| biomphalaria glabrata: influence of calcium, lectins, and plasma factors on in vitro phagocytic behavior of hemocytes of noninfected or schistosoma mansoni-infected snails. | in vitro phagocytosis of erythrocytes by hemocytes of b. glabrata, intermediate host of s. mansoni, is strongly influenced by calcium, several lectins, and plasma factors. our results indicate that two different mechanisms of non-self-recognition in b. glabrata may occur: (1) in the presence of calcium, phagocytosis occurs in noninfected and in infected snails without involvement of any other substances, and hemocytes of schistosome resistant as well as those of susceptible snails are able to re ... | 1992 | 1639158 |
| identification of a schistosoma mansoni sporocyst excretory-secretory antioxidant molecule and its effect on superoxide production by biomphalaria glabrata hemocytes. | excretory-secretory (e-s) products obtained during in vitro schistosoma mansoni miracidium-to-sporocyst transformation were found to contain a 108-kda polypeptide capable of scavenging both exogenously produced and m-line biomphalaria glabrata hemocyte-derived superoxide (o2-) anions. separation of crude transformation e-s products using hplc and ion exchange chromatography resulted in the separation of two isoforms of the 108-kda molecule. using an in vitro phagocytosis assay, both isoforms wer ... | 1991 | 1664845 |
| schistosoma mansoni: identification of chemicals that attract or trap its snail vector, biomphalaria glabrata. | a new bioassay for chemical attractants of aquatic snails demonstrated that biomphalaria glabrata could be attracted to or trapped in the vicinity of homogenates of lettuce. fractionation of homogenates revealed the amino acids glutamate and proline and the primary attractants. attraction was specific for the l form of glutamate. proline appeared to stimulate reproductive activity. glutathione, gamma-aminobutyric acid, and a number of other compounds had no effect. extracts of lyophilized snail ... | 1978 | 684418 |
| schistosoma mansoni: use of a cloned ribosomal rna gene probe to detect restriction fragment length polymorphisms in the intermediate host biomphalaria glabrata. | adult susceptibility of biomphalaria glabrata to schistosoma mansoni infection is controlled by simple mendelian genetics. in this study a molecular approach was used to determine the degree of genetic variation between well-defined lines of b. glabrata which are either resistant (10-r2) or susceptible (m-line) to s. mansoni infection. a cloned probe psm389, which contains part of the s. mansoni small ribosomal rna gene and a portion of the nontranscribed spacer was found to cross-hybridize with ... | 1991 | 1680745 |
| the suitability of several aquatic snails as intermediate hosts for angiostrongylus cantonensis. | sixteen species of aquatic snails of four families were tested by quantitative technique under standardized conditions for their suitability as intermediate hosts for angiostrongylus cantonensis. these species were the planorbid snails biomphalaria glabrata, biomphalaria alexandrina, planorbis planorbis, planorbis intermixtus, bulinus truncatus, bulinus contortus, bulinus africanus, bulinus tropicus and helisoma sp.; the lymnaeid snails lymnaea natalensis, lymnaea tomentosa, lymnaea stagnalis, a ... | 1975 | 1189583 |
| the effect of some biological and physical factors on infection of biomphalaria glabrata with angiostrongylus cantonensis. | several biological and physical factors which may influence infection of biomphalaria glabrata snails with the first stage larvae of angiostrongylus cantonensis were studied. these factors were: the size of snails, the number of first stage larvae to which snails were exposed, the age of larvae, individual exposure compared with mass exposure of snails, the length of exposure period and the effect of temperature and light. the results showed that young snails, 2 mm in diameter, became infected w ... | 1975 | 1189582 |
| isolation and functional characterization of snail hemocyte-modulating polypeptide from primary sporocysts of schistosoma mansoni. | infection with larval trematodes has been shown to inhibit several snail-host defences, including hemocyte phagocytosis, cytotoxicity, motility, and adherence. certain plasma factors which mediate snail defence responses, and which may be produced by host hemocytes, also appear to be altered by these parasites. in this study we present protocols for the isolation of 2 proteins from larval schistosoma mansoni excretory-secretory (es) products and detail the effects of these components on biomphal ... | 1991 | 1775150 |
| genetic factors in susceptibility of biomphalaria glabrata for different strains of schistosoma mansoni. | biomphalaria glabrata selected for genetic differences in susceptibility to infection with a puerto rican strain of schistosoma mansoni were exposed to miracidia of a strain of s. mansoni from st lucia. the st lucian strain was less infective than the puerto rican. results suggested that in snails susceptible to the puerto rican s. mansoni differences in susceptibility to the st lucian straing were determined by a single gene, with insusceptibility dominant. | 1975 | 1128925 |
| the occurrence of schistosomin, an antagonist of female gonadotropic hormones, is a general phenomenon in haemolymph of schistosome-infected freshwater snails. | in haemolymph of lymnaea stagnalis, parasitized with the digenetic trematode parasite trichobilharzia ocellata, a neuropeptide (schistosomin) occurs which antagonizes female gonadotropic hormones, e.g. calfluxin (cafl). by means of an ultracytochemical hormone-assay, the cafl assay, it was demonstrated that the occurrence of schistosomin is a general phenomenon in schistosome-infected freshwater snails. haemolymph of the schistosomiasis-transmitting snail species biomphalaria glabrata and b. pfe ... | 1991 | 1780174 |
| superinfection of biomphalaria glabrata with schistosoma mansoni. | biomphalaria glabrata 2 to 12 mm in diameter were exposed to 1 miracidium of schistosoma mansoni and after 15, 30, or 60 days were reexposed to the homologous strain. the criterion of superinfection was the subsequent escape of cercariae of both sexes. opposite sex superinfection was acquired by 45 of 106 snails of various sizes, all of which were in the group reexposed at 30 days. the observations confirm those of kagan and geiger and suggest that in the schistosomes a maximizing of the number ... | 1975 | 1117376 |
| displacement of biomphalaria glabrata by thiara granifera under natural conditions in the dominican republic. | after a study of the population dynamics of biomphalaria glabrata snails in several breeding places in the dominican republic, the snail thiara granifera was introduced in some b. glabrata habitats. t. granifera became established in one point in one habitat in the town of quisqueya, in the east of the country. around this point of establishment 6 points were selected in order to observe the population dynamics of both species of snails and the chemical and biological characteristics at each poi ... | 1991 | 1842424 |
| [identification of a new focus of schistosoma mansoni. (municipality of nova lima, mg, brazil]. | the detection of a new transmission focus of schistosomiasis in nova lima town, minas gerais state, brazil, is reported. the search of snail intermediate hosts in banqueta do bananal a small locality of boa vista neighbourhood detected 356 specimens of biomphalaria glabrata, with a infection rate of 8.4%. in hundred-sixty-two patients stool examinations (kato-katz method) were done, showing ninety-one patients with eggs of schistosoma mansoni in their feces. the integrated action of local reside ... | 1991 | 1842844 |
