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1.
The distribution of millipedes along an altitudinal gradient in the south of Lake Teletskoye, Altai, Russia based on new samples from the Kyga Profile sites, as well as on partly published and freshly revised material (Mikhaljova et al. 2007, 2008, 2014, Nefedieva and Nefediev 2008, Nefediev and Nefedieva 2013, Nefedieva et al. 2014), is established. The millipede diversity is estimated to be at least 15 species and subspecies from 10 genera, 6 families and three orders. The bulk of species diversity is confined both to low- and mid-mountain chern taiga forests and high-mountain shrub tundras, whereas the highest numbers, reaching up to 130 ind./m², is shown in subalpine Pinus sibirica sparse growths. Based on clustering studied localities on species diversity similarity two groups of sites are defined: low-mountain sites and subalpine sparse growths of Pinus sibirica ones.  相似文献   

2.
As a molecular carrier and storage protein, apolipoprotein (Apo) mediates the intracellular uptake of lipids, proteins, vitamins and carotenoids. In this study, we identified a novel Apo gene, designated hcApo, from the freshwater pearl mussel Hyriopsis cumingii. The complete hcApo cDNA consists of 4104 nucleotides with an open reading frame encoding 1155 amino acid residues. The hcApo protein contains a conserved lipoprotein N-terminal domain (LPD-N) that is a characteristic of the large lipid transfer protein (LLTP) superfamily. The hcApo mRNA is constitutively expressed in a wide range of tissues with the highest expression level in the liver. Moreover, differential expression analysis revealed that the hcApo gene is more highly expressed in the liver, kidney, mantle and gill of purple line mussels compared to white line mussels. In situ hybridization investigations of the precise expression site of hcApo mRNA in the mantle showed that hcApo mRNA is specifically expressed in the outer epithelial cells of the middle fold and the inner epithelial cells of the outer fold of the mantle, as well as throughout the outer epithelium of the outer fold and ventral mantle. Another very important finding is that significantly positive correlation existed between the hcApo gene expression level and the total carotenoid content in purple line mussels. These findings may provide a better understanding of the roles of hcApo in the molecular mechanisms of shell formation and coloring of H. cumingii.  相似文献   

3.
Zuojinwan (ZJW), a famous Chinese medicinal formula, contains two medicinal herbs Coptis chinese Frach and Evodia rutaecarpa (Juss.) Benth in the ratio of 6: 1. The inhibitory effects of ZJW on eight kinds of human cancer cell lines including SMMC-7721, BEL-7402, BEL-7404, HepG2, A549, NCI-H446, NCI-H460 and HCT- 116 cells were evaluated, and the possible mechanism was investigated. The growths of the eight kinds of cancer cells were inhibited by ZJW assessed through MTT assay. Flow cytometry assay revealed a sub-G1 peak with reduced DNA content was formed. The cell cycle was arrested in the G0/G1 phase in ZJW-treated SMMC-7721 and HepG2 cells, and in the S phase for NCI-H460 cells. Significant DNA damage was produced by ZJW assessed with single-cell gel electrophoresis assay. Morphological changes were also observed. Caspase-3 and -9 activities were increased following ZJW treatment. Western blot analysis showed that Bax and Bak protein levels were increased after ZJW treatment, while Bcl-2 and Bcl-xl protein levels were decreased. Our results suggest that ZJW has significant anti-cancer activities due to induction of mitochondria- dependent apoptosis pathway. Therefore, ZJW has the potential to be a novel chemotherapy drug to treat hepatoma, lung cancer and colon cancer by suppressing tumor growth.  相似文献   

