The efficacy of neem seed extracts (Tre-san, MiteStop on a broad spectrum of pests and parasites.

The paper summarizes the acaricidal and insecticidal effects of a patented neem seed extract when diluted 1:10 with shampoo or 1:20, 1:30, 1:33, 1:40, respectively, 1:66 with tap water. It was shown that a broad range of pests and parasites, such as house dust mites, poultry mites, harvest mites, Ixodes and Rhipicephalus ticks, cat fleas (adults, larvae), bed bugs (all stages), head lice and mallophaga, cockroaches (genera Blatta, Blattella, Gomphadorhina), raptor bugs (Triatoma), and even food-attacking beetle (Tenebrio molitor) might be controlled with this extract, which is available as Tre-san (against house dust mites) and MiteStop (against mites, ticks, insects of any kind) to become water diluted or as Wash Away Louse or Picksan LouseStop being diluted in a shampoo. Tests on skin compatibility proved that there are no skin irritations during or after use. However, some target species are less sensible (beetles, Triatoma stages, fly maggots), while the specimens of the other species cited above were successfully killed even at low concentrations of the extract.

Effects of permethrin (Flypor) and fenvalerate (Acadrex60, Arkofly) on Culicoides species-the vector of Bluetongue virus.

Bluetongue disease struggles ruminants in Europe since summer 2006, introducing high levels of morbidity and mortality. Besides vaccination, the application of insecticides is another means to protect cattle and sheep from infections with the Bluetongue virus, which is transmitted in Europe by female specimens of Culicoides species (Culicoides obsoletus and in a few cases of Culicoides pulicaris and Culicoides dewulfi). The present study deals with the effects of permethrin (Flypor) and fenvalerate (Arkofly, Acadrex 60) on freshly caught Culicoides specimens when brought into contact for 15, 30, 60 or 120 s with hair of cattle or sheep treated topically 7,14, 21, 28 or 35 days before. The experiments clearly showed that the lege arte application of these compounds (products) onto the hair of the experimental animals succeeds in killing Culicoides specimens when brought into contact with hair from feet of animals being treated even 35 days before. This test was needed to make sure that the products do reach the feet and belly of the animals in sufficient amounts, since this region is the predominant biting site of the Culicoides midges.

Pilot study on deltamethrin treatment (Butox 7.5, Versatrine) of cattle and sheep against midges (Culicoides species, Ceratopogonidae).

Deltamethrin (Butox 7.5, Versatrine)-treated hair of cattle and sheep were brought into contact for 15, 30, 60, or 120 s with freshly caught Culicoides specimens, which are the vectors of the Bluetongue virus. The hair was clipped off from the treated animal just above the claws-a region which is one of the predominant biting sites of the midges. Hair obtained on day 7, 14, 21, 28, or 35 after treatment were mingled with the Culicoides specimens for the given contact periods. After separation of the midge from the hair and placing them onto white filter paper in a petri dish, their fate was followed for the next hours by microscopic inspection. It was found that deltamethrin (in both formulations Butox, Versatrine) reaches for 35 days in such sufficient amounts in the hair of the legs to kill attacking specimens of Culicoides in reasonable short periods after very short contacts. The observed speed of kill and the deleting effects were so quick that the midges very probably would not bite before their death.

Outbreak of bluetongue disease (BTD) in Germany and the danger for Europe.

In August 2006, the blue tongue virus (BTV-type South Africa serotype 8) was detected for the first time in cattle blood probes in the Netherlands, immediately followed by cases in Belgium and in cattle on German farms, which were situated close to Aachen at the border to those countries. Within less than 2 months the disease spread eastwards crossing the Rhine, southwards to Luxemburg and to Northern France. At the end of the year 2006, nearly 1,000 farms were affected in Germany. Catches on two German cattle farms proved that the ceratopogonid species Culicoides obsoletus was obviously the vector, since many females-fed and unfed ones-were found to be infected with this virus. This sudden outbreak of bluetongue disease (BTD) is surely not a primary result of global warming, but rather an effect of globalization-i.e. the intensive worldwide import and export of animals; but a hot summer, as in 2006, and a warm winter like that of the years 2006/2007 supported the new spread starting again in masses in August 2007 leading to 596 PCR-confirmed cases until then with more than 200,000 animals infected. Thus, new agents coming from elsewhere have only a chance to spread if appropriate vectors are available and the conditions remain favourable during a reasonably long period. Effects of global warming-of course-will support persistence of such outbreaks of diseases due to offering of spreading of imported viruses, bacteria and/or parasites.