| selective depletion of hemolymph proteins of biomphalaria glabrata infected with schistosoma mansoni. | | 1975 | 1117358 |
| [repopulation of breeding habitats of biomphalaria glabrata after treatment with niclosamide]. | experiments were undertaken both in the laboratory and in the field between 1980-1984 to evaluate the causes of repopulation of breeding places of biomphalaria glabrata following treatment with niclosamide. laboratory bioassays showed that the susceptibility to emulsifiable niclosamide of b. glabrata collected monthly from an irrigation ditch system varied during the year. lethal concentrations (lc90) ranged between 0.15 mg/l-1 and 0.60 mg/l-1. statistically significant differences (alpha = 0.01 ... | 1991 | 1844951 |
| variations in infectivity for biomphalaria glabrata in strains of schistosoma mansoni from the same geographical area. | genetic differences in infectivity for intermediate snail hosts in two strains of s. mansoni from the same geographical area and within a single isolated parasite population are reported. the importance of recognizing the potential for such genetic variation is stressed. | 1976 | 1088517 |
| effect of manganese on biomphalaria glabrata infected with schistosoma mansoni. | | 1976 | 977981 |
| lectin-binding properties of the surfaces of in vitro-transformed schistosoma mansoni and echinostoma paraensei sporocysts. | as carbohydrates on the surfaces of sporocysts of digenetic trematodes may be targets of attack by the molluscan internal defense system, the lectin-binding patterns of living, in vitro-transformed sporocysts of schistosoma mansoni and echinostoma paraensei were characterized. schistosoma mansoni sporocysts specifically bound 8 and e. paraensei 6 of 11 lectins examined. sporocysts of the 2 species responded differently to 7 of the 11 lectins. lectins inhibitable by mannose, galactose, and n-acet ... | 1991 | 1919922 |
| influence of the nontarget mollusc marisa cornuarietis on the hourly cercarial production of schistosoma mansoni from biomphalaria glabrata. | a comparative study of hourly cercarial productivities of schistosoma mansoni from infected biomphalaria glabrata was carried out in the presence of either healthy b. glabrata (control) or healthy marisa cornuarietis (experimental). the results showed that, with m. cornuarietis, almost all the hourly cercarial productivities increased by a factor varying from 1.3 to 2.5 without modification of the shedding period. | 1991 | 1919935 |
| intermediate hosts of schistosoma mansoni in brazil. | the brazilian planorbidical chart is slowly but progressively been increased by new data. distribution of vector species of schistosoma mansoni, according to paraense, 1986, may be thus resumed: biomphalaria glabrata--delimited by parallels 13 and 21 degrees s and meridians 39 and 45 degrees w, area of greater dominance (southeast bahia, oriental hal of minas gerais and espírito santo). it is observed along the coast line of the states of sergipe, alagoas, pernambuco, paraiba and rio grande do n ... | 1992 | 1343914 |
| [principal factors involved in the settlement of biomphalaria glabrata (say, 1818), snail intermediate host of schistosomiasis in guadalupe (author's transl)]. | six biotopes of biomphalaria glabrata, the snail intermediate host of schistosomiasis in guadalupe, were investigated during one annual cycle. these six biotopes included a pond, a freshwater mangrove, a stream, a mountain lake, a "microhabitat" and a canal. these six types of biotopes were characterized by various parameters whose fluctuations reveal the main factors regulating the b. glabrata populations. the climatic factors are essential in grande terre and resulted in an annual development ... | 1977 | 921191 |
| miracidium of schistosoma mansoni: a macromolecular glycoconjugate as signal for the behaviour after contact with the snail host. | 1. the behaviour of the miracidium of schistosoma mansoni after contact with agar blocks containing biomphalaria glabrata snail conditioned water (scw) or its components, was studied. 2. "repeated investigation" was the most specific response at contact with the snail host. 3. fractionation and specific chemical treatment of scw revealed that this response was stimulated by a lysozyme sensitive glycoconjugate with a mol. wt greater than 300,000. 4. low molecular weight components of scw had no s ... | 1992 | 1348464 |
| ecdysteroids as regulators of host and parasite interactions: a study of interrelationships between schistosoma mansoni and the host snail, biomphalaria glabrata. | ecdysteroids have been detected in trematode parasites and in several species of gastropod snails. the potential role of these and other hormones as regulators of host/parasite interactions is discussed. this study considers the role of ecdysteroids in the host parasite interactions between schistosoma mansoni and biomphalaria glabrata interactions. beta-ecdysterone was found to be effective in stimulating host location activities in s. mansoni miracidia and in enhancing growth and egg productio ... | 1991 | 2052849 |
| responses of echinostoma caproni miracidia to gravity, light, and chemicals. | in a four-tube vertical system, echinostoma caproni miracidia exhibited a strong negative geotaxis which was dominated by a positive phototaxis. in horizontal chambers a positive phototactic response was also demonstrated. these miracidia showed a positive chemoresponse, as determined in phi-chambers, to glutamic and aspartic acids but not leucine. positive responses were also elicited to snail-conditioned water and sulfuric and acetic acids. ammonia, mg2+, and hcl produced no significant reacti ... | 1992 | 1399253 |
| structural homology of tropomyosins from the human trematode schistosoma mansoni and its intermediate host biomphalaria glabrata. | molecular mimicry has been considered as a possible way for parasites to escape host immune responses. this work concerns the characterization of protein determinants shared by schistosoma mansoni and its intermediate host biomphalaria glabrata. parasite (sm39) and mollusc (bg 39) cross-reactive proteins were identified and shown to induce in rabbit and mouse, antibodies specific for invertebrate determinants. ultrastructural studies demonstrated that antibodies to sm39 specifically bound to mus ... | 1990 | 2090946 |
| molluscicidal acridone alkaloids from angostura paniculata: isolation, structures, and synthesis. | two novel acridone alkaloids, cuspanine [1] and cusculine [2], were isolated from the ch2cl2 extract of the leaves of angostura paniculata (rutaceae). their structures were established as 1-hydroxy-2,3,5,6-tetramethoxy-9-acridone for 1 and 1,2,3,5,6-pentamethoxy-9-acridone for 2 by means of spectroscopic studies, in particular nmr. these structural assignments were confirmed by synthesis, using a direct metallation method as a key reaction. both alkaloids exhibited moderate molluscicidal activit ... | 1992 | 1431935 |