4.
Two inner growths in the mantle beneath the epithelium were found in 1 of 1000 mussels Modiolus difficilis from Amursky Bay, Sea of Japan, within the city precincts of Vladivostok. Both growths were about 2000 microns in maximal diameter in section and elevated slightly above the mantle surface. The mantle epithelium near the growths formed deep invaginations, and clusters of mucous cells were numerous beneath the epithelium. Histological and histochemical methods were employed. Two different kinds of growth were revealed. The off-white growth consisted of cells with thin granular or vesicular cytoplasm containing glucosaminoglycans, proteins and a small amount of neutral polysaccharides. Growth cells were pure white in color after treatment of preparations with 1% H2SO4 and differed markedly from the mantle cells. The yellow growth consisted of large granular cells with neutral polysaccharides and proteins. Although growths were composed of different kinds of cells, they seemed to be derived from subepithelial mucous cells. This was supported by histological and histochemical staining reactions of some tumor and mantle epithelial cells. Mitotic indices (MI) of growths and subepithelial mucous cells were zero, MI of ciliated mantle epithelium reached 0.07%. The lesions were areas of strongly altered mucous cells of mantle epithelium and were non-neoplastic.  相似文献   

5.
Perlucin is an important functional protein that regulates shell and pearl formation. In this study, we cloned the perlucin gene from the freshwater pearl mussel Hyriopsis cumingii, designated as Hcperlucin. The full-length cDNA transcribed from the Hcperlucin gene was 1460 bp long, encoding a putative signal peptide of 20 amino acids and a mature protein of 141 amino acids. The mature Hcperlucin peptide contained six conserved cysteine residues and a carbohydrate recognition domain, similar to other members of the C-type lectin families. In addition, a “QPS” and an invariant “WND” motif near the C-terminal region were also found, which are extremely important for polysaccharide recognition and calcium binding of lectins. The mRNA of Hcperlucin was constitutively expressed in all tested H. cumingii tissues, with the highest expression levels observed in the mantle, adductor, gill and hemocytes. In situ hybridization was used to detect the presence of Hcperlucin mRNA in the mantle, and the result showed that the mRNA was specifically expressed in the epithelial cells of the dorsal mantle pallial, an area known to express genes involved in the biosynthesis of the nacreous layer of the shell. The significant Hcperlucin mRNA expression was detected on day 14 post shell damage and implantation, suggesting that the Hcperlucin might be an important gene in shell nacreous layer and pearl formation. The change of perlucin expression in pearl sac also confirmed that the mantle transplantation results in a new expression pattern of perlucin genes in pearl sac cells that are required for pearl biomineralization. These findings could help better understanding the function of perlucin in the shell and pearl formation.  相似文献   

6.
The hemocytes of Mytilus californianus are of three types: small and large basophils and large granular acidophils. The basophils contain lysosomal enzymes and phagocytose colloidal carbon. Agglutinins for yeast and human A Rh+ve erythrocytes are present in plasma, but are not needed for effective phagocytosis; in vitro both acidophilic and basophilic hemocytes rapidly phagocytose these particles. Plasma proteins, analyzed electrophoretically, are under strong homeostatic control. When Mya arenaria mantle is placed orthotopically on M. californianus mantle, the implant is invaded by host hemocytes in a manner consistent with that described in other published reports on molluscan graft rejection. Steady state is achieved by 26 days postimplant. Second- and third-set implants are rejected more rapidly than are first-set implants, but this is not a specific response. Third-set implants elicit a host cellular response that is more localized than the response to first-set implants. These data do not permit conclusions with respect to memory in these molluscan immune responses, but do imply a qualitative “improvement” in this quasi-immune response of M. californianus.  相似文献   

7.
A simple differential method based on measurement of an intracellular pigment of Aspergillus wentii was developed for estimation of the individual growths of two fungi, Trichoderma reesei and A. wentii, in mixed-culture fermentation of an insoluble cellulosic substrate.  相似文献   

