US350), and higher running costs for LV applications. It was calculated, therefore, that LV becomes more economical than WP after 18.8 treatments/100 houses/10 men at equivalent rates of application, or after 7.6 spray rounds with half‐rate LV applications.
Characterization of body louse midgut proteins recognized by resistant hosts
Authors: OCHANDA JAMES O. , MUMCUOGLU KOSTA Y. , BEN‐YAKIR DAVID , OKURU J. K. , ODUOL V. O. , GALUN RACHEL
Published: March 2008

Abstract. The human body louse, Pediculus humanus, showed eighteen midgut proteins ranging between 12 and 117 kDa, when analysed by SDS‐PAGE electrophoresis. Seven of them (12 kDa, 17 kDa, 29 kDa, 35 kDa, 40 kDa, 55 kDa and 97 kDa) were major bands based on their intensity of staining. The immunization of rabbits with a midgut extract elicited the production of protective polyclonal antibodies. These antibodies reacted strongly with all major midgut proteins as well as with 63 kDa and 117 kDa proteins when tested by the Western blot technique. The analysis of the proteins revealed that the 12 kDa, 25 kDa, 29 kDa, 35 kDa, 45 kDa, 87 kDa and 97 kDa proteins are glycosylated and none of them contained a lipid moiety. By electroelution, the proteins of 35 kDa and 63 kDa were purified. On trypsinization, the proteins of 35 kDa and 63 kDa produced four major fragments (F, F2, F3, and F4) when resolved on a 18% SDS‐PAGE. The Fj fragment of the 35 kDa protein reacted with me polyclonal antibodies by the immunoblot technique.
The effect of host blood in the in vitrotransformation of bloodstream trypanosomes by tsetse midgut homogenates
Authors: NGUU EDWARD K. , OSIR ELLIE O. , IMBUGA MABEL O. , OLEMBO NORAH K.
Published: March 2008

Abstract. Midgut homogenates prepared from Glossina morsitans morsitans, that had previously been fed on different host blood samples, were tested for their abilities to transform bloodstream Trypanosoma bruceiinto procyclic (midgut) forms in vitro.Compared to rat and goat blood samples, eland blood had the least capacity to support trypanosome transformation, whereas buffalo blood showed intermediate capacity. Fractionation of rat blood showed the importance of the cellular portion since both rat and eland red blood cells (RBCs) supported the process. Virtually no transformation was observed in rat and eland plasma or serum fractions. Suspending rat blood cells in eland plasma led to a reduction in parasite transformation rates. Further experiments showed that the RBC membranes were also capable of supporting the process. These results clearly show the important role played by blood, especially the red blood cells, in the transformation of bloodstream trypanosomes. In addition, the low transformation rates observed in eland blood is due to an inhibitory factor(s) present in the plasma fraction.
Distribution, prevalence and host associations of Hymenoptera parasitic on Calliphoridae occurring in flystrike in New Zealand
Authors: BISHOP D. M. , HEATH A. C. G. , HAACK N. A.
Published: March 2008

Abstract. Between 1920 and 1930, four species of parasitoid Hymenoptera (Tachinaephagus zealandicus, Alysia manducator, Nasonia vitripennisand Brachymeria ucalegon)were imported to New Zealand as an aid in the control of the blowflies causing myiasis in sheep (flystrike). Their long‐term effects have never been investigated and the extent to which they were successful in establishing and enlarging their ranges has been given scant regard over the last 60 years. A long‐term epidemiological study of flystrike in New Zealand between 1986 and 1996 obtained 4061 samples of blowfly larvae from flystruck sheep and carrion and overall 1.1% of these larval samples (most from the North Island) were found to be parasitized. Tachinaephagus zealandicusand A. manducatorwere present in field strikes, together with the endemic Aphaereta aotearecently found to be a parasite of calliphorids. The endemic species Phaenocarpa antipodawas found in association with carrion but not flystrike. Neither N.vitripennisnor B.ucalegonwere isolated from larvae in field strikes, the former because it parasitizes only pupae and the latter may be extinct as it has not been sighted since its introduction in 1919.

