Pattern of Substrate Preferences of Free Living Protists (Myxomycetes) in Decaying Wood

AbstractProteolytic activities in extracts from three nematodes, the plant parasites Heterodera glycines and Meloidogyneincognita, and the free-living Panagrellus redivivus, were surveyed for substrate preferences using a battery of seven FRET-modified peptide substrates, all derived from members of the large FMRF-amide like peptide (FLP) family in nematodes. Overall protease activity in P. redivivus was four- to fivefold greater than in either of the parasites, a result that might reflect developmental differences. Digestion of the M. incognita FLP KHEFVRFa (substrate Abz-KHEFVRF-Y(3-NO2)a) by M. incognita extract was sevenfold greater than with H. glycines extract and twofold greater than P. redivivus, suggesting species-specific preferences. Additional species differences were revealed upon screening 12 different protease inhibitors. Two substrates were used in the screen, Abz-KHEFVRF-Y(3-NO2)a and Abz-KPSFVRF-Y(3-NO2)a), which was digested equally by all three species. The effects of various inhibitor, substrate and extract source combinations on substrate digestion suggest that M. incognita differs significantly from P. redivivus and H. glycines in its complement of cysteine proteases, particularly cathepsin L-type protease.

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On the Morphology and Life History of Aproctonema entomophagum Keilin, a Nematode Parasite in the Larvae of Sciara pullula Winn. (Diptera—Nematocera)

Parasitology ◽

10.1017/s003118200001948x ◽

1933 ◽

Vol 25 (3) ◽

pp. 285-295 ◽

Cited By ~ 7

Author(s):

D. Keilin ◽

V. C. Robinson

Keyword(s):

Life History ◽

Systematic Position ◽

Egg Laying ◽

Nematode Parasite ◽

Free Living ◽

The Family ◽

Two Generations ◽

History Of ◽

Decaying Wood

1. An account is given of Aproctonema entomophagum Keilin 1917, a Nematode parasite of the larvae of a Mycetophilid fly, Sciara pullula Winn., inhabiting decaying wood.2. The life history of this parasite is remarkable in the following respects:(a) The free-living stage is very short.(b) Both sexes are parasitic.(c) The usual host is the larva of the fly, from which the parasite escapes by actively breaking through the skin; but some parasites may be carried through to the imagines, from which they escape largely by the aid of the egg-laying movements provoked by them in the flies.3. Metamorphosis of the Sciara larva is delayed by the parasitism, so that at least two generations of Nematodes may be found in one host.4. All the parasitised imagines so far examined have been females.5. The systematic position of Aproctonema is discussed, the conclusion being that this worm and its near relative, Tetradonema plicans Cobb 1919, represent two closely allied genera of the family Mermithidae, but are not synonymous with Mermis. It is proposed to dispense with the family Tetra-donematidae Cobb.

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New species of Augochlora (Oxystoglossella) Eickwort (Hymenoptera; Apoidea) from Northeastern Brazil with an identification key for the region

Zootaxa ◽

10.11646/zootaxa.4802.2.3 ◽

2020 ◽

Vol 4802 (2) ◽

pp. 261-293

Author(s):

ANDERSON LEPECO ◽

RODRIGO BARBOSA GONÇALVES

Keyword(s):

New Species ◽

Single Species ◽

Northeastern Brazil ◽

Northeastern Region ◽

Substrate Preferences ◽

Caatinga Biome ◽

Three New Species ◽

Nesting Substrate ◽

Decaying Wood ◽

First Time

Within Augochlorini, Augochlora Smith is one of the most speciose genera, with 118 species, and widely distributed groups, occurring from Argentina to Canada. The genus has a remarkable range of social behaviors and nesting substrate preferences. There are two recognized extant subgenera: Augochlora s.s., whose species nest in decaying wood cavities and Oxystoglossella, whose species nest in soil. To date, a single species revision is available for Central Argentina and Uruguay. In the present study we provide a revision of Oxystoglossella species occurring in Northeastern Brazil including the description of three new species: Augochlora bipunctata sp. nov., Augochlora modica sp. nov. and Augochlora tenax sp. nov. Herein Halictus eucnemis Vachal is resurrected from synonymy with Augochlora thalia Smith, and the lectotype of Halictus hemitomes Vachal is presently designated. Augochlora aurinasis is cited for Brazil for the first time. A key to the six species of Oxystoglossella occurring at Northeastern region in Brazil is provided. The three new species are apparently restricted to this region, being one of them probably linked to the Caatinga biome.