| schistosoma mansoni infection in diapausing biomphalaria glabrata snails: studies of temperature and genetic influences on diapausing behavior. | snails that are capable of undergoing diapause can circumvent unfavorable environmental conditions, including long periods of drought. studies were performed to investigate possible temperature and/or genetic factors that may trigger lamella formation and diapausing behavior. the influence of diapause in biomphalaria glabrata snails on susceptibility to schistosoma mansoni infection and levels of cercarial production was also investigated. rearing temperatures of 23 degrees c or higher did not i ... | 1992 | 1443349 |
| lectin binding to cells of schistosoma mansoni sporocysts and surrounding biomphalaria glabrata tissue. | the binding of different lectins to the surface of mother and daughter sporocysts of schistosoma mansoni (trematoda) and to cells of its intermediate host biomphalaria glabrata (gastropoda) was investigated. the test system consisted of several biotin-labeled lectins, an avidin-biotin-peroxidase complex and 3,3'-diaminobenzidine. the fixatives used were formalin, bouin's and zenker's solutions; unfixed material was also studied. most lectins reacted equally with host tissue and parasite tissue. ... | 1990 | 2105357 |
| influence of intramolluscan larval stages of echinostoma liei on the infectivity of schistosoma mansoni cercariae. | during co-infection of biomphalaria glabrata with schistosoma mansoni and echinostoma liei, s. mansoni cercariae released before the complete resorption of s. mansoni sporocysts show a very strong decrease of their infectivity in mice. under conditions of high interspecific competition (i.e. when the snails are infected by e. liei 8 days after infection by s. mansoni), the mean overall worm return is five times lower than that of the control experiment. a marked decrease of the infectivity of ce ... | 1990 | 2110945 |
| dynamics of the leukocytic response of biomphalaria glabrata during the larval development of schistosoma mansoni and echinostoma liei. | the daily evolution of the number of hemocytes in biomphalaria glabrata was ascertained under three conditions: uninfected snails, snails infected with schistosoma mansoni, and snails infected with echinostoma liei. the results show differences between the three experiments as well as in the average hemocyte density over the whole experimental period, as in the temporal dynamics of circulating hemocyte number. specifically, it appears that the development of e. liei in b. glabrata induces a dens ... | 1990 | 2112576 |
| [molluscacide and cercariacide activity of different species of eucalyptus]. | hydrolates and essential oils of several eucalyptus species were tested on adult snails and egg masses of biomphalaria glabrata, and cercaria of schistosoma mansoni. these products were obtained by vapor dragging. eight out of 21 hydrolates presented activity on snails, nine on egg masses and three on cercaria at 1:4 dilutions. eleven oils were active on both snails and egg masses at 20 ppm concentrations. the hydrolate of e. deanei was active both on snails, egg masses and cercaria at 1:4 dilut ... | 1990 | 2133583 |
| in vitro effect of larval schistosoma mansoni excretory-secretory products on phagocytosis-stimulated superoxide production in hemocytes from biomphalaria glabrata. | the in vitro production of the reactive oxygen metabolite superoxide (o2-) was confirmed in hemocytes from the schistosome intermediate host biomphalaria glabrata. active forms of the enzyme superoxide dismutase (sod) inhibited reduction of nitroblue tetrazolium (nbt) to formazan in cells that had phagocytozed zymosan particles, whereas an inactivated form of sod did not. moreover, based on the prevalence of o2(-)-positive hemocytes and the relative intensity of nbt staining reactions, hemocytes ... | 1990 | 2174969 |
| biological control of the snail intermediate hosts of schistosoma mansoni in martinique, french west indies. | in martinique water-cress beds constituted the last transmission sites for schistosomiasis. the competitor snail, melanoides tuberculata, was introduced at the beginning of 1983 to a group of water-cress beds and eliminated the snail hosts, biomphalaria glabrata and b. straminea, in less than two years. following this first success, m. tuberculata was introduced to the other groups of beds which were inventoried at the beginning of the eighties. at the present time, b. glabrata and b. straminea ... | 1992 | 1519033 |
| spatial and energy compromise between host and parasite: the biomphalaria glabrata-schistosoma mansoni system. | the development of a sporocyst infrapopulation of schistosoma mansoni within the biomphalaria glabrata snail is, from a spatial point of view, detrimental to the host's digestive-genital gland complex growth. for mono- and plurimiracidial infections, the digestive gland volumes are, respectively 51 and 24% of those of control snails. identical reduction of the infected genital gland volume (43% of controls) occurs in both cases. after the prepatent period, the ratio of parasite/digestive gland v ... | 1992 | 1563925 |
| predation and control of laboratory populations of the snail biomphalaria glabrata by the freshwater prawn macrobrachium rosenbergii. | laboratory experiments were conducted on predation by the giant freshwater prawn, macrobrachium rosenbergii, on biomphalaria glabrata, a snail intermediate host of human schistosomiasis. prawns greater than 22 mm carapace length could consume snails of any size. smaller prawns exhibited a size-specific upper limit on the size of snail they could kill. below the maximum size of prey consumed, little selectivity for prey size was demonstrated. all prawns heavier than 2.5 g killed the largest size ... | 1990 | 2260905 |
| schistosoma mansoni infections in neonatal biomphalaria glabrata snails. | in areas endemic for schistosomiasis, the population dynamics of the snail intermediate hosts have a direct effect on parasite transmission. the present study focused on the potential for neonatal biomphalaria glabrata snails to become infected with schistosoma mansoni and to produce cercariae under various conditions. it was found that snails as small as 0.74 mm in shell diameter could survive miracidial penetration and could release cercariae when as small as 1.6 mm in diameter. cercariae prod ... | 1992 | 1597786 |
| the encapsulation process in biomphalaria glabrata experimentally infected with the metastrongylid angiostrongylus cantonensis: enzyme histochemistry. | | 1975 | 1206232 |
| immunoelectrophoretic study on common antigens of são lourenço da mata and belo horizonte strains of schistosoma mansoni adult worms and biomphalaria snails. | immunoelectrophoretic studies on common antigens were carried out by using rabbits sera immunized against são lourenço da mata and belo horizonte strains of schistosoma mansoni adult worms and antigens of biomphalaria glabrata pigmented (jaboatão--pe); b. glabrata albino (belo horizonte--mg) and b. straminea (são lourenço da mata, pe). furthermore, the reverse approach was proceeded, namely, sera anti biomphalaria snails produced in rabbits were tested against both strains of schistosoma adult w ... | 1992 | 1284896 |
| immunosuppression in the definitive and intermediate hosts of the human parasite schistosoma mansoni by release of immunoactive neuropeptides. | evidence supporting the concept that the parasitic trematode schistosoma mansoni may escape immune reactions from its vertebrate (man) or invertebrate (the freshwater snail biomphalaria glabrata) hosts by using signal molecules it has in common with these hosts was obtained by the following experiments. the presence of immunoactive proopiomelanocortin (pomc)-derived peptides [corticotropin (acth), beta-endorphin] in, and their release from, s. mansoni was demonstrated. coincubation of adult worm ... | 1992 | 1309957 |