It is concluded that if parasitoid wasps are able to locate and parasitize blowfly larvae on struck sheep, then their parasitism rate on more accessible larvae on carcases may be correspondingly greater. For this reason their scope for use in integrated management of flystrike could be increased by culturing and field release.
Spectral sensitivity in the eyes of male and female Lutzomyia longipalpissandflies
Authors: MELLOR HELEN E. , HAMILTON JAMES G. C. , ANDERSON MORAY
Published: March 2008

Abstract. Using electroretinogram recordings, the response of Lutzomyia longipalpissandfly eyes to a range of wavelengths of light was measured, and spectral sensitivity determined. The eyes of both male and female adult sandflies were found to respond maximally to light in the ultraviolet region (at 340 nm) with a secondary peak in the blue‐green‐yellow region at 520 nm for females and 546 nm for males. The Mann‐Whitney U test showed no significant differences between males and females at corresponding wavelengths.
Behaviour of Anopheles albimanus in relation to pyrethroid‐treated bednets
Authors: ARREDONDO‐JIMÉNEZ JUAN I. , RODRIGUEZ MARIO H. , LOYOLA ENRIQUE G. , BOWN DAVID N.
Published: March 2008

Abstract. Responses of the malaria vector Anopheles albimanus to pyrethroid impregnated bednets made of cotton or nylon, compared with untreated nets, were investigated in houses occupied by two people inside and/or outside two bednets, in coastal Chiapas, México. The pyrethroid used was lambdacyhalothrin 30mga.i./m2. Bioassay mortality rates of An.albimanus exposed to treated nets for 3 or 15min, rose from 40–55% to 90–100% for nylon nets 3–19 weeks post‐treatment, but were consistently lower for treated cotton nets.

An.albimanus females (collected unfed on human bait) were released in houses surrounded by curtains for trapping mosquitoes that exited from the house. Floor sheets were used in and around each experimental house for retrieving any mosquitoes knocked‐down and/or killed. During post‐treatment assessment for 17 weeks, An.albimanus blood‐feeding success rates were 23–24% with untreated nets, 14–18% with treated cotton nets and 8–15% with treated nylon nets, significantly reduced when both human baits were inside the treated bednets, but not when one or more baits were outside the treated bednet(s) within the house.

Proportions of mosquitoes leaving houses <3 h post‐release were 53–59% from houses with untreated bednets versus 65–78% with treated bednets. Except in one case (when both humans were outside treated cotton nets), these increased early exit rates were significant, whether or not the human baits were inside the treated bednets indoors. Mortality rates of An.albimanus females exiting overnight (22.00–06.00 hours) averaged 15–39% from houses with treated cotton and 16–46% with treated nylon nets, very significantly greater than the control mean rates of 6–8% mortality with untreated nets.

Observations on wild‐caught An. albimanus females marked with fluorescent powder and released indoors revealed that few mosquitoes (3–11 %) actually contacted the bednets unless both human baits remained under them ‐ when contact rates were 22% on treated nylon, 23% on treated cotton and 42% on untreated nets (P= 0.05). The mean resting time was significantly longer on untreated (14.4min) than on treated nylon (5.8min) or cotton (9.5 min) bednets, whereas mean resting times on other surfaces indoors were 16.5–19.8min. Proportions exiting within 2h of release were significantly more from houses with treated houses (33–35%) than with untreated nets (8%). However, mortality rates of mosquitoes that landed on treated nets were very significantly greater (90–100%) than after landing on untreated nets (10%). Thus, despite some excito‐repellency, lambdacyhalothrin‐impregnated bednets (especially made of nylon) proved to be effective as an alternative to house‐spraying against An.albimanus.
Gonotrophic and embryonic development of the Palaearctic screwworm fly Wohlfahrtia magnifies
Authors: RUIZ‐MARTINEZ I. , DIAZ‐LOPEZ M. , PEREZ‐JIMENEZ J. M.
Published: March 2008

Abstract. Gonotrophic and embryonic development of Wohlfahrtia magnifica were studied on pupae and adults reared in the laboratory. Gonotrophic development in screwworm begins 8 days after pupation in yellow eye pharate adults. The adult female emerges with its oocytes at stage 3 and requires only 2 days for complete oogenesis and 5 days for complete embryogenesis. Mating occurs 2–5 days after adult emergence, starting the embryonic development. Each female produces an average of 76.8 active larvae which can produce a traumatic lesion in their hosts. When food sources were regularly supplied, synchronization of gonotrophic stages can be observed. These stages together with the embryonic ones are described.
Use of rDNA‐PCR to investigate the ecological distribution of Anopheles bwambae in relation to other members of the An.gambiae complex of mosquitoes in Bwamba County, Uganda
Authors: HARBACH RALPH E. , TOWNSON HAROLD , MUKWAYA LOUIS G. , ADENIRAN TARA
Published: March 2008

Abstract Environmental relationships were investigated among three species of the Anopheles gambiae complex of mosquitoes associated with the geothermal springs located in Bwamba County, Uganda. The degree of ecological isolation between An.gambiae and An. bwambae, a sibling species known only from the geothermal springs environment, was assessed on the basis of adult distribution and abundance as well as differences in larval habitats. Field data were gathered during June 1995 without knowing which of the species were being collected. Specimens identified subsequently by rDNA‐PCR were used to interpret the ecological data. Ten of twenty aquatic sites sampled were found positive for immature stages of the An.gambiae complex.