Efficacy of Oxyfly on Culicoides species--the vectors of Bluetongue virus--and other insects.

The efficacy of the insecticide Oxyfly (active compound lambda-cyhalothrin) was tested against specimens of Culicoides species-the vectors of Bluetongue virus-and other insects. Living specimens of the insects were brought into contact for at least 10-15 s with treated wooden plates and the extinction period of the insects was followed over the next minutes or hours. It turned out that this rather short contact was sufficient to kill the Culicoides specimens in minutes and the other insects in a few hours even if the plates had been impregnated 9 weeks before.

What are the infectious larvae in Ascaris suum and Trichuris muris?

In the present study, larvae of Ascaris suum and Trichuris muris were investigated by light and electron microscopy after incubation in a hatching medium containing 89% phosphate-buffered saline (pH 7.4), 10% RPMI-1640 and 1% sodiumhypochlorite at 40 and 37 degrees C, respectively. The larvae were obtained from fertilised eggs of the worms during defined phases of development (A. suum, 36th-50th day of development; T. muris, once a week from week 16 to 20). Light and electron micrographs of the larvae gave evidence that the third larval stage of A. suum is probably the infectious stage. The first moult of the larvae had already taken place before the 36th day of incubation starting at day 1. After 36 days of incubation, only the second larval stage was found within eggs. Some of these larvae were coated by a separated sheath so that a second moult of the larvae is reasonable. On the other hand, no sheathed larvae of T. muris were found in the eggs incubated for 20 weeks in distilled water. No signs of moult were seen for 20 weeks neither on light nor on the electron micrographs. Therefore, in T. muris, the first larval stage is the infectious stage, which was proven by means of re-infections of mice 16, 18 or 20 weeks after incubation of the eggs.

Butox 7.5 pour on: a deltamethrin treatment of sheep and cattle: pilot study of killing effects on Culicoides species (Ceratopogonidae).

Topical treatment (at the neck and along the vertebral column) with deltamethrin (Butox 7.5 pour on) of cattle (30 ml/400-kg body weight) and sheep (10 ml/60-kg body weight) was done to find out, whether the insecticide may reach in a sufficient dosage the legs, which are known to be the main biting site of Culicoides specimens that are the vectors of the recently introduced Bluetongue virus in central Europe. At days 7, 14, 21, 28, and 35 after treatment, some hair was cut off from the legs--close to the claws. Freshly (the night before) caught Culicoides obsoletus specimens were then exposed for 15, 30, 60, or 120 s to such hair and afterwards transferred to a filter paper within plastic Petri dishes to observe their fate. It turned out that even a short contact of 15 s of the Culicoides specimens with deltamethrin-treated hair of cattle or sheep was sufficient to paralyze and kill Culicoides specimens within a reasonable short time even when the hair were cut off at day 28 after treatment. While the results obtained in cattle and sheep were rather similar for days 7 and 14 after treatment, the speed of the killing effect of treated hair of cattle on Culicoides considerably slowed down beginning from day 21 after treatment. However, all the experiments clearly showed that the insecticide deltamethrin may reach the feet of cattle and may kill Culicoides specimens when the product is poured along the vertebral column. Such a treatment may considerably reduce the risk of transmission of the agents of disease. However, in the case of the thick fleece of sheep, the insecticide must be poured directly into the skin to reach full activity.

Effects of Bayofly on specimens of Culicoides species when incubated in hair taken from the feet of previously treated cattle and sheep.

Sheep and cattle were treated with Bayofly pour-on containing 1 g cyfluthrin per 100 ml ready-to-use solution. Seven, 14, 21 and 28 days after treatment, hair was clipped off from the back and feet and mixed for 10-15 s, 30 s, 1 or 2 min with freshly caught Culicoides midges. It was found that the insecticide on hair from the legs--the predominant biting site of midges--had a significant killing effect on Culicoides for 3-4 weeks, even after a short-term contact.