| single and multiple worm infections of echinostoma caproni (trematoda) in the golden hamster. | six of 10 hamsters fed a single metacercarial cyst of echinostoma caproni (single-worm infections) and 13 of 19 hamsters fed either 2 or 5 cysts (multiple-worm infections) were infected with adult echinostomes at necropsy 22 days post-infection. considerable histopathological changes to the small intestine occurred in hamsters carrying single-worm infections. there were no differences in either mean length, width or wet weight of echinostomes in single- versus multiple-worm infections. the mean ... | 1990 | 2338486 |
| a comparative study of hemocytes from six different snails: morphology and functional aspects. | hemocytes taken from six different gastropod snails, achatina achatina, a. fulica, biomphalaria glabrata, bulinus natalensis, helix aspersa, and lymnaea stagnalis, were compared for morphology, peroxidase activity, and, using methods developed for l. stagnalis, the ability to generate reactive oxygen inermediates upon phagocytic stimulation. numbers of hemocytes per milliliter hemolymph and hemocytes' microscopical morphology showed some variation among the snail species. peroxidase activity was ... | 1992 | 1311738 |
| a laboratory study of the toxicity of the butanol extract of endod (phytolacca dodecandra) on two species of freshwater fish and two species of aquatic snails. | the purpose of this study was to evaluate the toxicity of the butanol extract of endod (phytolacca dodecandra) on 4 species of aquatic animals. groups of 10 mosquito fish (gambusia affinis) and 8 bluegill (lepomis macrochirus) were exposed to the butanol extract of endod in 300 ml of water at concentrations of 0.0, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.2 or 2.0 ppm. groups of 10 tropical snails (biomphalaria glabrata) and 10 pond snails (physa spp) were also exposed to the crude extract in 5 ... | 1990 | 2353429 |
| carbohydrate-binding plasma proteins from the gastropod biomphalaria glabrata: strain specificity and the effects of trematode infection. | as lectins are believed to mediate non-self-recognition in molluscs, carbohydrate-binding proteins (cbp) from the circulating plasma of the gastropod biomphalaria glabrata were harvested by affinity chromatography using six different monosaccharides as ligands. pools of plasma were derived from b. glabrata of either the m line strain, which is susceptible to infection with the pr1 strain of the digenetic trematode schistosoma mansoni, or from the 13-16-r1 strain, which is resistant to infection. ... | 1992 | 1330758 |
| [the susceptibility of planorbidae from the metropolitan area of belo horizonte, mg (brazil) to angiostrongylus costaricensis (nematoda, angiostrongylidae)]. | biomphalaria glabrata (control), b. tenagophila and b. straminea from our laboratory colonies iniciated with molluscs collected in the municipality of belo horizonte, mg (brasil), were experimentally infected with first-stage larvae of angiostrongylus costaricensis. the number of molluscs of each species exposed was 139, 77 and 149. about 25 days later, surviving molluscs were individually examined by artificial digestion. of 87 b. glabrata examined, 62 (71.3%) were positive and between one and ... | 1992 | 1342102 |
| natural infection of wild rodents by schistosoma mansoni. parasitological aspects. | the evaluation of the role of rodents as natural hosts of schistosoma mansoni was studied at the pamparrão valley, sumidouro, rj, with monthly captures and examination of the animals. twenty-three nectomys squamipes and 9 akodon arviculoides with a schistosomal infection rate of 56.5% and 22.2% respectively eliminated a great majority of viable eggs. with a strain isolated from one of the naturally infected n. squamipes, we infected 75% of simpatric biomphalaria glabrata and in 100% of albino mu ... | 1992 | 1343794 |
| excretory-secretory products of echinostoma paraensei sporocysts mediate interference with biomphalaria glabrata hemocyte functions. | miracidia of echinostoma paraensei were cultured in medium containing 14c-labeled amino acids, allowed to transform into sporocysts, and their excretory/secretory products (e-s) were collected and characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis and autoradiography. effects of e-s on hemocytes of biomphalaria glabrata were also assessed. e-s collected during day 1 of culture (e-s1) contained several polypeptides, none of which were labeled, suggesting that e-s1 are larg ... | 1992 | 1738052 |
| thermal preferences of resistant and susceptible strains of biomphalaria glabrata (gastropoda) exposed to schistosoma mansoni (trematoda). | the thermal preferences of two strains of the snail biomphalaria glabrata, one resistant to, and one susceptible to, the parasite schistosoma mansoni were determined in an aquatic thermal gradient. snails were tested without exposure to the parasite, and 2 h and 5 weeks after exposure to trematode miracidia. the mean temperature selected by susceptible strain snails 2 h post-exposure tended to be lower than that of unexposed controls, although this was not statistically significant. in this stra ... | 1991 | 1780172 |
| schistosoma mansoni shares a protective oligosaccharide epitope with freshwater and marine snails. | the expression of similar antigenic determinants by trematode parasites and their intermediate (invertebrate) or definitive (vertebrate) hosts has been previously reported. studies of experimental and human infection by the parasite schistosoma mansoni have revealed the strong immunogenicity of a surface antigen with a relative molecular mass (mr) 38,000 (38k). here we provide evidence that the important protective epitope of the 38k molecule is expressed by the uninfected intermediate host of s ... | 1986 | 2429191 |
| widespread antigenic cross-reactivity between plasma proteins of a gastropod, and its trematode parasite. | evidence obtained earlier with immunofluorescence and immunoelectron microscopy was interpreted to imply molecular mimicry of the host biomphalaria glabrata by the parasite schistosoma mansoni. using western blotting, we find that "mimicry" is due to widespread shared epitopes. furthermore, at least one individual plasma protein of b. glabrata shares epitopes with the majority of plasma proteins in the mollusc. the widespread antigenic determinants may be carbohydrates. caution is warranted when ... | 1987 | 2442042 |
| schistosoma mansoni antigens recognized in biomphalaria glabrata hemolymph by monoclonal antibodies. | in order to identify and characterize schistosoma mansoni antigens in biomphalaria glabrata, we examined 19 murine monoclonal antibodies (mabs) for specific binding to schistosome larvae. none of the murine mabs induced by infection or by immunization with a crude cercarial antigen (cca) served this purpose. two mabs out of 9 (kcsme22-3 and kcsme22-4) induced by soluble egg antigens reacted with cca but not with normal snail (nsn) extract. we selected these 2 for studies on detection and charact ... | 1989 | 2472748 |