Larvae of An.bwambae were associated with ‘springwater’ habitats having much higher conductivity, much greater concentrations of dissolved solids and slightly higher temperature and pH than ‘normal’ fresh water sites inhabited by larvae of An.gambiae. Larval habitats of both species were unshaded: An.bwambae occurred among dense sedge (Cyperus laevigatus) whereas those of An.gambiae were almost devoid of vegetation. One mixed sample showed that larvae of both species occur together in peripheral aquatic sites with intermediate physical and ecological characteristics.

In water preference tests, free‐flying females were reluctant to lay eggs on bowls of water in cages; gravid females (with one wing amputated) placed on the surface of water in a cup laid eggs on seasoned rainwater (12/51 An.bwambae; 2/3 An.gambiae) as well as spring‐water (39/51 An.bwambae; 1/3 An.gambiae). All three An.gambiae oviposited on the first water option, whereas 86% of An. bwambae witheld oviposition until being moved to the other type of water after 5–6 h, and 82% (36/44) of these laid eggs on geothermal water in preference to rainwater.

Larval and adult collections showed that An.gambiae occurs sympatrically with An.bwambae throughout its range in the humid foothill environment of the geothermal springs, whereas the distribution of An.arabiensis overlaps only slightly with An.bwambae towards the savanna environment north of the springs.
Genetics of hybridization of Glossina swynnertoni with Glossina morsitans morsitans and Glossina morsitans centralis
Authors: GOODING R. H.
Published: March 2008

Abstract Reciprocal crosses were performed with Glossina swynnertoni and Glossina morsitans morsitans and with G. swynnertoni and Glossina morsitans centralis, using strains that carried marker genes in all three linkage groups. Glossina swynnertoni males can inseminate, but not fertilize, G.m.morsitans; all other crosses produced some fertile females. Hybridization did not cause sex ratio distortion among F{ flies. Most F and backcross females were fertile, but all F, males were sterile. Sterility among backcross males was also high (99% in BXj, 85% in Bx2, and about 50% in Bx3 to Bx5). Chromosome transmission by hybrid females usually conformed to Mendelian expectations, but genetic recombination was lower than observed in G.m.morsitans. The reduction in fertility among backcross females was not associated with heterozygosity in any linkage group. Sterility among hybrid and backcross males was associated with heterozygosity of sex chromosomes and probably autosomes. The results support the systematic placement of G.swynnertoni closer to G.mxentralis than to G.m.morsitans.
Reproductive success by large, closely related males facilitated by sperm storage in an aggregate breeding amphibian
Authors: CHANDLER C. H. , ZAMUDIO K. R.
Published: March 2008

The outcome of sexual selection on males may depend on female mate choice and male–male competition as well as postcopulatory processes such as cryptic female choice and sperm competition. We studied the outcome of sexual selection in the spotted salamander (Ambystoma maculatum), specifically examining the role of body size and relatedness on male reproductive success. Using controlled mating experiments in the field, we gave females access to three males of different sizes. We used seven microsatellite loci to determine paternity in the resulting larvae, estimate relatedness (r) between females and their mates, and calculate md2 (a measure of within‐individual genomic divergence), heterozygosity, and standardized heterozygosity in the larvae. Both body size and relatedness to the female were significant predictors of male reproductive success. The relatedness of the males available to a female did not influence the amount of stored sperm she used to sire her larvae. Nonetheless, computer simulations showed that the average md2, heterozygosity, and standardized heterozygosity of the offspring were lower than expected by random mating. These differences are due to the use of stored sperm to fertilize some eggs; md2, heterozygosity, and standardized heterozygosity of larvae sired by stored sperm were significantly lower than those of larvae sired by the experimental males. These results suggest that relatedness may further influence a male's long‐term reproductive success by determining whether his sperm is stored for later breeding seasons. Sexual selection in this salamander likely involves a complex interaction among many factors and may act over many seasons.
The seabird paradox: dispersal, genetic structure and population dynamics in a highly mobile, but philopatric albatross species
Authors: MILOT EMMANUEL , WEIMERSKIRCH HENRI , BERNATCHEZ LOUIS
Published: March 2008