8.
Scanning and transmission electron microscopy were utilized in studying the cephalic abnormalities of the tu-h strain of Drosophila melanogaster. Abnormalities, appearing as protuberances (growths) of different shapes and sizes, were observed only on or in close proximity to receptor cites. Compound eyes of some flies, besides having such protuberances, either had modified corneal lenses or were absent altogether. Cuticles of the growths were thinner than that of the normal surrounding layer. The epidermal cells associated with setae on the growths or underlying modified corneal lenses remained undifferntiated. Both setae and growths lacked innervation. The receptor portions (retinular sensory cells and secondary pigment cells) of the abnormal compound eye, where the dioptric portions were replaced by protuberances or remained undifferentiated, were unaffected by the mutation. Nuclei of several cells, including oenocytes and fat bodies, close to or underlying epidermal cells of abnormalities, were large and contained compact nucleoli without nucleonemas. Viruslike particles were observed in several nuclei of growth cells. It was concluded from the present study that the alterations induced by the mutation can be only a localized phenomenon restricted to at least several cephalic epidermal cells and/or their derivatives.  相似文献   

9.
Explants and swabs from the pericardium and mantle of three strains of Biomphalaria glabrata, two of them resistant to infection with Schistosoma mansoni, have yielded small amoebae, 3–5μm in diameter, in culture. These amoebae have been grown axenically through > 50 passages to date. The amoebae form cysts in dense cultures. When mixed with S. mansoni mother sporocysts in vitro, the amoebae adhere to and kill the trematodes within several hours. For 1–2 days thereafter, the amoebae proliferate rapidly at a generation time of about 5 hr, then return to normal growth. Sonically disrupted sporocysts also induce proliferation. Live sporocysts do not attract the amoebae or emit soluble substances which influence amoebal growth. Amoebae also adhered to and killed S. mansoni daughter sporocysts and cells derived from B. glabrata embryos; however, they did not harm S. mansoni cercariae or rediae of other trematode species. The proportion of mantle explants yielding amoebae was significantly higher (P<0.05) in one of the resistant snail strains than in the susceptible strain; however, whether amoebae contribute to snail resistance is unknown. Exposure of snails to S. mansoni miracidia did not influence the proportion of snails yielding amoebae.  相似文献   

10.
11.
Transition of bacteria to cell wall deficient L-forms in response to stress factors has been assumed as a potential mechanism for survival of microbes under unfavorable conditions. In this article, we provide evidence of paradoxal survival through L-form conversion of E. coli high cell density population after lethal treatments (boiling or autoclaving). Light and transmission electron microscopy demonstrated conversion from classical rod to polymorphic L-form shape morphology and atypical growths of E. coli. Microcrystal formations observed at this stage were interpreted as being closely linked to the processes of L-form conversion and probably involved in the general phenomenon of protection against lethal environment. Identity of the morphologically modified L-forms as E. coli was verified by species specific DNA-based test. Our study might contribute to a better understanding of the L-form phenomenon and its importance for bacterial survival, as well as provoke reexamination of the traditional view of killing strategies against bacteria.  相似文献   

12.
13.
Germination and growth patterns were studied of germlings and sporelings of eight species of marine algae when grown on diatom mucilage. Whilst growths of green and brown algae were enhanced, growth of the red algae was inhibited. Morphologically abnormal sporelings of Ulva lactuca L. and Gigartina stellata (Stackh.) Batt. were obtained in the presence of the mucilage.  相似文献   

14.
In the first half of gestation, mouse yolk sac contains levels of N-acetyl-β-hexosaminidase activity and a ratio of N-acetyl-β-hexosaminidase: β-glucuronidase much higher than those of other embryonic tissues or the decidua. The properties of the yolk sac enzyme are very similar to those in the other tissues, suggesting that the observed difference in activity is quantitative rather than qualitative. In blastocyst cultures, the vesicular growths derived from the inner cell mass possess patterns of N-acetyl-β-hexosaminidase activity similar to yolk sac in vivo, but different from trophoblast cells developing in the same cultures. It is therefore proposed that the vesicular growths contain at least some differentiated yolk sac cells.  相似文献   

