Morphology and structural organization of gené's organ in Dermacentor reticulatus (Acari: Ixodidae).

Scanning and transmission electron microscopical investigations revealed that Genés organ in unfed and ovipositing females of Dermacentor reticulatus is formed as a double-sac-structure consisting of an outer epithelial and an inner cuticular sac. In ovipositing ticks the latter emerges through the camerostomal aperture to the exterior. Genés organ in unfed ticks consists of a corpus, two posterior horns and a pair of undeveloped glands at each side, which differentiate in ovipositing ticks to compound, branched tubular glands with a main efferent duct for each gland opening into the lumen between the epithelial and the cuticular sac. Genés organ of egg-laying females corresponds basically in morphology and structural organization to that of unfed ticks. Compared with unfed ticks, however, in ovipositing ticks the corpus and horns are longer and broader, the glands are fully developed and the cuticular sac is evertable. The epithelial sac as the outermost part of Genés organ is continuous with the hypodermis of the basis capituli and the scutum, arises at the camerostomal aperture, forms the corpus and the two blind-ending horns, passes into the epithelium of the main excretory ducts of the glands and envelops the cuticular sac. The cuticular sac passes into the cuticle of the basis capituli and the scutum, arises at the camerostomal aperture, is folded, expands into the horn tips and consists inwards of a smooth epicuticula and outwards of a fibrous endocuticula. Muscles originating from the scutum pass caudomedially through the epithelial sac and are inserted into the cuticular sac. The entire surface of the maximally everted cuticular sac is covered with an amorphous mass. In cleaned samples, ledge-like structures appear on the lateral surface. These ledges turn into balloon-like structures which extend over the medial and dorsal surface. The entire surface including the balloon-like structures and the ledges are provided with numerous cribrate pits.

Morphology and structural organization of Gene's organ in Argas walkerae.

Electron microscopy revealed that Gene's organ in females of Argas walkerae Kaiser & Hoogstraal (Ixodida: Argasidae) is formed as a double-sac structure consisting of an outer epithelial and an inner cuticular sac. The latter emerges through the camerostomal aperture to the exterior in ovipositing ticks. The epithelial sac forms the corpus and the two blind-ending horns, which pass into the epithelium of the excretory duct of a gland at each side of Gene's organ and envelop the cuticular sac. Both excretory ducts open into the lumen between the epithelial and the cuticular sac. The cuticular sac is folded and consists of a fibrous endocuticula outwards towards the lumen between the epithelial and the cuticular sac and of a smooth epicuticula inwards. Parallel running grooves occur over the lateral epicuticular surface turning medially into cobble-stone pavement-like rises. Tubuli pass through the cuticular sac ending in pores on the epicuticular surface and open into the lumen between the epithelial and the cuticular sac. Muscle fibres pass through the epithelial sac at the horn tips and are inserted to the cuticular sac. In ovipositing females, the glands are fully developed and the lumen between the epithelial and the cuticular sac is filled with an amorphous mass.

Chemotaxonomy of Plantago. Iridoid glucosides and caffeoyl phenylethanoid glycosides.

Data for 34 species of Plantago (Plantaginaceae), including subgen. Littorella (= Littorella uniflora), have been collected with regard to their content of iridoid glucosides and caffeoyl phenylethanoid glycosides (CPGs). In the present work, 21 species were investigated for the first time and many known compounds were found together with three new iridoid glucosides. Of these, arborescoside and arborescosidic acid, both of the uncommon type with an 8,9-double bond, were present in several species, while 6-deoxymelittoside was found only in P. subulata. The known compounds deoxyloganic acid, caryoptoside and rehmannioside D were isolated from the genus for the first time. The earlier reported occurrence of sorbitol in the family was confirmed, and this compound was shown by NMR spectroscopy to be the main sugar in the three species investigated for this. The combined data show that CPGs are present in all species investigated. With regard to the iridoids, the distribution patterns showed a good correlation with the classification of Rahn. Thus, aucubin is typical for the whole genus, while bartsioside and catalpol as well as 5-substituted iridoids are each characteristic for a subgenus in the family. Finally, the close relationship between Plantago and Veronica suggested by chloroplast DNA sequence analysis. could be corroborated by the common occurrence of the rare 8,9-unsaturated iridoids in these two genera.

Optical properties of Se2- and Se2 color centers in the red selenium ultramarine with the sodalite structure.