The philopatric behaviour of albatrosses has intrigued biologists due to the high mobility of these seabirds. It is unknown how albatrosses maintain a system of fragmented populations without frequent dispersal movements, in spite of the long‐term temporal heterogeneity in resource distribution at sea. We used both genetic (amplified fragment length polymorphism) and capture–mark–recapture (CMR) data to identify explicitly which among several models of population dynamics best applies to the wandering albatross (Diomedea exulans) and to test for migration–drift equilibrium. We previously documented an extremely low genetic diversity in this species. Here, we show that populations exhibit little genetic differentiation across the species’ range (ΘB < 0.05, where ΘBis anFSTanalogue). Furthermore, there was no evidence of hierarchical structure or isolation‐by‐distance. Wright'sFSTbetween pairs of colonies were low in general and the pattern was consistent with a nonequilibrium genetic model. In contrast, CMR data collected over the last decades indicated that about one bird per cohort has dispersed among islands. Overall,FSTvalues were not indicative of contemporary dispersal as inferred from CMR data. Moreover, all genotypes grouped together in a cluster analysis, indicating that current colonies may have derived from one ancestral source that had a low genetic diversity. A metapopulation dynamics model including a recent (postglacial) colonization of several islands seems consistent with both the very low levels of genetic diversity and structure within the wandering albatross. Yet, our data suggest that several other factors including ongoing gene flow, recurrent long‐distance dispersal and source‐sink dynamics have contributed to different extent in shaping the genetic signature observed in this species. Our results show that an absence of genetic structuring may in itself reveal little about the true population dynamics in seabirds, but can provide insights into important processes when a comparison with other information, such as demographic data, is possible.
A tale of two worlds: molecular ecology and population structure of the threatened Florida scrub‐jay
Authors: KOENIG WALTER D. , WALTERS ERIC L.
Published: March 2008

Elsewhere in this issue of Molecular Ecology, Coulon et al. provide a detailed analysis of population structure of the threatened Florida scrub‐jay (Aphelocoma coerulescens) using genetic markers and compare it to that inferred from previous demographic surveys and observed dispersal behaviour in this species. In contrast to previous attempts at such comparisons, estimates from the two methods are reasonably congruent. Although challenges remain, Coulon et al.'s analyses demonstrate the potential for closing the gap between these alternative methodologies, and ultimately for future genetic surveys to be used confidently in conservation planning.
What can transgenic parasites tell us about the development of Plasmodium‐specific immune responses?
Authors: THOMPSON J. , MILLINGTON O.R. , GARSIDE P. , BREWER J.M.
Published: March 2008

Malaria infects 500 million people and kills an estimated 2·7 million annually, representing one of the most significant diseases in the world. However, efforts to develop effective vaccines have met with limited success. One reason is our lack of basic knowledge of how and where the immune system responds to parasite antigens. This is important as the early events during induction of an immune response influence the acquisition of effector function and development of memory responses. Our knowledge of the interactions of Plasmodia with the host immune system has largely been derived through in vitro study. This is a significant issue as the component parts of the immune system do not work in isolation and their interactions occur in distinct and specialized micro‐ and macro‐anatomical locations that can only be assessed in the physiological context, in vivo. In this context, the availability of transgenic malaria parasites over the last 10 years has greatly enhanced our ability to understand and evaluate factors involved in host–parasite interactions in vivo. In this article, we review the current status of this area and speculate on what parasite transgenesis approaches will tell us about the development of Plasmodium‐specific immune responses in the future.
Advances in the use of genetically engineered parasites to study immunity to Toxoplasma gondii
Authors: DZIERSZINSKI F. S. , HUNTER C. A.
Published: March 2008