| gp38, p28-i and p28-ii: candidates for a vaccine against schistosomiasis. | three antigens protective against schistosoma mansoni have been extensively characterized. the schistosomulum surface antigen gp38 possesses an immunodominant carbohydrate epitope of which the structure has been defined. protection can be achieved via the transfer of monoclonal antibodies recognizing the epitope or by immunization with anti-idiotype monoclonal antibodies. the glycan epitope is shared with the intermediate host, biomphalaria glabrata as well as being present on other molluscs, in ... | 1987 | 2474122 |
| biological control of biomphalaria glabrata and b. straminea by the competitor snail thiara tuberculata in a transmission site of schistosomiasis in martinique, french west indies. | in martinique, intestinal schistosomiasis was discovered at the beginning of this century. the intermediate host snail, biomphalaria glabrata, was considered in the past as a common species in the different habitats of the island, but during the last decade it has been found only in water-cress beds. several of these water-cress cultures contained mixed populations of b. glabrata and b. straminea. moreover, these habitats also constituted transmission sites for schistosoma mansoni infection. in ... | 1989 | 2513787 |
| [resistance to desiccation of biomphalaria glabrata adults infested by various miracidia of schistosoma mansoni]. | 1200 adult biomphalaria glabrata were submitted during 6 weeks to anhydrobiosis condition. some snails were healthy, some were previously infected 3 days or 12 days ago with 8 +/- 2 miracidia of schistosoma mansoni, others were shedding cercariae. the snails were put on soil or buried into hermetically closed, or ventilated, plastic boxes. there was no survival of snails kept in sealed boxes, or among positive snails, but 44% of control healthy snails and 40.6% of infected (for 3 or 12 days) sna ... | 1989 | 2517564 |
| [natural infection of wild rodents by schistosoma mansoni]. | in planalto, a small locality in the interior of the bahia state, brazil, 47% of sylvatic rodents were found to be naturally infected with schistosoma mansoni, whereas the prevalence of the infection in the inhabitants of the area was 3.26%. the rodents (nectomys) live near the houses, in contact with water, passing viable schistosome eggs in the stools. worm burden is variable amongst such rodents. periovular granulomas are small, especially in liver and intestines, and hepatic fibrosis is mild ... | 1989 | 2517565 |
| a potential vector of schistosoma mansoni in uruguay. | susceptibility experiments were carried out with a biomphalaria straminea-like planorbid snail (biomphalaria aff. straminea, species inquirenda) from espinillar, near salto (uruguay), in the area of the salto grande reservoir, exposed individually to 5 miracidia of schistosoma mansoni (sj2 and bh2 strains). of 130 snails exposed to the sj2 strain, originally infective to biomphalaria tenagophila, 30 became infected (23%). the prepatent (precercarial) period ranged from 35 to 65 days. the cercari ... | 1989 | 2520826 |
| [relationship between the pathogenicity of schistosoma mansoni in mice and the susceptibility of the vector mollusc. i. cercariae infectivity and worm burden]. | the possible influence of the immune mechanisms of the molluscs on the development of the sporocysts and the resultant behavior of the adult worm in the vertebrate host were studied. two strains of schistosoma mansoni (bh and sj) were used. these were genetically selected for their susceptibility and maintained, respectively, in biomphalaria glabrata and biomphalaria tenagophila, the natural invertebrate hosts. experimental groups of mice infected with cercariae proceeding from the two species o ... | 1991 | 1820625 |
| [effects of eugenol and derivatives on biomphalaria glabrata]. | biomphalaria glabrata snails and egg-masses were exposed, for six to twenty-four hours to concentrations of 1, 10, 100 and 1000 ppm of eugenol, o-methyleugenol, o-benzyleugenol and dehydrodieugenol. only at 10 ppm o-benzyleugenol enhanced mortality of snails and egg-masses. the other substances showed ovicidal and molluscicidal activity only at 100 and 1000 ppm concentrations, causing a significant cardiac frequency reduction in snails after 6 to 24 hours of exposure as well as perduring low car ... | 1991 | 1844101 |
| miracidia of schistosoma japonicum: approach and attachment to the snail host. | schistosoma japonicum miracidia swim directed along a chemical gradient toward the snails oncomelania hupensis and biomphalaria glabrata, and they turn back when the concentration of attractive chemicals decreases. the host signal for this chemotactic response has a molecular weight of more than 30,000. when swimming miracidia encounter the surface of o. hupensis or agar containing o. hupensis snail-conditioned water (scw) they perform the host-specific responses "contact with return," "repeated ... | 1991 | 1865256 |
| physiologic studies of snail-schistosome interactions and potential for improvement of in vitro culture of schistosomes. | despite extensive efforts to develop suitable media for rearing the intramolluscan stages of schistosomes, successful in vitro culture of these parasites remains elusive. recent 31p nmr studies demonstrated that the levels of free phospholipids, particularly phosphatidylcholine, in the digestive gland of the snail, biomphalaria glabrata, were dramatically reduced when the host was infected with schistosoma mansoni. it was speculated that absorption of host phosphatides may be an important source ... | 1991 | 1869492 |
| hemocyte production in trematode-infected lymnaea truncatula. | in trematode-infected lymnaea truncatula, as in other lymnaeids, hemocytes are formed in the connective tissue. mitoses are found singly in blood vessels or connective tissue or occur in hemocyte nodules, developing along the mantle epithelium or associated with blood sinuses. the so-called hemocyte-producing organ in l. truncatula is not equivalent to that in biomphalaria glabrata, but rather involves the proximal part of the kidney sac. it has a dual structure: the main part, containing podocy ... | 1991 | 1924255 |
| schistosoma mansoni: influence of infection on levels of translatable mrna and on polypeptide synthesis in the ovotestis and albumen gland of biomphalaria glabrata. | larval trematode infection causes a disruption of normal reproductive activity in the molluscan intermediate host. because relatively little is known about the dynamics of this host-parasite interaction, the effect of schistosoma mansoni infection on translatable mrna pools and on polypeptide synthesis was examined in the ovotestis (ot) and albumen gland (ag) of biomphalaria glabrata. total rna was isolated from ots and ags from uninfected control snails and snails at 14, 21, and 28 days postinf ... | 1991 | 2026214 |
| opsonization of yeast by the plasma of biomphalaria glabrata (gastropoda): a strain-specific, time-dependent process. | phagocytosis of yeast by haemocytes of biomphalaria glabrata, intermediate host of schistosoma mansoni, is influenced strongly by host plasma components, although it can occur without involvement of such factors. plasma from two strains of b. glabrata which are resistant to s. mansoni differs in its opsonic properties from the plasma of a susceptible strain. this may reflect the principles which determine compatibility or incompatibility in this host-parasite system. opsonization is a time-depen ... | 1989 | 2671868 |
