Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An attempt was made to characterize the hemolymph of Biomphalaria glabrata with reference to "normal" intra-specific variation, i.e., both inter- and intra-strain differences. Total protein concentration, per cent hemoglobin, pH, and osmolarity were studied. Seven geographic strains of B, glabrata were examined. In addition, observations were made on the hemolymph of Biomphalaria straminea, several strains of Helisoma caribaeum, and on B. glabrata subjected to infection with Schistosoma mansoni or to periods of starvation. Intra-strain differences in total protein concentration and total hemoglobin concentration in B. glabrata appeared to be more closely related with snail size than with absolute age. Inter-strain variation in B. glabrata was also noted, but the differences were of the same magnitude as those from intra-strain samples. Significant differences in total protein concentration were observed, however, between the means of similar size B. glabrata, B. straminea and H. caribaeum. The osmolatity of the hemolymph from different size B. glabrata was similar as were the osmolalities of the hemolymph from similar size snails of different strains. However, all B. glabrata strains exhibited hemolymph osmolalities lower than observed in strains of H. caribaeum. Infection with S. mansoni reduced the protein concentration of B. glabrata hemolymph. Differences were noted as early as 1.5-24 hr post-infection, with significant alterations occurring at about 11 days post-infection. To a lesser extent, starvation also depleted the protein content of the hemolymph.
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PMID:Intraspecific variations in the hemolymph of Biomphalaria glabrata, a snail host of Schistosoma mansoni. 0 98

The metabolism of the snail Biomphalaria glabrata stressed by five days' starvation as well as by infection with Schistosoma mansoni was examined with regard to the metabolism of ketone bodies. Previous studies in the metabolism of this host--parasite relationship always resulted in changes in the same direction with starvation as well as with infection. Contrary to that the concentration of acetoacetate and beta-hydroxybutyrate measured in the hemolymph decreased significantly with starvation but increased significantly with infection. The following problems concerning the ketone body metabolism are discussed: on the one hand the differences between infected and starved snails, and on the other hand the differences between the snails and the mammals as well as in the invertebrates so far investigated.
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PMID:[The ketone bodies in the hemolymph of Biomphalaria glabrata under starvation and infection with Schistosoma mansoni (author's transl)]. 91 81

The gastrodermis of adult Schistosoma mansoni was examined by electron microscopy to determine the effects of starvation and the effects of hycanthone, administered in vitro. Special attention was focused on the relationship of the Golgi complexes with the process of autophagy. In general, autophagy was increased in the gastrodermis when it was exposed to stress conditions such as starvation and hycanthone. Acid phosphatase and thiamine pyrophosphatase activities were used as enzyme markers for the Golgi complexes and lysosomes. During the early stages of starvation, there was a 4-fold increase in the number of Golgi complexes per unit area in the gastrodermis. A progressive increase in the number of secondary lysosomes was evident as starvation time was increased. Hycanthone accelerated the effects of starvation. It was hypothesized that acid hydrolases are passed to the Golgi complexes via ER-derived vesicles. The enzymes are subsequently released as primary lysosomes from the Golgi complex to fuse with cytosegresomes and form secondary lysosomes (cytosomes).
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PMID:Cytochemistry of gastrodermal autophagy following starvation in Schistosoma mansoni. 112 52