The unique optical properties of Se2- radicals located in the cages of the sodalite structure are reported. By means of luminescence, photoluminescence excitation, and absorption spectroscopy, three different centers are identified. Two of them are Se2- anions in sites with presumably a tetrahedral Na4(4+) coordination and a Na3(3+) environment with cation deficiency, respectively, giving rise to a red luminescence band with two different progressions. The third center is the intermediate Se2 molecule, created photochemically by UV laser excitation. It induces an additional blue luminescence. The electronic properties of the Se2- centers, particularly in the excited states, are significantly influenced by steric constraints imposed by the limited space in the sodalite host polyhedra. Thus, the sodalite structure can be viewed as a model system for studying effects of this kind on chromophores imbedded in the cages of the zeolite-type lattice.

Long-term follow-up after early intervention with intravenous diltiazem or intravenous nitroglycerin for unstable angina pectoris.

AIMS: In a double-blind randomized trial in unstable angina it was shown that intravenous diltiazem reduced ischaemic events in the first 48 h after inclusion better than intravenous nitroglycerin. The present study was performed to establish the long-term prognosis of the randomized patients, with respect to their initial treatment assignment. METHODS AND RESULTS: One year follow-up data on ischaemic end-points and anti-ischaemic medication were recorded. Results were available for all of the 121 randomized patients. One hundred and sixty-seven primary endpoint events were recorded, of which 54 occurred in the first 48 h and 113 during the follow-up. Survival analysis showed that event-free survival was significantly better in the diltiazem group (45.0%) than in the nitroglycerin group (34.4%), P=0.04. The incidence rate after 48 h and one year for cardiac death are, respectively, 0% and 4.1%. The trend in anti-ischaemic medication was higher in the nitroglycerin group. For beta-blockers, this trend became significant after 12 months (P=0.03). CONCLUSION: These results show that the initial benefit obtained by early treatment with intravenous diltiazem was preserved during the first year after the initial hospitalization, and that, despite the high risk of cardiac events in our population, the overall mortality 12 months after inclusion was low.

Morphology of the eyes in adult Hyalomma truncatum ticks (Acari: Ixodidae).

The eyes of Hyalomma truncatum ticks are morphologically similar in both sexes. They appear as paired hemispherical structures situated dorsally between the first and second pair of legs on the lateral scutal margin. Each eye consists of a lens and photoreceptor cells, which are separated by a fine fibrillar layer and the hypodermis. The lens contains numerous channels which open beneath the epicuticle, converge uninterruptedly to the interior of the lens and end below the fine fibrillar layer. The inner closure of the lens is formed as an oval plateau with a cone-like projection situated caudolaterally and eccentrically to the longitudinal axis of the lens. The hypodermis is a single layer of cells, situated immediately below the fine fibrillar layer. Beneath the hypodermis, directly below the cone-like projection of the inner lens are the photoreceptor cells localized in a rosette-like arrangement. Facing the hypodermis, each photoreceptor cell is provided with numerous microvilli. The microvilli consistently border the microvilli regions of other cells at different angles but are always oriented at a right angle to the lenticular channels. The photoreceptor cells are unipolar neurons, whose axons arise from the basal portion of the cell and join to nerve fibre bundles forming the optic nerve. It is concluded that the eyes in adult H. truncatum ticks possess all the structures necessary to perceive and conduct light stimuli and visual signals.

[Systemic availability of bovine immunoglobulin G and chicken immunoglobulin Y after feeding colostrum and whole egg powder to newborn calves]. / Zur systemischen Verfügbarkeit von bovinem Immunglobulin G und Hühner-Immunglobulin Y aus gefüttertem Kolostrum bzw. Volleipulver bei neugeborenen Kälbern.