| tegumental surface modulation in schistosoma mansoni primary sporocysts in response to ligand binding. | the clearance of host molecules from the surface of a parasite constitutes a potential immune evasive strategy. the possibility that certain ligands, when bound to the tegument of schistosoma mansoni primary sporocysts, could induce such a modulating effect was investigated. live, in vitro cultured primary sporocysts were first treated with either snail host biomphalaria glabrata plasma, an anti-sporocyst monoclonal antibody (moab iii-1), or concanavalin a (con a). the capacity of these primary ... | 1991 | 2052402 |
| alterations in hemolymph components in biomphalaria glabrata during long-term infection with schistosoma mansoni. | total protein, hemoglobin, glucose, and urea concentrations in hemolymph of biomphalaria glabrata were studied during a 12-week infection of the snails with schistosoma mansoni. the results suggest an equilibrium between host and parasite metabolism, which is reached after about 6 weeks of infection. during the period studied, the protein spectrum of infected snails showed no difference in quality compared with that of noninfected snails; all fractions were present, and no additional fractions a ... | 1989 | 2710775 |
| effects of infection with echinostoma paraensei on the circulating haemocyte population of the host snail biomphalaria glabrata. | circulating haemocytes from echinostoma paraensei-infected m line biomphalaria glabrata snails, or from age- and size-matched control snails, were studied on plastic slides with phase-contrast optics. granulocytes, hyalinocytes, and round cells were consistently present; granulocytes were further categorized as 'fully spread' (fs) or 'partially spread' (ps). among control snails, the relative percentage and estimated number/mm3 of round cells declined significantly with increased snail size, and ... | 1989 | 2717217 |
| a comparison of the glycolipid compositions of cercarial and adult schistosoma mansoni and their associated hosts. | glycolipid patterns of cercarial and adult schistosoma mansoni were determined and compared with those of biomphalaria glabrata snails and mouse (balb/c strain) red blood cells by high-performance thin-layer chromatography. differences in glycolipid content were found between cercariae and adult worms and between these stages and their respective host tissues. | 1990 | 2074137 |
| schistosoma rodhaini: dynamics and cercarial production for mono- and pluri-miracidial infections of biomphalaria glabrata. | no significant difference in cercarial production was noted when biomphalaria glabrata from brazil were exposed to one or several miracidia of schistosoma rodhaini from burundi, even though the dynamics seemed different. the minor differences can be explained by the intramolluscal larval development of this parasite characterized by the production of a high number of daughter sporocysts over a long period. | 1989 | 2738384 |
| identification of snails infected with schistosomes by elisa employing monoclonal antibodies: schistosoma mansoni in laboratory snails (biomphalaria glabrata) and in field snails (biomphalaria pfeifferi) from kenya. | an enzyme-linked immunosorbent assay (elisa) employing monoclonal antibodies was used for detecting schistosoma mansoni antigens in hemolymph of laboratory snails (biomphalaria glabrata) in kenya. infected laboratory snails shedding cercariae were differentially identified by elisa from uninfected snails with 100% sensitivity and specificity. prepatent infections were detected by elisa from 2 weeks after exposure to miracidia. thus, elisa revealed infection 3 weeks before maximal patency was rea ... | 1989 | 2742038 |
| influence of larval schistosomes on polysaccharide synthesis in albumin glands of biomphalaria glabrata. | an in vitro bioassay was used to examine [14c]glucose incorporation into polysaccharides in albumen glands (ags) of susceptible m-line biomphalaria glabrata infected with the nmri strain of schistosoma mansoni. polysaccharide and galactogen synthesis were unaffected by larval trematode infection in ags of snails at days 14, 21, and 28 post-infection (p.i.) when compared to uninfected controls. further experiments were conducted to determine if daughter sporocysts, hypothesized to be primary medi ... | 1990 | 2092292 |
| effect of temperature on the reproduction of the snail biomphalaria glabrata. | 1. the reproduction of the snail biomphalaria glabrata, one of the intermediate hosts of schistosoma mansoni, was evaluated under laboratory conditions by measuring egg production, number of ovipositions, number of eggs per oviposition, and hatching rate using a latin square design with five different temperature treatments. this permitted the elimination of occasional variation in oviposition due to manipulation or a priori group. 2. egg production and spawning rates were higher at temperatures ... | 1990 | 2095294 |
| preliminary observations on a hemolymph factor influencing the infectivity of schistosoma mansoni miracidia. | it has been demonstrated that the infectivity of schistosoma mansoni miracidia for a highly susceptible strain of biomphalaria glabrata was reduced markedly when the miracidia were pretreated with hemolymph from the snail helisoma caribaeum. although the helisoma hemolymph factor(s) responsible for this phenomenon has not been identified with certainty, it appears to be a snail lectin associated with binding sites for n-acetyl-d-glucosamine on the surface of the miracidium. hemolymph from uninfe ... | 1986 | 2872788 |
| effects of infection with angiostrongylus cantonensis on the circulating haemocyte population and the haematopoietic organ of the host snail m-line biomphalaria glabrata. | the number of circulating haemocytes, the size of the haematopoietic organ, and the size of haemocyte capsules around the parasite were studied in m-line biomphalaria glabrata snails exposed to 100 or 400 first-stage larvae of angiostrongylus cantonensis. the number of haemocytes in exposed snails increased significantly at 1 day post-exposure, decreased to control value, and then increased again. the decrease in number of circulating haemocytes is probably due to the removal of cells from the c ... | 1990 | 2230034 |
| molluscicidal and antischistosomal activities of zingiber officinale. | experiments were conducted to study the major constituents of zingiber officinale responsible for its molluscicidal activity and the effect of the active component on different stages of schistosoma mansoni. gingerol and shogaol exhibited potent molluscicidal activity on biomphalaria glabrata. gingerol (5.0 ppm) completely abolished the infectivity of schistosoma mansoni miracidia and cercariae in b. glabrata and mice, respectively, indicating that the molluscicide is capable of interrupting sch ... | 1990 | 2236291 |
| schistosoma mansoni and its intermediate host biomphalaria glabrata express a common 39 kilodalton acidic protein. | two schistosoma mansoni proteins of 43 and 39 kda (sm43 and sm39) were shown to react with rabbit antibodies produced against biomphalaria glabrata proteins. two-dimensional gel electrophoresis of miracidial proteins indicated that sm43 and sm39 were acidic proteins (pi 4.8 and 4.9 respectively) and were in vitro translated from miracidial messenger rna in the same molecular forms. sm43 and sm39 were expressed by all parasite stages of s. mansoni. using anti-sm43 and anti-sm39 mouse sera, we dem ... | 1989 | 2911278 |
