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Weise K, Kurth T, Politowski I, Winkelmann C, Schäffer A, Kretschmar S, Berendonk TU, Jungmann D. A workflow to investigate the impacts of weathered multi-walled carbon nanotubes to the mud snail Lymnaea stagnalis. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:26706-26725. [PMID: 34859348 PMCID: PMC8989799 DOI: 10.1007/s11356-021-17691-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 11/18/2021] [Indexed: 06/13/2023]
Abstract
Although the development and application of nanomaterials is a growing industry, little data is available on the ecotoxicological effects on aquatic organisms. Therefore, we set up a workflow to address the potential uptake of weathered multi-walled carbon nanotubes (wMWCNTs) by a model organism, the pulmonary mud snail Lymnaea stagnalis (L. stagnalis), which plays an important role in the food web. It represents a suitable organism for this approach because as a grazer it potentially ingests large amounts of sedimented wMWCNTs. As food source for L. stagnalis, benthic biofilm was investigated by the use of a transmission electron microscope (TEM) and a scanning electron microscope (SEM) after exposure with wMWCNTs. In addition, isotopic labeling was applied with 14C-wMWCNTs (0.1 mg/L) to quantify fate, behavior, and enrichment of 14C-wMWCNTs in benthic biofilm and in L. stagnalis. Enrichment in benthic biofilm amounted to 529.0 µg wMWCNTs/g dry weight and in L. stagnalis to 79.6 µg wMWCNTs/g dry weight. A bioconcentration factor (BCF) for L. stagnalis was calculated (3500 L/kg). We demonstrate the accumulation of wMWCNTs (10 mg/L) in the digestive tract of L. stagnalis in an effect study. Moreover, the physiological markers glycogen and triglycerides as indicators for the physiological state, as well as the RNA/DNA ratio as growth indicator, were examined. No significant differences between exposed and control animals were analyzed for glycogen and triglycerides after 24 days of exposure, but a decreasing trend is recognizable for triglycerides. In contrast, the significant reduction in the RNA/DNA ratio of L. stagnalis indicated an inhibition of growth with a following recovery after depuration. The described workflow enables a comprehensive determination of the fate and the behavior of wMWCNTs specifically and in general all kinds of CNTs in the aquatic environment and therefore contributes to a holistic risk assessment of wMWCNTs.
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Affiliation(s)
- Katrin Weise
- Institute for Hydrobiology, Faculty of Environmental Sciences, Technische Universität Dresden, Zellescher Weg 40, 01217, Dresden, Germany.
| | - Thomas Kurth
- Technology Platform, Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Fetscherstraße 105, 01307, Dresden, Germany
| | - Irina Politowski
- Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Carola Winkelmann
- Institute for Integrated Natural Sciences, University of Koblenz-Landau, Universitätsstraße 1, 56070, Koblenz, Germany
| | - Andreas Schäffer
- Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Susanne Kretschmar
- Technology Platform, Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Fetscherstraße 105, 01307, Dresden, Germany
| | - Thomas Ulrich Berendonk
- Institute for Hydrobiology, Faculty of Environmental Sciences, Technische Universität Dresden, Zellescher Weg 40, 01217, Dresden, Germany
| | - Dirk Jungmann
- Institute for Hydrobiology, Faculty of Environmental Sciences, Technische Universität Dresden, Zellescher Weg 40, 01217, Dresden, Germany
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Functional Histology and Ultrastructure of the Digestive Tract in Two Species of Chitons (Mollusca, Polyplacophora). JOURNAL OF MARINE SCIENCE AND ENGINEERING 2022. [DOI: 10.3390/jmse10020160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
To continue the investigation on the digestive system of polyplacophoran molluscs, a histological and ultrastructural study of the oesophagus, stomach and intestine of Chaetopleura angulata and Acanthochitona fascicularis was carried out. Stomach content examination revealed an omnivorous diet. In both species the epithelium of the whole digestive tract consisted mostly of elongated absorptive cells with an apical border of microvilli. Cilia were also frequently present. Mitochondria and electron-dense lysosomes were the prominent organelles in the region above the nucleus. The basal region was characterised by an association of mitochondria, peroxisomes and lipid droplets. In general, glycogen deposits were also abundant in absorptive cells. The ultrastructural features indicate that the absorptive cells of the digestive tract epithelium are involved in endocytosis, intracellular digestion and storage of reserves. Histochemical techniques showed that the secretory cells of the digestive tract contained proteins and polysaccharides in their secretory vesicles. The secretory cells with vesicles of low electron density were classified as mucous cells, and the ones with electron-dense vesicles were designated basophilic cells due to their staining by basic dyes in light microscopy. Additionally, basal cells that seem to correspond to enteroendocrine cells containing oval electron-dense vesicles were found along the digestive tract epithelium of both species. The thin outer layer of the digestive tract wall consisted of muscle cells and nerves embedded in connective tissue.