In connection with a study on the prophylaxis of infectious diarrhea with specific egg yolk antibodies, the systemic availability of colostral bovine immunoglobulin G (bIgG) and chicken immunoglobulin Y (IgY) after feeding egg powder was investigated on 26 newborn calves from 23 different farms. Blood was sampled daily and at the same day time from these calves in the first 14 days of life. During the feeding of colostrum, the mean bIgG concentration was highest at day 1 post natum with a value of 9.3 mg/ml serum. Thereafter, the mean bIgG level was reduced continuously to a significant lower concentration of 4.9 mg/ml serum at day 12 post natum and remained nearly constant at 5.2 mg/ml till to the end of the observation period. Total protein concentrations in the serum did not change and plateaued at a mean value of 56.2 mg/ml (SD 11.2). The number of colostrum meals had no significant effect on the mean bIgG concentrations during that period. The individual variation of bIgG concentrations was very high on every day of the sampling period. The mean coefficient of variation was at 52.1 % (SD 5.7). After having described the individual bIgG concentration curves mathematically with a regression curve, two groups with significantly different bIgG elimination constants (k) could be obtained. Thus in one group (n = 10) with k-values of < -0.02 a mean half time of serum bIgG of 24.3 days (SD 4.6) was calculated. In the other group of calves (n = 16) with elimination constants of k > -0.02, a mean half time of 68.5 days (SD 36.7) could be calculated, possibly because these calves started earlier with their endogenous bIgG production. Additionally, to 18 of these calves 20 g egg powder with an IgY concentration of 15 mg/g was fed up to day 14. Calves had a maximal mean IgY concentration of 1.9 micrograms/ml serum if egg powder feeding started already during the first 12 hours of life. Starting at a later time resulted in a significant reduction of IgY levels. For example, the mean initial IgY concentration dropped to 0.035 micrograms/ml serum after having had the first egg powder application between 25 and 48 hours post natum. Using the individual IgY elimination constant derived from a regression analysis (r2 = 0.84) of the IgY concentration curve, a mean IgY half time of 5.0 days (SD 2.5) could be calculated. To prevent the absorption of heterologous antibodies and consecutively, also to prevent a possible systemic effect, egg powder for prophylactic purposes in newborn calves should be fed after the first 24, better 48 hour, post natum. Most important for the prophylactic effect of specific antibodies on infectious diarrhea is not their systemic but their high local intestinal availability.

[Endoparasites of donkeys and horses kept in communal housing in Upper Bavaria; species spectrum and incidence]. / Endoparasiten von Eseln und Pferden bei gemeinsamer Haltung in Oberbayern: Artenspektrum und Befallshäufigkeit.

In this epidemiological study of endoparasites 37 donkeys and 23 horses were included, which were examined coproscopically in regular intervals over a 15 month period. The animals derived from ten farms, in which regular prophylactic treatments with anthelmintics had been practiced at least for two years before this investigation. This study revealed the presence of at least twelve parasite species in donkeys, Eimeria leuckarti, Gasterophilus intestinalis, Fasciola hepatica, Anoplocephala perfoliata, Strongyloides westeri, Parascaris equorum, Dictyocaulus arnfieldi, Trichostrongylus axei and small strongyles, whose third stage larvae were characterized by eight, twelve, 16 or 18 intestinal cells. At least four parasite species were established in horses, E. leuckarti, G. intestinalis, P. equorum and small strongyles, whose third stage larvae were provided with eight intestinal cells. Infections with E. leuckarti, S. westeri and P. equorum were encountered in foals only and with D. arnfieldi in 16.2% of the donkeys. Incidences for small strongyles were highest, exhibiting neither age- and farm-dependent nor host species-dependent differences and amounting to 91.9% in donkey and 86.6% in horses. Considering all donkeys and horses, 35.1% and 43.5%, respectively, were infected at least with two, and 29.7% and 4.3%, respectively, with three parasite species. The species composition of the endoparasite fauna was always dominated by small strongyles. This field study indicates that the species composition of the endoparasite fauna in comparison to former investigations has not or only slightly changed in spite of widespread use of broad-spectrum anthelmintics for years. In addition, it has to be considered that donkeys continue to act as reservoir of D. arnfieldi and as source of infection for horses.

[Sarcocystis phoeniconaii n. sp. Murata, 1986 (Apicomplexa: Sarcocystidae) of the lesser flamingo (Phoeniconaias mirror: Ciconiiformes)]. / Sarcocystis phoeniconaii n. sp. Murata, 1986 (Apicomplexa: Sarcocystidae) des Lesser Flamingo (Phoeniconaias mirror: Ciconiiformes).

