Zeitschrift fur Parasitenkunde (Berlin, Germany)最新文献

The immunofluorescent antibody test and immunocytochemical method were employed to study the surface antigens of Angiostrongylus cantonensis obtained from infected rats, mice and guinea pigs. Positive results with intense fluorescence and brownish peroxidase staining were observed on the cuticular surface of A. cantonensis recovered from rats 22 days (late cerebral phase) and 34 days (lung phase) post-infection when tested with antisera against host (normal rat serum) antigens as well as crude extracts of A. cantonensis. However, host antigens were not observed on the surface of the nematode recovered from the brain of mice and guinea pigs 15 days post-infection.

Bloodstream forms of nine different Trypanosoma vivax stocks were compared by the enzyme ratios of selected enzyme systems. Analysis of the results differentiated the trypanosome stocks into three groups, thus suggesting that enzyme ratios of selected enzymes could be of practical use in demonstrating intraspecific differences in trypanosomes.

Effects of gamma-ray irradiation on the first-stage larvae of Angiostrongylus cantonensis were studied. There was a significant reduction in the infectivity of the 10,000 R-irradiated larvae to intermediate host snails compared to other groups. In the final host infection, both the worm populations and worm body length of irradiated groups differed markedly from those of the non-irradiated control.

Trace elements in two species of whale tapeworms, Diphyllobothrium macroovatum and Diplogonoporus balaenopterae, were analysed by atomic absorption spectroscopy. Six elements (Fe, Cu, Zn, Mn, Cd, Ca) were assayed from different regions of two tapeworms: scolex, neck, immature, mature and gravid proglottids. Whole strobilae at different stages of maturity were also examined. The relationship between the trace element content and the physiological significance is discussed.

Culture-derived Litomosoides carinii microfilariae (MFF) were used in in vitro and in vivo systems to investigate the effect of diethylcarbamazine (DEC) on these MFF. In vivo: Male rats, Mastomys natalensis, all of the same age, were injected intrathoracically (12) or intraperitoneally (36) with 10(3) or 10(4) MFF. After 30 min one half of each group of rats was given DEC per os. At 30, 60, and 120 min after DEC administration, two rats from the treated and two from the untreated group were bled and killed. The pleural or peritoneal cavities were rinsed with warm saline (0.15 M NaCl) to recover MFF. In both the intrathoracic and intraperitoneal experiments, equal numbers of MFF were recovered from treated and control rats at 30 and 120 min. However, at 60 min 85.5% fewer were recovered from the treated than from the nontreated animals. MFF were not found in the blood. In vitro: MFF were added to tissue culture dish wells (Linbro Div., Flow Labs, Hamden, Conn) prepared as follows: DEC-Serum (serum from normal rats given DEC at 500 mg/kg), DEC + Serum (serum with added DEC), serum only, RPMI 1640 only, and RPMI 1640 + DEC. Furthermore, the five treatments were prepared either with or without unstimulated peritoneal exudate (PE) cells. At 30 min in the DEC-Serum wells 45% of the MFF had adherent PE cells; in the remaining wells these cells adhered to 11% or fewer MFF. We interpret the aforementioned phenomena as representing the first step in the trapping and elimination of MFF after DEC treatment of L. carinii-infected M. natalensis.

Of one hundred placentas collected consecutively in the Ubangi district, Zaire, 64 had falciparum malaria. Mothers and infants of the 64 malarious and 36 non-malarious placentas were compared. The malarious placentas had no consistent relationship to infant length or head circumference, APGAR score, birthweight, maternal anemia, splenomegaly or hydramnios. The rate of hydramnios, in fact, was higher in the mothers with non-malarious placentas. Mothers with malarious placentas were younger (means 24) than mothers with non-malarious placentas (means 29). Mothers with fewer pregnancies were more likely to have malarious placentas than older multiparous mothers. There were 7 stillbirths, 4 from mothers with malarious placentas. Infants born to mothers with malarious placentas averaged 100 g less than those from mothers with non-malarious placentas. This study shows that mothers with falciparum malaria from the Ubangi district deliver normal and apparently unaffected infants.

The process of interaction of bloodstream trypomastigotes from the myotropic CL and Colombiana strains and the macrophagotropic Y strain of Trypanosoma cruzi with mouse myoblasts and myotubes was analysed. After 24 h of parasite-host cell interaction, parasites from the CL and Colombiana strains appeared to be more infective to myoblasts than those from the Y strain. Parasites from the Colombiana strain were more infective for myotubes than those from the Y strain, while those from the CL strain showed very a low ability to infect the cells. For all strains the infectivity was low for short periods of interaction, increasing with time. Myoblasts infected with parasites from the Y strain fused with other infected and uninfected cells to form myotubes. However, the process of fusion was blocked when the myoblasts were infected with parasites from the CL and Colombiana strains. These data indicate a different behavior of muscle cells when in contact with myotropic or non-myotropic strains of T. cruzi.

The histology of male and female Litomosoides carinii was studied in serial sections. The body wall of the female worm consists of a rather thin cuticle, very extended lateral hypodermal chords and small sectors of shallow coelomyarian muscle cells. In the female worm an intestinal lumen is found, which is filled with material throughout the worm's length. Both ovaries are situated close to the posterior end. In both genital tubes all stages of oogenesis and embryogenesis could be observed in approximately equal stages of development in most of the sections. The lateral chords of the male worm are very small, whereas the somatic muscle cells are large and of the circomyarian type. The intestine is a minute tube beside the much thicker testis and vas deferens. Considerable sexual dimorphism could be observed in almost all organs of adult Litomosoides carinii.

By intravenous (i.v.) inoculation of living tuberculosis bacteria (BCG) non-specific resistance to microfilariae of Litomosoides carinii (Filarioidea) is induced in cotton rats. This is only possible using the preparation "Immune-BCG Pasteur F" (suspended germs), but not with "Vaccin-BCG pour scarifications" (lyophilized tuberculosis bacteria). After inoculation of Immune-BCG, followed by a challenge infection by 60 infective larvae 6 weeks later, a patent infection develops. However, the level of microfilaraemia is constantly lower than in the control. After challenge infection 12 weeks later, this effect has disappeared. Immune-BCG has no influence on the worm load or the output of microfilariae by the adult worms. If i.v. inoculation of Immune-BCG is combined with a subcutaneous injection of specific antigen--living embryos from the uteri of adult worms--the BCG-activated immune system undergoes specific sensitization. Upon challenge infection 6 weeks later, the microfilaraemia is completely suppressed, but the worm load and production of microfilariae by the adult female worms are normal. If Immune-BCG is injected i.v. 3 days before intraperitoneal injection of freeze-killed microfilariae, there is still constantly reduced microfilaraemia when challenge infection follows 12 weeks later. Obviously, the effect of this relatively weak antigen may be increased by BCG stimulation.