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Structure and function of the digestive system in molluscs. Cell Tissue Res 2019; 377:475-503. [DOI: 10.1007/s00441-019-03085-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 07/26/2019] [Indexed: 02/06/2023]
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Lobo-da-Cunha A, Pereira-Sousa J, Oliveira E, Alves Â, Guimarães F, Calado G. Calcium Detection and Other Cellular Studies in the Esophagus and Crop of the Marine SlugAglaja tricolorata(Euopisthobranchia, Cephalaspidea). MALACOLOGIA 2014. [DOI: 10.4002/040.057.0209] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Croteau MN, Cain DJ, Fuller CC. Novel and nontraditional use of stable isotope tracers to study metal bioavailability from natural particles. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:3424-3431. [PMID: 23458345 DOI: 10.1021/es400162f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We devised a novel tracing approach that involves enriching test organisms with a stable metal isotope of low natural abundance prior to characterizing metal bioavailability from natural inorganic particles. In addition to circumventing uncertainties associated with labeling natural particles and distinguishing background metals, the proposed "reverse labeling" technique overcomes many drawbacks inherent to using radioisotope tracers. Specifically, we chronically exposed freshwater snails ( Lymnaea stagnalis ) to synthetic water spiked with Cu that was 99.4% (65)Cu to increase the relative abundance of (65)Cu in the snail's tissues from ~32% to >80%. The isotopically enriched snails were then exposed to benthic algae mixed with Cu-bearing Fe-Al particles collected from the Animas River (Colorado), an acid mine drainage impacted river. We used (63)Cu to trace Cu uptake from the natural particles and inferred their bioavailability from calculation of Cu assimilation into tissues. Cu assimilation from these particles was 44%, indicating that 44% of the particulate Cu was absorbed by the invertebrate. This demonstrates that inorganic particulate Cu can be bioavailable. The reverse labeling approach shows great potential in various scientific areas such as environmental contamination and nutrition for addressing questions involving uptake of an element that naturally has multiple isotopes.
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Affiliation(s)
- Marie-Noële Croteau
- US Geological Survey, MS 496, 345 Middlefield Road, Menlo Park, California 94025, United States.
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Martinez-Pereira MA, Franceschi RDC, Antunes GDF, Coelho BP, Achaval M, Zancan DM. General Morphology and Innervation of the Midgut and Hindgut ofMegalobulimus abbreviatus(Gastropoda, Pulmonata). Zoolog Sci 2013; 30:319-30. [DOI: 10.2108/zsj.30.319] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Cain DJ, Croteau MN, Fuller CC. Dietary bioavailability of Cu adsorbed to colloidal hydrous ferric oxide. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:2869-2876. [PMID: 23402601 DOI: 10.1021/es3044856] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The dietary bioavailability of copper (Cu) adsorbed to synthetic colloidal hydrous ferric oxide (HFO) was evaluated from the assimilation of (65)Cu by two benthic grazers, a gastropod and a larval mayfly. HFO was synthesized, labeled with (65)Cu to achieve a Cu/Fe ratio comparable to that determined in naturally formed HFO, and then aged. The labeled colloids were mixed with a food source (the diatom Nitzschia palea) to yield dietary (65)Cu concentrations ranging from 211 to 2204 nmol/g (dry weight). Animals were pulse fed the contaminated diet and assimilation of (65)Cu from HFO was determined following 1-3 days of depuration. Mass transfer of (65)Cu from HFO to the diatom was less than 1%, indicating that HFO was the source of (65)Cu to the grazers. Estimates of assimilation efficiency indicated that the majority of Cu ingested as HFO was assimilated (values >70%), implying that colloidal HFO potentially represents a source of dietary Cu to benthic grazers, especially where there is active formation and infiltration of these particles into benthic substrates.