The tiny rice-grain like sarcocysts measure 3-5 x 1 mm, they are situated subfascially or in the depth of the muscles. The 50 nm thick irregular primary cyst wall forms towards the inside, small, bubble-like, less osmiophilic invaginations, which partly are concentrated in such a way, that a spongious like structure develops. The so surrounded protrusions are vertically or slightly inclined; they measure 4.25 x 1.7 microns and they are filled with compact fibrils. The cyst wall is underlaid by an average of 7.0 microns thick tape consisting of ground substance, from which an extensive septation runs to the center of the cyst. The so formed chambers are filled with lancet-like merozoites, which measure 15-20 x 1.8-2.5 microns. Their fine structure is identical with merozoites of all other sarcosporidia. A round vacuole, which is placed at the rear end of the merozoite near the nucleus seems to be a characteristic. Metrocytes are found rarely in the periphery and they are usually degenerated. In some cysts cystozoites, ground substance and protrusions show signs of lysis, the septation, however, remains usually unchanged.

[Spectrum of species and incidence of endoparasites in foals and their mother mares from breeding farms with and without anthelmintic prophylaxis in upper Bavaria]. / Artenspektrum und Befallshäufigkeit von Endoparasiten bei Fohlen und ihren Mutterstuten aus Zuchtbetrieben mit und ohne Anthelminthika-Prophylaxe in Oberbayern.

In this epidemiological study 37 foals and mares were included, which have been coproscopically examined in regular intervals over a period lasting up to 13 months. The animals derived from nine breeding farms. In three of these farms no anthelmintics were used before this investigation, whereas in six farms at least three years before regular prophylactic treatments with anthelmintics have been carried out. This investigation revealed no differences in the species spectrum of endoparasites as well as in the incidence of infections as regards to the breeding farms with and without anthelmintic prophylaxis, however, significant differences between foals and mares. At least nine species were established in foals, Strongyloides westeri in 54.1% of the animals, Parascaris equorum in 64.9%, small strongyles, whose third stage larvae showed either eight or 12 intestinal cells, in 83.8%, Anoplocephala perfoliata in 16.2%, Eimeria leuckarti in 64.9%, Giardia in 5.4%, Cryptosporidium parvum in 2.7% and Gasterophilus intestinalis in 21.6%. Parasitic infections with two or more species were found in 83.8% of the foals. The species spectrum of endoparasites in mares from breeding farms without anthelmintic prophylaxis consisted of at least three species of small strongyles, whose third stage larvae were characterized by eight, 12 or 16 intestinal cells. In mares from breeding farms practising regular anthelmintic prophylaxis, however, at least seven species were ascertained, the same small strongyles, P. equorum, A. perfoliata, E. leuckarti and G. intestinalis.

Randomised, double-blind trial of intravenous diltiazem versus glyceryl trinitrate for unstable angina pectoris.

The effect of dihydropyridines in patients with unstable angina is discouraging. To find out the effect of the non-dihydropyridine-like calcium-channel blocker diltiazem, a randomised, double-blind trial was conducted comparing diltiazem with glyceryl trinitrate, both given intravenously, in 129 patients with unstable angina. The endpoints were refractory angina or myocardial infarction, individually and as a composite endpoint. Refractory angina alone or together with myocardial infarction occurred significantly less commonly in the diltiazem group. While patients were on the trial drugs the numbers with refractory angina were 6 (10%) in the diltiazem group versus 17 (28%) in the glyceryl trinitrate group (relative risk 0.36, p = 0.02), and the numbers with refractory angina and myocardial infarction were 9 (15%) versus 23 (38%) (relative risk 0.40, p = 0.007). Over 48 h the number were: refractory angina 8 (13%) versus 18 (30%), relative risk 0.45, p = 0.03, and refractory angina and myocardial infarction 12 (20.0%) versus 25 (41%), relative risk 0.49, p = 0.02. Patients in the diltiazem group had better (p < 0.05) event-free survival while taking the drugs. Heart-rate pressure product was reduced significantly only by diltiazem (p < 0.05). The incidence of bradyarrhythmias did not differ significantly. Atrioventricular conduction disturbances occurred in 5 (8%) patients in the diltiazem group but were not seen in the glyceryl trinitrate group (p = 0.03). These disturbances could be reversed by decreasing the dose of the drug or withdrawing it. No temporary pacemakers were required. Headache requiring an analgesic or dose adjustment occurred significantly less in the diltiazem group: 3 (5%) versus 15 (25%), relative risk 0.20 (p < 0.004). These results indicate that intravenous diltiazem, compared with intravenous glyceryl trinitrate, significantly reduces ischaemic events and can be used safely in patients with unstable angina.