Direct images of the virtual source in a supersonic expansion.

Direct images of the virtual source in a supersonic expansion of helium are presented. The images were obtained using a Fresnel zone plate with free-standing zones, 540 microm in diameter and with an outermost zone width of 50 nm. The general method can be extended to other beams, including seeded beams. Measurements were carried out at absolute source pressures ranging from 11 to 171 bar using a 10 microm nozzle with a source temperature of 320 K. The size of the virtual source was found to be strongly dependent on pressure, changing from a diameter of 67+/-6 microm at an absolute nozzle pressure of 11 bar to 180+/-9 microm at 171 bar. The virtual-source brightness displays a maximum at an absolute nozzle pressure of around 30 bar. This phenomenon occurs because of two competing effects: As the pressure increases, the total flux also increases, but at the same time the virtual source broadens. We modeled the expansion process by calculating the velocity distribution with solutions from the Boltzmann equation to estimate the location of the quitting surface where the frequency of interatomic collisions is assumed negligible. Realistic potentials have been used to calculate the cross section for atomic collisions and, for the velocity distribution perpendicular to the center streamline, a proper scaling with distance derived from the continuum expansion model has been introduced. A good agreement between experiments and model has been found and we discuss its approximation limits. For instance, backscattering effects are not included in the calculations and at present we cannot exclude that they also contribute to a broadening of the virtual-source size for the highest pressure regime. The results presented here are important for improving the understanding of the supersonic expansion process. The experimental method might eventually be used as a new way to test molecular and atomic interaction potentials.

Parasite fauna of the bank vole (Clethrionomys glareolus) in an urban region of Germany: reservoir host of zoonotic metazoan parasites?

In the present study, 29 bank voles (Clethrionomys glareolus) were studied for their endo- and ectoparasite fauna. The rodents were trapped in Dormagen, a city in North Rhine-Westphalia, Germany. A total of ten different parasite species were identified: four endoparasite (four Nematoda) and six ectoparasite (three Insecta, three Arachnida) species. The predominant endoparasite was the nematode Aonchotheca murissylvatici, followed by the nematode Heligmosomum costellatum, while the flea Ctenophthalmus agyrtes was the dominant ectoparasite. C. glareolus usually carried one to five different parasite species (mean 2.2). The bank voles were infected only by Nematoda, while Digenea or Cestoda species were not detected. The present findings are in clear contrast to the results obtained in other geographical regions of Germany and Europe, where eight different Cestoda species constituted the main part of the helminth parasites in C. glareolus. In the area investigated, the bank voles harbored no zoonotic parasites, and therefore, they play not a role as potential reservoir host for these parasite species.

Light and electron microscopic studies on two nematodes, Angiostrongylus cantonensis and Trichuris muris, differing in their mode of nutrition.

The morphological characteristics of the adult heteroxenous blood nematode Angiostrongylus cantonensis and the adult monoxenous intestinal nematode Trichuris muris were compared with special regard to the ultrastructure of their digestive systems. The small circular mouth of A. cantonensis appears sucker like. The very narrow mouth of T. muris is surrounded by three lips covered by the cuticle that extends into the buccal space. In the buccal cavity of A. cantonensis, a single tooth occurs opposite to a cutting plate, while no teeth are present in T. muris. The lumen of the well-developed muscular pharynx of A. cantonensis shows a trifurcated star-like cross-section. The anterior segment of the bipartite pharynx presumably functions as a pump. The lumen of the bipartite pharynx and esophagus of T. muris exhibits a very narrow oval cross-section and possesses no musculature. It is composed of a long column of stichosome cells. The esophagus region is lined inside by bands of bacillary cells as well as outside by two longitudinal rows of funnel-like papillae. These structures may be involved in the uptake of nutrients by T. muris. The gland cells might excrete digestive exoenzymes, while the bacillary cells take up the predigested nutrients. The presence of many vesicles suggests a vesicular transport of the material into the pharynx. The intestinal epithelium of A. cantonensis is densely covered with short microvilli. The lumen itself is filled with red blood cells originating from host blood. The intestine of T. muris has a thick epithelium being placed on a basal lamina and shows long thin microvilli. The intestinal lumen is very narrow and free from particles or granules. This again suggests that T. muris lives on low molecular nutrients resorbed from the environment. The epithelium cells of the intestine of T. muris contain glycogen and electron light granules but are lacking mitochondria. This finding may indicate that the epithelium cells have an anaerobic energy metabolism. This statement fits with the fact that the habitat of the worm, the cecum, is largely anaerobic.