Female Schistosoma mansoni from unisexual infections have scant pharyngeal musculature, thin intestinal cecal walls, pale and scanty intestinal contents, and lack acidic thiol proteinase digestive enzyme as determined by indirect immunofluorescence using a monoclonal antibody. Their intake of host erythrocytes, measured by 51Cr labeling, is about one-fourth that of paired adult females, and they appear to be starved. In contrast, paired adult females have heavier pharyngeal musculature and intestinal cecal walls and abundant digestive enzyme in the anterior third of their intestinal tract. Females in worm pairs surgically transplanted into uninfected mice continued to feed, but separated females were carried into the liver and deteriorated. Adult female S. mansoni, newly separated from their male partners and incubated in vitro with labeled erythrocytes, ingested marginally fewer cells than did still-paired females, indicating their ability to continue feeding almost normally at least for a period after separation. Paired and ex-paired adult females declined similarly in feeding rate with increased time in vitro. In Schistosomatium douthitti, females grow and mature without males, the pharyngeal musculature and cecal walls are well developed, the gut is full of ingested blood, and the acidic thiol proteinase is present in both unisexual and paired female worms. There are different stimulatory pathways for growth and for reproductive maturation in S. mansoni, although both processes require physical contact with the male. We believe that the growth-stimulating function results from the muscular action of the clasping male, which helps the immature female to pump blood into her intestine, thereby overcoming a state of relative starvation.
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PMID:The role of Schistosoma mansoni males in feeding and development of female worms. 329 99

The 31P nuclear magnetic resonance (NMR) spectrum of the digestive gland-gonad complex (DGG) of the schistosome vector Biomphalaria glabrata was characterized and the effects of infection by Schistosoma mansoni noted. The in vivo spectrum was comprised of 11 peaks, 5 downfield and 6 upfield of an external 85% phosphoric acid standard. Based on a variety of analytical procedures, the upfield peaks from the standard were demonstrated to be composed of carbamoyl phosphate + a mixture of 3 phosphatides and sphingomyelin, the gamma + beta phosphorus resonances of nucleotide triphosphate (NTP) and nucleotide diphosphate (NDP), respectively, the alpha phosphorus resonances of NTP + NDP, NAD(H) + the phosphorus resonance of uridine phosphate from uridine diphosphoglucose (UDPG), the phosphorus resonance of glucose phosphate from UDPG and, last, the beta phosphorus resonance of NTP. The downfield peaks were assigned as glycerophosphoryl choline, intracellular inorganic phosphate (Pi), sugar phosphates + phosphoryl choline, aminoethyl phosphonate (AEP), and ceramide AEP. T1 values for the in vivo NMR components were determined by inversion recovery. Infection produced distinct alterations in the levels of nonnucleotide components of the in vivo 31P NMR spectrum and the spectra of tissue extracts. Specifically, the levels of phosphonate, phospholipids, and carbamoyl phosphate were markedly reduced, and the relative level of Pi was increased. The potential significance of these changes to the parasite-host relationship was discussed. In contrast, starvation resulted in a decreased level of phosphonate only. The pH of the intact DGG was estimated by titrating the inorganic phosphate component of tissue extracts. The mean pH was 6.9 for both control and infected material.
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PMID:Characterization of the 31P NMR spectrum of the schistosome vector Biomphalaria glabrata and of the changes following infection by Schistosoma mansoni. 357 67

1. The total lipid level of the digestive gland-gonad complex of Biomphalaria glabrata was reduced by starvation and elevated following infection with Schistosoma mansoni. 2. The lipid classes of B. glabrata were phospholipid, monoglyceride, free fatty acid, triglyceride, sterol ester and wax and a single unidentified lipid. The major lipid present in control, starved and infected tissue was sterol. Triglyceride was a minor component of control tissue. 3. Starvation reduced the relative level of the unidentified lipid but had little effect on triglyceride. 4. Infection also caused a decrease in the unidentified component but the triglyceride level was sharply elevated. 5. The phospholipid fraction of tissue from all groups was composed of phosphatidyl choline, phosphatidyl ethanolamine and phosphatidyl serine. Infection and starvation had little effect on the composition.
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PMID:Effect of Schistosoma mansoni on the gross lipid composition of its vector Biomphalaria glabrata. 362 3

Larval Schistosoma mansoni have been shown to induce morphological changes to the internal calcium reserves (in particular the calcareous inclusions in Type A calcium cells and to the inner, nacreous layer of the shell) of Biomphalaria glabrata within 48 h of miracidial penetration. Control experiments have shown that these changes were not due to either the experimental procedures used, mechanical damage or to starvation effects. The effects were, however, analogous to experimentally induced acidosis, suggesting that the rapidly transforming miracidium-sporocyst quickly induces changes in the host's metabolism, presumably by the production and release of CO2 and waste metabolites into the haemolymph.
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PMID:Biomphalaria glabrata: changes in calcium reserves following parasitism by larval Schistosoma mansoni. 369 64