15.
Forty-two Populus spp. clones, Eucalyptus benthamii, and seven tree species native to North Carolina were evaluated for survival and height growth through the establishment phase at two municipal wastewater application sites. Groundwater was monitored at each site to determine if establishment of the species trials resulted in exceedances of nutrient mitigation requirements. At the Gibson Wastewater Treatment Facility, 26 Populus clones had 100 % survival, with mean height growths ranging between 152 to 260 cm, and basal diameters ranging between 11.4 and 28.8 mm. Green ash, planted in 2011 and 2012, had high survivorship (>95 %) with first year mean height growth of 30?±?28 cm (2012) and second year mean height growth of 101?±?52 cm (2011). Basal diameter for green ash was 33.3?±?12.6 mm. E. benthamii had moderate survivorship (>77 %) and first year mean height growth of 47?±?27 cm. At the Jacksonville Wastewater Treatment Facility, green ash and bald cypress had high survivorship (>96 %), first year mean height growths of 14?±?25 cm and 27?±?16 cm, and basal diameters of 13.1?±?3.9 mm and 11.6?±?4.8 mm, respectively. Survivorship for 12 Populus clones ranged from 50 and 94 % with mean first year height growths between 58 to 121 cm, and basal diameters between 6.8 and 12.5 mm. E. benthamii had low survivorship (43 %) with mean first year height growths of 17?±?17 cm and basal diameters of 12.0?±?7.7 mm. Groundwater concentrations of NO3?+?NO2 and N-NH4 remained below regulatory requirements at both sites with one exceedance in February 2012 in Jacksonville, NC. The results show that some Populus clones are excellent candidates for woody biomass production on municipal wastewater application fields. Native green ash and bald cypress are also good candidates, but these trees may require longer rotations than Populus to achieve similar biomass yields.  相似文献   

16.
The intertidal gastropods Gibbula cineraria (L.), Nucella lapillus (L.), and Littorina littorea (L.) have been investigated. Animals that had attached to a plastic surface under sea water were exposed to air and rapidly frozen. Fluid was found to be retained within the mantle cavity in contact with the gill. For each species the weight of the mantle cavity fluid retained in air was related to the whole weight of the animal. There was no significant difference between the weight of fluid held by animals in the laboratory and that held by animals on the shore 2 h after aerial exposure. The oxygen consumption of inactive individuals in air was measured by two techniques which did not produce significantly different results. The aerial oxygen consumption of all three species was lowered by the loss of mantle cavity fluid. This also reduced the temperature coefficient. A correlation is suggested between a large weight of mantle cavity fluid, the presence of a gill in the mantle cavity and a large reduction in oxygen consumption upon the loss of fluid.  相似文献   

17.
18.
A new protozoan of the genus Perkinsus is described from the muscle and hemolymph of the blacklip abalone, Haliotis ruber, from South Australia. It occurs in the muscle of the adductor and mantle, and free and in brownish masses in the hemolymph. Cells cultured in thioglycollate medium produced a prezoosporangium which stained blue-black with iodine. The parasite differs from Perkinsus marinus, the only other member of the class, in having a much larger trophozoite, an eosinophilic vacuoplast when present, a short discharge tube, and appears to be uninfective to oysters.  相似文献   

19.
20.
Mollusc shell biomineralisation involves a variety of organic macromolecules (matrix proteins and enzymes) that control calcium carbonate (CaCO3) deposition, growth of crystals, the selection of polymorph, and the microstructure of the shell. Since the mantle and the hemocytes play an important role in the control of shell formation, primary cell cultures have been developed to study the expression of three biomineralisation genes recently identified in the abalone Haliotis tuberculata: a matrix protein, Lustrin A, and two carbonic anhydrase enzymes. Mantle cells and hemocytes were successfully maintained in primary cultures and were evaluated for their viability and proliferation over time using a semi-automated assay (XTT). PCR and densitometric analysis were used to semi-quantify the gene expression and compare the level of expression in native tissues and cultured cells. The results demonstrated that the three genes of interest were being expressed in abalone tissues, with expression highest in the mantle and much lower in the hemocytes and the gills. Biomineralisation genes were also expressed significantly in mantle cells, confirming that primary cultures of target tissues are suitable models for in vitro investigation of matrix protein secretion.  相似文献   

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