Parasites of two abundant sympatric rodent species in relation to host phylogeny and ecology.

In the present study, two abundant sympatric rodent species (27 Apodemus flavicollis and 33 A. sylvaticus) were studied for their endo- and ectoparasite fauna. The rodents were trapped in Dormagen, a city in North Rhine-Westphalia, Germany. A total of 20 different parasites species were identified, 13 endoparasite (2 Digenea, 5 Cestoda and 7 Nematoda) and 7 ectoparasite (5 Insecta and 2 Arachnida) species. Thirteen parasite species were found inhabiting both rodent species. The predominant endoparasite species in both rodents was the nematode Pelodera strongyloides, followed by the nematode Heligmosomoides polygyrus and a Syphacia species. The flea Ctenophthalmus agyrtes was the dominant ectoparasite in both rodent species. A. flavicollis usually carried 1-7 ecto-/endoparasite species (mean 4.0), whereas A. sylvaticus were mostly infested with 1-9 (mean 4.4). The parasite diversity of A. flavicollis (H' = 0.268, J = 0.097) was marginal lower in comparison to A. sylvaticus (H' = 0.319, J = 0.110). The two rodent species examined show remarkable similarities in the composition of their endo- and ectoparasite fauna being directly related to their similar pattern of living in the investigated area.

Extract of the seeds of the plant Vitex agnus castus proven to be highly efficacious as a repellent against ticks, fleas, mosquitoes and biting flies.

About 70 plant extracts were tested for their ability to repel the attacks of blood-sucking arthropods. It was found that a CO2 extract of the seeds of the Mediterranean plant Vitex agnus castus (monk's pepper) can be used as a spray to keep away especially Ixodes ricinus and Rhipicephalus sanguineus ticks from animals and humans for at least 6 h. In addition mosquitoes, biting flies and fleas are also repelled for about 6 h.

Growth and characterisation of primary bovine colon epithelial cells in vitro.

Epithelial crypts from the bovine colon were obtained by using a combined mechanical and enzymatic isolation method, followed by differential D-sorbitol gradient centrifugation. By using this isolation technique, a pure fraction of epithelial crypts with minimal mesenchymal contamination was obtained. The crypts were seeded in collagen-coated plastic flasks. The attached epithelial cells proliferated and formed a confluent monolayer after 6 days in culture. Under low-serum culture conditions (1% fetal calf serum), the cells had a population doubling time of 21-22 hours. During the culture period, the colonocytes were characterised morphologically and enzymatically. The morphology of the cultured cells was confirmed by scanning electron microscopy and transmission electron microscopy. The presence of microvilli, tight junctions and desmosomes demonstrated the ability of the cultured cells to restore an epithelial-like cell monolayer. The epithelial origin of the cells was demonstrated by labelling the cells with antibodies against epithelial-specific cytokeratins 7 and 13. The functional integrity of the cells was evaluated by measuring various marker enzymes (gamma-glutamyltranspeptidase, acid phosphatase, alkaline phosphatase, NADH-dehydrogenase) and membrane-associated Na+-K+-ATPase activity. Membrane integrity was determined by measuring the leakage of lactate dehydrogenase into the culture medium. This new culture system for bovine colon epithelial cells could be used as an in vitro model of the colon epithelium in physiological and toxicological studies.

Activities of drug metabolizing enzymes in bovine colon epithelial cell cultures.