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Affiliation(s)
- Daniel J Cain
- U.S. Geological Survey, Menlo Park, California, USA.
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Lobo-da-Cunha A, Oliveira E, Ferreira I, Coelho R, Calado G. Histochemical and ultrastructural characterization of the posterior esophagus of Bulla striata (Mollusca, Opisthobranchia). MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2010; 16:688-698. [PMID: 20883598 DOI: 10.1017/s1431927610093840] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The posterior esophagus of Bulla striata, running from the gizzard to the stomach, was investigated with light and electron microscopy to obtain new data for a comparative analysis of the digestive system in cephalaspidean opisthobranchs. In this species, the posterior esophagus can be divided into two regions. In the first, the epithelium is formed by columnar cells with apical microvilli embedded in a cuticle. Many epithelial and subepithelial secretory cells are present in this region. In both, electron-lucent secretory vesicles containing filaments and a peripheral round mass of secretory material fill the cytoplasm. These acid mucus-secreting cells may also contain a few dense secretory vesicles. In the second part of the posterior esophagus, the cuticle is absent and the epithelium is ciliated. In this region, epithelial cells may contain larger lipid droplets and glycogen reserves. Subepithelial secretory cells are not present, and in epithelial secretory cells the number of dense vesicles increases, but most secretory cells still contain some electron-lucent vesicles. These cells secrete a mixture of proteins and acid polysaccharides and should be considered seromucous. The secretory cells of the posterior esophagus are significantly different from those previously reported in the anterior esophagus of this herbivorous species.
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Affiliation(s)
- Alexandre Lobo-da-Cunha
- Laboratory of Cell Biology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, 4099-003 Porto, Portugal.
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Lobo-da-Cunha A, Oliveira E, Alves Â, Coelho R, Calado G. Light and electron microscopic study of the anterior oesophagus ofBulla striata(Mollusca, Opisthobranchia). ACTA ZOOL-STOCKHOLM 2010. [DOI: 10.1111/j.1463-6395.2009.00392.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Zaitseva OV, Kuznetsova TV, Markosova TG. NADPH-diaphorase activity in the digestive system of gastropod molluscs Achatina fulica and Littorina littorea. J EVOL BIOCHEM PHYS+ 2009. [DOI: 10.1134/s002209300901013x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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11
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Lobo-da-Cunha A, Batista-Pinto C. Ultrastructural, histochemical and cytochemical characterization of intestinal epithelial cells in Aplysia depilans (Gastropoda, Opisthobranchia). ACTA ZOOL-STOCKHOLM 2007. [DOI: 10.1111/j.1463-6395.2007.00268.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Zurawell RW, Goldberg JI, Holmes CFB, Prepas EE. Tissue distribution and oral dose effects of microcystin in the freshwater pulmonate snail Lymnaea stagnalis jugularis (Say). JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2007; 70:620-6. [PMID: 17365616 DOI: 10.1080/15287390600974510] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Microcystin (MC) concentrations were measured in the alimentary tract, digestive gland, and remaining visceral mass of adult pulmonate snails (Lymnaea stagnalis) exposed to cyanobacteria known to contain MC. The highest proportion of total body MC content was measured within the alimentary tract (83%), though an appreciable proportion (17%) was also found within the digestive gland tissue. This provides conclusive evidence for the limited digestion of toxic cyanobacteria and subsequent uptake and accumulation of MC by the digestive gland of L. stagnalis. Additionally, pure microcystin-LR was orally administered to adult L. stagnalis to investigate the potential for toxic effects. Exposure to microcystin-LR induced histopathological alterations of the digestive glands consistent with those reported elsewhere for mammals and fish, indicating a common mode of toxicity to both vertebrates and invertebrates.