| praziquantel treatment of biomphalaria glabrata infected with schistosoma mansoni--influence on snail fecundity. | praziquantel, administered over a 72 h period in the food of mature biomphalaria glabrata harbouring 7-week-old schistosoma mansoni infections, dramatically reduced the numbers of cercariae shed. doses of 20-30 micrograms/g body weight (including shell weight) reduced shedding by 85-95% over 5 weeks before recovery was evident. suppression of cercarial shedding in these infections was accompanied by the temporary recovery of the snail reproductive regression due to s. mansoni infection. snail fe ... | 1990 | 2263415 |
| effects of schistosoma mansoni on the nutrition of its intermediate host, biomphalaria glabrata. | biomphalaria glabrata infected with schistosoma mansoni and maintained on an artificial diet of spirulina alga displayed reduced growth during the 5 wk following patency. food consumption per unit snail weight was unaffected. infected snails also failed to lay eggs. no difference in percentage of assimilation was observed between control and infected individuals, but infected snails had significantly decreased gross conversion efficiencies. the effects of infection on nutrition of b. glabrata we ... | 1989 | 2926600 |
| schistosoma mansoni modulation of phagocytosis in biomphalaria glabrata. | both short-term (3 hr) exposure of biomphalaria glabrata snails (m-line and 13-16-r1) to schistosoma mansoni (pr1) miracidia and in vitro incubation of parasite sporocysts with host hemolymph components altered host phagocytic ability. hemocytes obtained from susceptible (m-line) snails that had been exposed to parasite miracidia for 3 hr showed reduced levels of phagocytosis of yeast cells in vitro compared to hemocytes from unexposed individuals. incubation of whole hemolymph with sporocysts i ... | 1990 | 2299527 |
| schistosoma mansoni: comparison of a caribbean and african strain and experimental crossing based on compatibility with intermediate hosts and rattus rattus. | to elucidate changes relative to compatibility with intermediate and definitive hosts affecting schistosoma mansoni since it was introduced to the new world, the compatibility of s. mansoni from africa (the cameroons), from the caribbean (guadeloupe), and those resulting from experimental crosses with the gastropods biomphalaria glabrata and b. pfeifferi has been studied. results show that s. mansoni, regardless of its origin or its usual snail host, always infects b. pfeifferi more successfully ... | 1986 | 3082664 |
| a comparative study of the effects of phebrol on the respiratory chains of rat liver, biomphalaria glabrata and oncomelania nosophora. | 1. phebrol (sodium 2,5-dichloro-4-bromophenol), a synthetic molluscicide against oncomelania nosophora, showed a dual effect on rat liver submitochondria, acting as an uncoupler at low concentrations (approximately 10 microm) and an inhibitor of succinate-cytochrome c reductase at high concentrations. 2. phebrol also inhibited the enzymes responsible for succinate-fumarate conversion, i.e. the succinate-cytochrome c reductase, fumarate reductase and nadh-cytochrome c reductase of the mitochondri ... | 1991 | 1675968 |
| serological studies of the antigens prepared from biomphalaria glabrata snails infected and uninfected with schistosoma mansoni. i. indirect immunofluorescent antibody test using infected snail and adult worm antigens. | | 1987 | 3106521 |
| schistosoma mansoni and biomphalaria glabrata have some common epitopes. i. common epitopes are present on the surface of early stages of s. mansoni. | 1. the presence of snail and glycocalyx antigens in the schistosoma mansoni cercarial surface and their permanence throughout development in vitro and in vivo was investigated. 2. rabbit antisera raised against two fractions of glycocalyx released from cercariae and biomphalaria glabrata soft tissues or haemolymph were obtained. 3. all four antisera bound to cercariae and schistosomula kept in vitro or in vivo for up to 24 hr. 4. no binding to schistosomula kept in vivo for 5 days or longer was ... | 1991 | 1726079 |
| serological studies of the antigens prepared from biomphalaria glabrata snails infected and uninfected with schistosoma mansoni. ii. double diffusion technique using cercarial, adult worm, infected and uninfected snail antigens. | | 1987 | 3121764 |
| schistosoma mansoni: influence of biomphalaria glabrata size on susceptibility to infection and resultant cercarial production. | biomphalaria glabrata snails of the same age, but different sizes, were used to determine size-related susceptibility to schistosoma mansoni miracidial infection and the influence of snail size on total cercarial production. snails with shell diameters from less than 5 to greater than 17 mm were individually exposed to one or several miracidia, depending on the experiment. in snails exposed to multiple numbers of miracidia, the percentage of snails which developed patent infections was lower in ... | 1990 | 2311711 |
| [susceptibility of biomphalaria glabrata, b. straminea and b. tenagophila to various strains of schistosoma mansoni]. | | 1987 | 3130655 |
| schistosoma mansoni: characterization of clones maintained by the microsurgical transplantation of sporocysts. | five male and 5 female clones of schistosoma mansoni were established and maintained for 3 yr by the serial microsurgical transplantation of sporocysts from infected to uninfected biomphalaria glabrata snails. the clones were initially derived from 10 randomly selected snails with monomiracidial infections. clones were characterized by several criteria, including their infectivities for mice and snails, their cercarial outputs, and their ability to produce immunity in mice. the mean infectivitie ... | 1988 | 3142991 |
| differential binding of hemolymph proteins from schistosome-resistant and -susceptible biomphalaria glabrata to schistosoma mansoni sporocysts. | humoral factors have been associated with resistance of biomphalaria glabrata to infection by schistosoma mansoni. the goal of this study was to determine which serum (cell-free hemolymph) proteins bind to the surface of s. mansoni sporocysts. for this, 125i-labeled serum from schistosome-resistant (10-r2) and -susceptible (m-line) b. glabrata was incubated with sporocysts, washed, and then subjected to sds-page and autoradiography. other samples examined included radiolabeled 10-r2 and m-line s ... | 1990 | 2319423 |
| interactions between the plasma proteins of biomphalaria glabrata (gastropoda) and the sporocyst tegument of schistosoma mansoni (trematoda). | the tegumental surface of schistosoma mansoni sporocysts is the site of both nutritive and immunological interactions with haemolymph cells and plasma of biomphalaria glabrata, the schistosome intermediate host. within minutes of being placed in host plasma, sporocysts acquire plasma antigens, and within 3 h host plasma antigens are present on the surface at near steady state. though a wide variety of peptides is acquired, there is selection. furthermore, some differences occur in the peptides a ... | 1986 | 2426650 |
| [isolation of a human strain of schistosoma mansoni, sambon,1907]. | in this paper the authors briefly describe a human schistosoma mansoni strain from pará state, brazil. the cirene's strain was capable of infecting 71.4% of the snail vector biomphalaria glabrata (telegrafo's strain) provided by the "evando chagas" institute, belém. the cycle was completed by the infection of six mice. the thoracic and abdominal organs were examined microscopically which demonstrated the passage of the worm into the liver and lungs. the authors discuss the importance of these re ... | 1987 | 3151112 |