Studying in vivo biology and the host immune response to Toxoplasma gondii has yielded many insights into the pathogenesis of this parasitic organism. It is recognized that this infection in immune competent hosts elicits a strong Th1‐type response, which is characterized by the generation of parasite‐specific CD4+ and CD8+ T cells that produce IFN‐γ and provide protective immunity. One of the problems associated with studying resistance to Toxoplasma has been the lack of reagents to track parasite‐specific T cell responses with a high degree of specificity. To overcome this difficulty, it is possible to use a combination of transgenic parasites that are engineered to express well‐characterized heterologous reporters or antigens, and T cell hybridomas or naïve T cells that express a T cell receptor specific for the processed peptide. These approaches have provided new insights into parasite dissemination, antigen presDelivered as OEentation, as well as immune regulation.
The AAE14 gene encodes the Arabidopsis o‐succinylbenzoyl‐CoA ligase that is essential for phylloquinone synthesis and photosystem‐I function
Authors: Kim Hyun Uk , Oostende Chloë van , Basset Gilles J.C. , Browse John
Published: March 2008

Phylloquinone is the one‐electron carrier at the A1 site of photosystem I, and is essential for photosynthesis. Arabidopsis mutants deficient in early steps of phylloquinone synthesis do not become autotrophic and are seedling lethals, even when grown on sucrose‐supplemented media. Here, we identify acyl‐activating enzyme 14 (AAE14, At1g30520) as the o‐succinylbenzoyl‐coenzyme A (OSB‐CoA) ligase acting in phylloquinone synthesis. Three aae14 mutant alleles, identified by reverse genetics, were found to be seedling lethal, to contain no detectable phylloquinone (< 0.1 pmol mg−1 fresh weight) compared with 10 pmol mg−1 fresh weight in wild‐type leaves, and to accumulate OSB. AAE14 was able to restore menaquinone biosynthesis when expressed in an Escherichia coli mutant disrupted in the menE gene that encodes the bacterial OSB‐CoA ligase. Weak expression of an AAE14 transgene in mutant plants (controlled by the uninduced XVE promoter) resulted in chlorotic, slow‐growing plants that accumulated an average of 4.7 pmol mg−1 fresh weight of phylloquinone. Inducing the XVE promoter in these plants, or expressing an AAE14 transgene under the control of the CaMV 35S promoter, led to full complementation of the mutant phenotype. aae14‐mutant plants were also able to synthesize phylloquinone when provided with 1,4‐dihydroxy‐2‐naphthoate, an intermediate in phylloquinone synthesis downstream of the OSB‐CoA ligase reaction. Expression of an AAE14:GFP reporter construct indicated that the protein accumulated in discrete foci within the chloroplasts. This and other evidence suggests that the enzymes of phylloquinone synthesis from isochorismate may form a complex in the chloroplast stroma to facilitate the efficient channeling of intermediates through the pathway.
The response of bovine beta‐lactoglobulin‐specific T‐cell clones to single amino acid substitution of T‐cell core epitope
Authors: Kondo Masashi , Kaneko Hideo , Fukao Toshiyuki , Suzuki Kiyotaka , Sakaguchi Heima , Shinoda Shinji , Kato Zenichiro , Matsui Eiko , Teramoto Takahide , Nakano Taku , Kondo Naomi
Published: March 2008

Cow’s milk is one of the most common food allergens in the first year of life, with approximately 2.5% of infants experiencing an allergic reaction to it. Beta‐lactoglobulin (BLG) is one of the major allergens in cow’s milk. Previously, we reported that four of six T‐cell clones (TCC) which were established from cow’s milk allergy patients recognized BLGp97‐117 as the core sequence and also recognized BLG in association with the human leucocyte antigen (HLA)‐DRB1*0405 allele. Using two of these four TCCs, we evaluated the T‐cell response to BLG peptides with single amino acid substitution or deletion and identified BLGp102‐112 as the minimum essential region in BLGp97‐117. In the alanine‐scan assay, the proliferative responses of TCCs to pE108A disappeared, and the proliferative responses of TCCs to pC106A decreased. In the analog peptide proliferation assay, pY102S had retained some T‐cell response to the two TCCs. Collecting these results, we propose a motif for the interaction between the HLA‐DRB1*0405 allele and antigen peptide, and suggest that BLGp105‐108 are important residues to retain the TCR/BLG‐peptide/HLA complex. pY102A and pY102S are partial agonists for the T‐cell receptor. These peptides might be considered as candidate peptides for the modification of the T‐cell response to BLG in cow’s milk allergy.
Diagnostic Evaluation of Fat to Protein Ratio in Prolonged Calving to Conception Interval Using Receiver Operating Characteristic Analyses
Authors: Podpečan O , Mrkun J , Zrimšek P
Published: March 2008