The in vitro effects of suramin and trypan blue on schistosomules of Schistosoma mansoni were examined by light and electron microscopy. The drugs were administered to 12-day cultures of schistosomules produced by the penetration method. The larvae were maintained on mouse red blood cells for 5 days prior to addition of the drugs. At the concentrations used, the morphological changes attributable to the drugs were identical for the two drugs. The first signs of anomaly were observable at 8 hr after exposure. At this time, the digestive system showed signs reminiscent of early starvation effects such as alterations of the Golgi and an increase of autophagy. After 36 hr, a rapid disintegration of the gastrodermis became evident. It was hypothesized that the drugs initially inhibit the digestive enzymes and, subsequently, labilize the luminal plasma membrane of the gastrodermis. By 48 hr after exposure, the larvae were dead.
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PMID:Schistosoma mansoni: suramin and trypan blue in vitro and the ultrastructure of feeding schistosomules. 402 46

The oxygen consumption rate (VO(2)) of Biomphalaria glabrata populations, using polarometric and manometric methods, when plotted against dried body mass as logarithmic co-ordinates, respectively, fell on a regression line with a slope between 0.933 and 1.02. The slope of the regression line for non-infected Schistosoma mansoni populations was found to be 1.04 with no differences in the VO(2) between infected and non-infected snails. The VO(2) of CO-treated snails was the same as for the control snails. The VO(2) of starved snails declined after 3 days and was half the original value after 10 days starvation at 27 degrees C. The P(50) value for snail haemolymph containing haemoglobin suspended in a Tris-HCl buffer was 5.57(+/-0.73)mmHg at a pH of 7.51 and 25 degrees C. For Sephadex-75 cleaned haemolymph the P(50) value was 1.72(+/-0.07)mmHg at 25 degrees C and pH 7.51. Snails exposed to oxygen fs and to choices of different oxygen concentrations in water did not exclusively prefer high (130mmHg), low (15mmHg), or normal (80mmHg) oxygen tensions. The oxygen consumption rate of 782 cercariae at 27 degrees C was measured as 0.0092 microl O(2)/h per single cercaria. The results, when compared with the data in the literature [Z. Vergl. Physiol. 46 (1963) 467;; S. A. J. Zool. 14 (1979) 202], indicate that the mantle cavity gas bubble plays an insignificant or no role at all when pulmonate snails are kept in water with high partial pressures of oxygen and at low temperatures.
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PMID:The respiratory properties of Biomphalaria glabrata exposed to Schistosoma mansoni infection, starvation, CO, and choices of different oxygen concentrations. 1288 May 85

The cercariae of Schistosoma mansoni become transformed into schistosomula during host skin penetration. We have found that large acidophilic compartments are detected in schistosomula but not in cercariae or in any other stages of the parasite by use of the fluorescent dye LysoTracker, a dye specific for mammalian lysosomes. Some of these large acidic compartments incorporated monodansylcadaverine, a specific dye for autophagosomes. We have used potent inhibitors (wortmannin and 3-methyladenine) and a potent inducer (starvation) of autophagy to show that the pathway to the formation of the acidic compartments requires specific molecular signals from the environment and from the genome. Certain doses of ultraviolet light inhibited significantly the formation of the acidic compartments, which may indicate disruption of the lysosome/autophagosome pathway. We have also defined two proteins that are commonly associated with lysosomes and autophagosomes in mammalian cells, the microtubule-associated membrane protein (MAP-LC3) and lysosome-associated membrane protein (LAMP-1), in extracts of schistosomula. We suggest that the autophagy pathway could be developed in transformed schistosomula.
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PMID:The role of acidic organelles in the development of schistosomula of Schistosoma mansoni and their response to signalling molecules. 1579 14


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