Long-term stable mode locking of a visible diode laser with phase-conjugate feedback.

We present a new method to obtain long-term stable phase-conjugate feedback (pcf) with a photorefractive crystal for a mode-locked semiconductor laser. The phase-conjugate mirror is a barium titanate crystal in a self-pumped internal reflection configuration, and the laser is a visible, antireflection-coated AlGaInP diode. We describe a new dynamic writing procedure for growth of an index grating in the photorefractive crystal that leads to stable pcf and discuss the reasons for this stability, which is the major advantage of this method over previously reported ones. Using this superior method, we achieve stable mode-locked operation of the laser with pulse widths of ~30 ps and a timing jitter of less than 2 ps.

Efficacy of metoprolol and diltiazem in treating silent myocardial ischemia.

Recent studies strongly support the prognostic importance of transient silent ischemia. Because patients with silent ischemia are at higher risk of a cardiac event, they are likely to benefit not only from control of symptoms, but also from treatment directed at prevention of ischemia. The efficacy of controlled-release metoprolol 200 mg once daily and diltiazem 60 mg 4 times daily was assessed in a randomized, double-blind, crossover study in 32 patients with proven coronary artery disease, predominantly asymptomatic myocardial ischemia, positive bicycle exercise test results, and > or = 5 minutes of asymptomatic ST-segment depression on a 24-hour screening ambulatory electrocardiogram (ECG). At the beginning and at the end of both 3-week treatment periods, an exercise test was performed and a 72-hour ambulatory ECG was recorded. Both active treatment periods were preceded by a 2-week placebo phase. Both treatments effectively reduced and postponed exercise-induced ST depression and reduced the total ischemic integral on the ambulatory ECG. Only metoprolol significantly reduced the mean number of ischemic episodes (54%, p = 0.0003, vs 31% for diltiazem, p = NS) and the mean duration of ischemia (51%, p = 0.012, vs 27% for diltiazem, p = NS) compared with baseline values. Metoprolol strongly blunted the morning and afternoon peak in the circadian distribution of ischemia, whereas diltiazem did not change the circadian distribution of ischemia at all.

[Fauna and incidence of endoparasites in kittens and their mothers from different husbandry situations in south Germany]. / Fauna und Befallshäufigkeit von Endoparasiten bei Katzenwelpen und ihren Müttern unterschiedlicher Haltung in Süddeutschland.

In this epidemiological study 100 litters of Southern Germany were investigated. 70 litters were kept on farms and 30 litters originated from mother cats kept indoors. At least 9 species were detected in litters from farms, 77.1% of these litters were infected with T. cati, 1.4% with hookworms, 10% with Capillaria, 10% with H. taeniaeformis, 67.1% with I. felis, 48.6% with I. rivolta, 17.1% with Toxoplasma/Hammondia, 4.3% with C. parvum and 1.4% with Giardia. In litters kept indoors only 5 species were established. 3.3% were infected with T. cati, 46.6% with I. felis, 33.3% with I. rivolta, 6.6% with Giardia and 3.3% with C. parvum. Analogous differences as regards to the keeping conditions existed also for the mother cats.

Mode locking using a type II multiple-quantum-well structure as a fast saturable absorber.

We demonstrate the application of a type II Al(x)Ga((1-x))As/AlAs multiple quantum well as a fast saturable absorber in a hybridly mode-locked dye laser. Type II multiple quantum wells are promising for this application because of the fast recovery of the saturated absorption with picosecond or even subpicosecond time constants. We obtain almost transform-limited pulses as short as 0.9 psec for a type II sample with a recovery time of 2.3 psec.

RFLP analysis of Zea mays callus cultures and their regenerated plants.

Tissue culture of the Zea mays inbred line A188 resulted in the regeneration of plants having a high level of phenotypic variation compared to seed-grown control plants. To determine how such variation was induced and whether this could be related to specific in vitro culture methods, callus cultures were established and maintained on different, commonly used culture media. Plants were regenerated and the genomic DNA of callus cultures and regenerants analysed for RFLP differences. The results show that regardless of the gene probe used, callus formation resulted in significant deviations from the DNA pattern normally found in seed-grown control plants. Alterations in gene copy number also occurred. As differentiation and organogenesis began, the level of DNA variation fell, and most of the regenerated plants showed a genetic similarity to the controls; those with RFLP differences were the somaclonal variants.