Contents

Evaluation of fat to protein ratio (FPR) in milk was performed for the prediction of calving to conception interval (CC) in dairy cows. Reproduction parameters of 51 high yielding dairy cows were calculated from farm recording data and milk data record from a regular dairy control. Spearman rank correlation analysis was used to determine the correlation between reproductive parameters of the herd and the milk data record. In the time interval of 75–90 days postpartum the highest correlation was found between FPR and CC (r = 0.414, p < 0.05). Receiver operating characteristics (ROC) analysis was used to evaluate the FPR to distinguish between cows with different CC. The optimal cut‐off value at FPR of 1.34 provided the best discrimination power according to CC of 120 days. FPR at 1.44 enabled us 91.7% correct identification of cows with CC above 140 days, where the highest area under the ROC curve of 0.759 and likelihood ratio of 7.2 were observed. FPR ≤1.19 was 2.86 times as likely to be found in cows with CC below as in cows with CC above 90 days. The FPR has been shown to be of benefit in the prediction of reproductive efficiency in dairy herds.
Calcineurin inhibitors and post‐transplant weight gain
Authors: ERSOY ALPASLAN , BARAN BULENT , ERSOY CANAN , KAHVECIOGLU SERDAR , AKDAG IBRAHIM
Published: March 2008

Aim:  Excessive weight gain that leads to obesity is quite common after kidney transplantation. This is often attributed to immunosuppression. The aim of this retrospective study was to assess the effect of calcineurin inhibitors on post‐transplant weight gain.

Methods:  A total of 99 patients were studied. The patients were divided into cyclosporine A (CyA) and tacrolimus (Tac) groups and were evaluated for weight changes and risk factors related to weight gain.

Results:  The weights of patients in both groups significantly increased after the sixth month. The median weight gain at 12 months was 3.5 and 8.0 kg compared with pretransplant dry weight in the Tac and CyA groups, respectively. The increases in the CyA group were significant compared with those of the Tac group. The prevalences of obese and overweight patients in both groups did not differ during a 12‐month follow‐up. The frequencies of diabetes mellitus, hypertension and dyslipidemia were comparable in both groups. The decrease in systolic blood pressure (BP) of the Tac group was significant compared with the decrease in the CyA group at the 12th month. In the 12‐month follow‐up period, the increases in triglyceride, total‐ and low‐density lipoprotein‐cholesterol values of the CyA group were significantly higher than those of the Tac group. The weight change between 0 and 12 months was negatively correlated with pretransplant body mass index (BMI) and positively with cumulative corticosteroid doses, total‐cholesterol and BP changes.

Conclusion:  Only pretransplant BMI, creatinine clearance, CyA usage, being hypertensive and dysplipidemic were independent predictors of weight gain at the 12th month. Our results suggested that the type of immunosuppression may affect post‐transplant weight gain.
Anaemia in patients with chronic kidney disease: Management with epoetin beta in primary care setting in New Zealand
Authors: MADHAN KRISHAN K , CHAMBERLAIN MICHELLE , ANDERSON ELIZABETH
Published: March 2008

Aim:  Anaemia is a major complication of advancing chronic kidney disease (CKD) and is amenable to treatment with epoetin. In order to manage the large number of CKD patients, it is essential that much of the care take place in primary care practices.

Methods:  We describe a programme to treat anaemia with epoetin beta (EPO), using a simple referral and management protocol, by general practitioners remotely supported by a nephrologist and nurse coordinator team.

Results:  Data for 79 patients treated between May 2005 and May 2007 was analysed. Patients were treated with stepwise alterations of EPO dose, beginning with 4000 units/week, and were followed up for a mean of 11 months (range 3–25). The mean age was 73 years and 91% were of Caucasian origin. Sixty‐seven per cent had stage 4 CKD and 27% were at stage 3. Mean haemoglobin increased from 92.9 (standard deviation (SD) 7.1) to 118.5 (SD 11.7) g/L (P < 0.01). More than 75% achieved Hb of 110 g/L or more by the fifth month of therapy. Mean starting dose of EPO was 58.8 (SD 25.0) and increased to 79.9 (SD 55.6) units/kg/week (P < 0.01). Mean serum ferritin decreased (P = 0.05), but transferrin saturation was not significantly altered. Estimated glomerular filtration rate remained stable. There was non‐significant elevation of systolic and diastolic blood pressure during treatment.

Conclusion:  The study demonstrates that treatment of anaemia with EPO can be successfully accomplished in primary care setting by general practitioners without the need for many patients to attend a nephrology clinic.