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Affiliation(s)
- Ronald W Zurawell
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
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Zurawell RW, Holmes CFB, Prepas EE. Elimination of the cyanobacterial hepatotoxin microcystin from the freshwater pulmonate snail Lymnaea stagnalis jugularis (say). JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2006; 69:303-18. [PMID: 16407089 DOI: 10.1080/15287390500227498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
It has been suggested that little to no microcystin (MC), a cyanobacterial hepatotoxin, accumulates within freshwater pulmonate snails because the toxin is associated primarily with undigested gut contents that are eliminated from the animal via egestion. To test this, Lymnaea stagnalis exposed to MC-containing cyanobacteria were placed into toxin-free environments and sampled over short (24 h at 21 degrees C) and long (30 d at 22 and 10 degrees C) time periods. Within 8 h after being removed from exposure to microcystin-containing phytoplankton, the gizzard and cecal string fractions of the feces were eliminated, accounting for 57% of the initial MC concentration. However, detectable concentrations remained beyond 24 h, likely in association with the digestive-gland contents, which can be retained up to 100 h. Long-term MC loss was biphasic at two ambient temperatures. The greatest change (fast phase) occurred over the first 3 d after exposure. By 6 d, the cumulative MC loss from L. stagnalis was 80 and 95% at 10 and 22 degrees C, respectively. Toxin loss over this period was attributed to egestion of indigestible cells/colonies from gizzard and cecum, as well as elimination of unassimilated MC-laden fragments and vacuolate excretion of residues from the digestive gland. The fast-phase depuration rate constant was significantly higher at 22 than at 10 degrees C, indicating an influence of ambient temperature on the rate of toxin loss from pulmonate snails. Depuration continued at slower rates until 30 d, when most (97.5 and 99.5% at 10 and 22 degrees C, respectively) of the initial MC was eliminated.
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Affiliation(s)
- Ronald W Zurawell
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta.
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Lobo-da-Cunha A, Batista-Pinto C. Light and electron microscopy studies of the oesophagus and crop epithelium in Aplysia depilans (Mollusca, Opisthobranchia). Tissue Cell 2005; 37:447-56. [PMID: 16260017 DOI: 10.1016/j.tice.2005.06.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2004] [Revised: 06/07/2005] [Accepted: 06/13/2005] [Indexed: 11/26/2022]
Abstract
The oesophagus and crop epithelium of Aplysia depilans consist in a single layer of columnar cells with apical microvilli, and some of them also possess cilia. Cell membrane invaginations, small vesicles, multivesicular bodies and many dense lysosomes were observed in the apical region of the cytoplasm. In most cells, a very large lipid droplet was observed above the nucleus and a smaller one was frequently found below the nucleus; glycogen granules are also present. Considering these ultrastructural features, it seems that these cells collect nutritive substances from the lumen by endocytosis, digest them in the apical lysosomes and store the resulting products. The cell bodies of mucus secreting flask-shaped cells are subepithelial in the oesophagus and intraepithelial in the crop. Histochemistry methods showed that the secretion stored in these cells contains acidic polysaccharides. Secretory vesicles with thin electron-dense filaments scattered in an electron-lucent background fill most of these cells, and the basal nucleus is surrounded by dilated rough endoplasmic reticulum cisternae containing small tubular structures. Considering the relatively low number of secretory cells, mucus production cannot be high. Moreover, since protein secreting cells were not observed in either oesophagus or crop, extracellular digestion in the lumen of these anterior segments of the digestive tract most probably depend on the enzymes secreted by the salivary and digestive glands.
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Affiliation(s)
- Alexandre Lobo-da-Cunha
- Laboratory of Cell Biology, Abel Salazar Institute of Biomedical Sciences, ICBAS, University of Porto, Largo Abel Salazar 2, 4099-003 Porto, Portugal.