| schistosoma rodhaini: intramolluscan larval development, migration and replication processes of daughter sporocysts. | the larval development of schistosoma rodhaini in biomphalaria glabrata presents two features of interest. the first concerns the migration of daughter sporocysts: only a fraction of the daughter sporocysts produced by the mother sporocyst migrate directly towards the digestive gland of the snail and become cercariogenous; the others remain in the anterior region of the snail where the majority transforms into small sporocystogenous sporocysts. the second point concerns the replication processes ... | 1989 | 2566260 |
| the biochemical ecology of biomphalaria glabrata, a snail host of schistosoma mansoni: short chain carboxylic and amino acids as phagostimulants. | 1. a buccal mass olfactometer was used to investigate the responses of the fresh-water pulmonate snail biomphalaria glabrata to carboxylic and amino acids. 2. the snails proved very discriminating as only 6 (14.6%) of the 41 chemical species tested were effective as phagostimulants. these are ranked as follows in order of potency:- butanoate greater than propanoate greater than d-malate greater than 2-hydroxybutanoate = l-tartrate = l-aspartate. 3. the structure-activity relationships of the act ... | 1989 | 2570673 |
| strain variation in the infectivity of schistosoma mansoni for biomphalaria glabrata. | | 1988 | 3201064 |
| effect of infection with trichobilharzia ocellata and schistosoma mansoni on the ultrastructure of the albumen gland of their respective hosts, lymnaea stagnalis and biomphalaria glabrata. | the albumen gland, a female accessory sex gland of pulmonate snails, produces the perivitelline fluid. the ultrastructure of the albumen glands of control and infected specimens of lymnaea stagnalis and biomphalaria glabrata was studied. the albumen gland of l. stagnalis contains two types of secretory cells--light (active) and dark (inactive)--and two types of supporting cells--centroacinar and myoepithelial. the secretory cells apparently represent two activity stages of one type of cell. the ... | 1989 | 2606384 |
| linkage relationships of seven enzyme and two pigmentation loci in the snail biomphalaria glabrata. | crossing experiments with inbred stocks of the snail (biomphalaria glabrata) demonstrated that variants at two loci determining pigmentation and seven enzyme-determining loci exhibited normal mendelian segregation ratios in f2 progeny. among 39 pairwise comparisons for joint segregation, there was evidence of genetic linkage between a locus controlling mantle pigmentation (s) and 6-phosphogluconate dehydrogenase (pgd) and confirmation of a previously described linkage between esterase-2 (est-2) ... | 1988 | 3209852 |
| comparison of haemolymph proteins from schistosoma mansoni (trematoda)-susceptible and resistant biomphalaria glabrata (gastropoda). | 1. whole and haemoglobin (hb)-depleted serum fractions from schistosoma mansoni-resistant (10-r2) and schistosome-susceptible (pr albino, m-line) strains of biomphalaria glabrata were studied using sodium dodecyl sulphate-polyacrylamide gel electrophoresis, immunoblotting and protein assays. 2. whole serum of the pr albino strain had more total protein (11.4 +/- 1.9 mg protein/ml) than the 10-r2 strain (7.8 +/- 3.0 mg protein/ml). 3. there are specific differences in the polypeptide profiles of ... | 1988 | 3224503 |
| influence of experimental illumination and seasonal variation on crossbreeding mating in the snail biomphalaria glabrata. | the crossbreeding activities of the schistosoma mansoni vector snail biomphalaria glabrata were counted in a laboratory aquarium throughout the year under two regimes of 12h light: 12h dark from 7 a. m. to 10 p. m. mating increased significantly in autumn and winter and just missed a significant inverse correlation with temperature and a direct one with locomotion. other similar experiments were carried out to compare mating under various illumination conditions in complete daily cycle measureme ... | 1988 | 3249562 |
| ultrastructural evidence for the destruction of schistosoma mansoni sporocysts associated with elevated lysosomal enzyme levels in biomphalaria glabrata. | the activity levels of serum acid phosphtase, aminopeptidase, and lysozyme in a brazilian strain of biomphalaria glabrata were ascertained at 1, 2, and 3 hr after mechanical wounding or injection with albumin on the 30th day postexposure to a compatible strain of schistosoma mansoni miracidia and found to be elevated. parallel transmission electron microscope studies on daughter sporocysts and developing cercariae at these time intervals revealed progressive disintegration of the parasites that ... | 1989 | 2614603 |
| systemic infection of laboratory-reared biomphalaria glabrata (mollusca: gastropoda) with an acid-fast bacillus. | | 1988 | 3373006 |
| secretory protein biosynthesis in snail hemocytes: in vitro modulation by larval schistosome excretory-secretory products. | circulating hemocytes of the snail, biomphalaria glabrata, synthesize and secrete a variety of polypeptides when maintained in vitro in serum-free medium containing [35s] methionine. sds-page/fluorographic analysis of supernatants from resistant snail (10-r2-ok strain) hemocyte cultures revealed the presence of numerous labeled polypeptides ranging in mr from 220 to 14 kda. most of these same proteins were also produced by hemocytes of a susceptible b. glabrata strain (m-line), but the overall r ... | 1988 | 3397815 |
| experimental maintenance of the schistosome vector biomphalaria glabrata on an improved alginate gel. | an improved alginate formulation containing spirulina algae or freeze-dried lettuce is described for experimental maintenance of biomphalaria glabrata. snail growth, food consumption and assimilation were higher on the gel containing spirulina. the increased growth was not entirely the result of the higher food consumption observed with spirulina, but appeared to be due to nutritional differences between the two nutrient sources. snails responded to decreased dietary spirulina concentration by i ... | 1988 | 3401070 |
| structural analysis of hemolymph proteins from schistosoma mansoni (trematoda)-susceptible and resistant biomphalaria glabrata (gastropoda). | 1. five different molecular weight polypeptides from serum (cell-free hemolymph) of schistosoma mansoni-resistant and susceptible strains of biomphalaria glabrata, were examined by two-dimensional 125i-peptide mapping and high performance liquid chromatography (hplc). 2. peptide mapping indicated that all five radiolabeled polypeptides within and between the two snail strains had similar migration patterns when cleaved with pepsin or alpha-chymotrypsin, thus revealing a shared structural homolog ... | 1989 | 2620499 |
| phagocytosis of yeast by biomphalaria glabrata: carbohydrate specificity of hemocyte receptors and a plasma opsonin. | in vitro phagocytosis of yeast cells by hemocytes of the mollusc biomphalaria glabrata can occur in the absence of plasma, but is enhanced by opsonization in plasma from certain snail strains. we have investigated the carbohydrate specificity of the hemocyte-bound receptor for phagocytosis and the free plasma opsonin using two dominant carbohydrate components of the yeast cell wall (laminarin and mannan). phagocytic uptake in the absence of plasma of both untreated and opsonized yeast is strongl ... | 1989 | 2670623 |