The metabolic competence of cultured bovine colon epithelial cells was evaluated by determining activities of phase I and II enzymes in colonocytes cultured for different intervals (maximum of 10 days) compared with activities measured in freshly isolated cells. Cytochrome p50 1A1-associated 7-ethoxyresorufin O-deethylase (EROD) activity was detectable in freshly isolated colonocytes and in colon cells maintained in culture for up to 5 days. In contrast to liver samples, cytochrome p50 3A4-associated 7-benzyloxyresorufin O-debenzylase (BROD) activity was not detectable in bovine colon cells. Prostaglandin H synthase-mediated production of prostaglandin E(2) was found in freshly isolated and also in cultured colonocytes. Both isoenzymes (COX 1 and COX 2) were detected in cultured cells. To examine phase II metabolic potency, activities of N-acetyltransferases 1 and 2, of phenol and amino sulfotransferases, of glutathione S-transferases alpha, mu, pi and theta and of UDP-glucuronyltransferase were measured. N-Acetyltransferase (NAT) activity (substrate p-aminobenzoic acid, PABA, a diagnostic substrate for the human NAT-1 enzyme) was stable under culture conditions and during the observed culture period comparable to that of freshly isolated cells. In contrast, sulfamethazine, a specific substrate for NAT-2, was not acetylated, neither in bovine colon cells nor in bovine liver samples. Whereas activity of amino sulfotransferase (substrate 2-naphthylamine) decreased continuously during the entire culture period, the activity of phenol sulfotransferase (substrate 1-naphthol) decreased only slowly. Activity of total glutathione S-transferases (alpha, mu, and pi) (substrate 1-chloro-2,4-dinitrobenzene) decreased after 2 days in culture, but was stable during the following culture period. Activity of glutathione S-transferase theta (substrate epoxy-3-nitrophenoxypropane) changed during the culture period. At the beginning and the end (after 10 days) of the culture period maximum activity was measured. Activity of UDP-glucuronyltransferase increased during the culture period reaching a maximum after 7 days. The results show that cultured bovine epithelial colon cells express several enzyme activities required for the biotransformation of xenobiotics.

Genome function and nuclear architecture: from gene expression to nanoscience.

Biophysical, chemical, and nanoscience approaches to the study of nuclear structure and activity have been developing recently and hold considerable promise. A selection of fundamental problems in genome organization and function are reviewed and discussed in the context of these new perspectives and approaches. Advancing these concepts will require coordinated networks of physicists, chemists, and materials scientists collaborating with cell, developmental, and genome biologists.

Effects of orally administered chemotherapeutics (quinine, salinomycin) against Henneguya sp. Thelohán, 1892 (Myxozoa: Myxobolidae), a gill parasite in the tapir fish Gnathonemus petersii Günther, 1862 (Teleostei).

When given orally, quinine or salinomycin cause irreversible damage to the plasmodial developmental stages of Henneguya sp., a gill parasite in the tapir fish Gnathonemus petersii. Naturally infected tapir fish measured 75-169 mm in total length and their total weight ranged over 4.3-11.7 g. The fish bore 7-77 plasmodia in their gill arches. Medicinal food containing either quinine (5 g/1000 g food) or salinomycin (0.075 g/1000 g food) was given once a day to naturally infected fish in a food chain via water fleas ( Daphnia spp) for a period of 3, 6, or 9 days. From the monitored feeding of the tapir fish and weight determinations of the water fleas, it was calculated that gross uptake was 18.5 micro g/kg body weight fish daily for pure salinomycin and was 1.25 mg/kg body weight daily for quinine. After the end of the experiments, the fish were sacrificed and the plasmodia were carefully prepared from the gill arches and processed for transmission electron microscopy. As seen by ultrastructure investigations, for both substances the grade of damage in the parasites correlated positively with the period of application. When quinine was given for a 3-day period, the trophozoite ecto- and endoplasm exerted numerous vacuoles, caused by the drug, and the presporogonous and the pansporoblastic stages were malformed. Following a 6-day period, numerous abortive polar capsules were found in the trophozoite cytoplasm. To a large extent, the limiting membranes of the polaroblasts and valvogenic cells were destroyed. In addition, deep clefts between the polaroblasts, the valvogenic cells and between the two sporoblasts were observed. Following a 9-day treatment, all damage increased and, in addition, generative cells and two-cell stages were no longer detectable. As a first sign for the effects of salinomycin, following a 3-day treatment, a shrinking of the whole plasmodia occurred and the sutures in the pansporoblasts were enlarged. The polar capsules were malformed and the zonar structures of the polar filament were no longer detectable. The sporoplasmosomes were more electron-pale than those of the control samples. After a 9-day treatment, the pansporoblasts were completely destroyed. Under the experimental conditions chosen, both compounds were very well tolerated by the fishes.