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Ballance S, Howard M, White KN, McCrohan CR, Thornton DJ, Sheehan JK. Partial characterisation of high-molecular weight glycoconjugates in the trail mucus of the freshwater pond snail Lymnaea stagnalis. Comp Biochem Physiol B Biochem Mol Biol 2004; 137:475-86. [PMID: 15081999 DOI: 10.1016/j.cbpc.2004.02.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2003] [Revised: 01/04/2004] [Accepted: 02/06/2004] [Indexed: 11/26/2022]
Abstract
We have studied the glycoconjugates in trail mucus of the pond snail Lymnaea stagnalis. The mucus was dissolved with 6 M guanidinium hydrochloride (GuHCl) and the major component was comprised of very high-M(r) glycoconjugates that were eluted in the void volume of a Sepharose CL-4B gel-filtration column. This high-M(r) material was pooled and thereafter subjected to density gradient centrifugation first in 4 M GuHCl/CsCl and subsequently 0.2 M GuHCl/CsCl to further remove non-glycosylated proteins and DNA. The harvested glycoconjugate pool chromatographed in the void volume of Sepharose CL-2B. However, reduction of disulfide bonds lowered the molecular size of approximately 80% of the void material yielding a major fragment and some minor smaller fragments in gel chromatography. The reduced glycoconjugates were digested with papain and yielded high molecular weight, proteinase-resistant glycopeptides. This fragmentation pattern is similar to that found for oligomeric gel-forming mucins in mammals and the amino acid composition (60% Ser/Thr) and sugar analysis of the glycopeptides is consistent with mucin-like molecules, there being no significant amounts of xylose or uronic acids. The residual 20% of the preparation, which apparently resisted reduction and protease digestion, had a similar amino acid composition to the bulk, but was somewhat different in sugar composition, containing some xylose and a significant amount of glucuronic acid. The two groups of molecules had very different morphologies in the electron microscope. Taken together, these data suggest that trail mucus is a complex mixture of at least two families of protein-glycoconjugate molecules based upon the gel-forming mucin and proteoglycan families, though we cannot rule out that polysaccharides may also be present.
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Affiliation(s)
- Simon Ballance
- School of Biological Sciences, University of Manchester, Manchester M13 9PL, UK.
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Lobo-da-Cunha A, Batista-Pinto C. Stomach of Aplysia depilans (Mollusca, Opisthobranchia): a histochemical, ultrastructural, and cytochemical study. J Morphol 2003; 256:360-70. [PMID: 12655617 DOI: 10.1002/jmor.10099] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We report the results of a morphological, histochemical, and cytochemical characterization of the Aplysia depilans stomach, an organ little studied in opisthobranchs. Very thin ciliated cells with microvilli on their apical surfaces are predominant in the epithelium lining the lumen of the stomach. Many lysosomes with a strong arylsulphatase activity were present in the apical regions of these cells that could also contain some lipid droplets and glycogen. Small peroxisomes were observed, usually around lipid droplets or mitochondria. Bottle-shaped secretory cells are very common in this epithelium and produce a secretion rich in proteins and acidic mucopolysaccharides. Most of the cytoplasm of these mucus-producing cells was filled with a very high number of granules and the nucleus is dislocated to the basal region. Cisternae of rough endoplasmic reticulum were abundant around the nucleus and several Golgi stacks were also present in this area. In spite of the variation in the electron density of the granules, only one type of secretory cell seems to be present in the stomach epithelium, since granules with very different electron densities were frequently found in the same cell. A few neurons were also found in the stomach epithelium of this species. Fibrocytes, muscle cells, nerves, and amebocytes were observed in the connective tissue of the stomach wall.
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Affiliation(s)
- Alexandre Lobo-da-Cunha
- Laboratory of Cell Biology, ICBAS, Institute of Biomedical Sciences Abel Salazar, Oporto University, Portugal.
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Franchini A, Ottaviani E. Intestinal cell types in the freshwater snail planorbarius corneus: Histochemical, immunocytochemical and ultrastructural observations. Tissue Cell 1992; 24:387-96. [DOI: 10.1016/0040-8166(92)90055-c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/1991] [Revised: 02/14/1992] [Indexed: 10/27/2022]
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Marchand CR, Colard C. Presence of cells and fibers immunoreactive toward antibodies to different peptides or amine in the digestive tract of the snailHelix aspersa. J Morphol 1991; 207:185-190. [DOI: 10.1002/jmor.1052070209] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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