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The analysis of environmental space conditions for bryoflora forming in artificial pine communities of the Buzuluksky pine forest and the Krasnosamarsky forest

Samara Journal of Science ◽

10.17816/snv2021102102 ◽

2021 ◽

Vol 10 (2) ◽

pp. 18-23

Author(s):

Yana Andreevna Bogdanova ◽

Nataliya Vladimirovna Prokhorova ◽

Lyudmila Mikhailovna Kavelenova

Keyword(s):

Nitrogen Supply ◽

Pine Forest ◽

Projective Cover ◽

Significant Similarity ◽

Substrate Preferences ◽

Environmental Space ◽

Species Similarity ◽

Decaying Wood ◽

Specific Manifestation ◽

Space Conditions

The paper deals with ecological conditions and peculiarities of bryoflora of artificial pine communities of the Buzuluksky pine forest and the Krasnosamarsky forest. The authors have revealed that the pine plantings of the Buzuluksky pine forest are characterized by a lower soil moisture and nitrogen supply than similar communities of the Krasnosamarsky forest in accordance with the criteria of D.N. Tsyganov scales. In addition, all communities belonging to the same territory show differences in the acidity and salt regime of soils as well as in moisture contrasts. The differences seem to be the result of a specific manifestation of parallel multidirectional successional processes (afforestation and steppe formation). For the bryofloras of the studied artificial pine communities, a significant similarity level (Czekanowski-Srensen index of 0,7) and close values of the projective cover and vitality of bryophytes have been shown. However, the substrate preferences of bryophytes are significantly different: 85% of the species grow on soil in the Buzuluksky pine forest, while 52% of the species grow on soil and 39% of the species grow on decaying wood in the Krasnosamarsky forest. In addition, more intensive sporulation of bryophytes has been noted in artificial pine communities of the Krasnosamarsky forest and the share of dominant species in the projective cover is 47,7% there, and their share is 83,4% in the Buzuluksky pine forest. The authors have suggested that genetic polymorphism should underlie the revealed differences in the species similarity of bryofloras. Its manifestation is influenced, among other things, by the stage of ecological succession of plant communities in which bryophytes grow. It is the result of the implementation of strategies for bryophytes adaptation to existing conditions and reflects the stage of bryoflora formation.

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Ultrastructure of neuromuscular relationships in the canine heartworm (dirofilaria immitis)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143018 ◽

1986 ◽

Vol 44 ◽

pp. 278-279

Author(s):

W. L. Steffens ◽

Nancy B. Roberts ◽

J. M. Bowen

Keyword(s):

Dirofilaria Immitis ◽

Domestic Dogs ◽

Structural Description ◽

Pharmacological Effects ◽

Free Living ◽

Canine Heartworm ◽

The World ◽

Synaptic Region ◽

Muscle Innervation ◽

Insight Into

The canine heartworm is a common and serious nematode parasite of domestic dogs in many parts of the world. Although nematode neuroanatomy is fairly well documented, the emphasis has been on sensory anatomy and primarily in free-living soil species and ascarids. Lee and Miller reported on the muscular anatomy in the heartworm, but provided little insight into the peripheral nervous system or myoneural relationships. The classical fine-structural description of nematode muscle innervation is Rosenbluth's earlier work in Ascaris. Since the pharmacological effects of some nematacides currently being developed are neuromuscular in nature, a better understanding of heartworm myoneural anatomy, particularly in reference to the synaptic region is warranted.

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Lead and lead toxicity in domestic and free living birds

Avian Pathology ◽

10.1080/03079450301777 ◽

2003 ◽

Vol 32 (1) ◽

pp. 3-13 ◽

Cited By ~ 1

Author(s):

N. De Francisco ◽

N. De Francisco

Keyword(s):

Lead Toxicity ◽

Free Living

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Platelet Aggregation in Finnish Men and Its Relation to Fatty Acids in Platelets, Plasma and Adipose Tissue

Thrombosis and Haemostasis ◽

10.1055/s-0038-1660071 ◽

1985 ◽

Vol 54 (03) ◽

pp. 563-569 ◽

Cited By ~ 19

Author(s):

M K Salo ◽

E Vartiainen ◽

P Puska ◽

T Nikkari

Keyword(s):

Fatty Acids ◽

Adipose Tissue ◽

Fatty Acid Composition ◽

Fatty Acid ◽

Platelet Aggregation ◽

Acid Composition ◽

Saturated Fatty Acids ◽

Free Living ◽

Ω3 Fatty Acids ◽

Induced Aggregation

SummaryPlatelet aggregation and its relation to fatty acid composition of platelets, plasma and adipose tissue was determined in 196 randomly selected, free-living, 40-49-year-old men in two regions of Finland (east and southwest) with a nearly twofold difference in the IHD rate.There were no significant east-southwest differences in platelet aggregation induced with ADP, thrombin or epinephrine. ADP-induced platelet secondary aggregation showed significant negative associations with all C20-C22 ω3-fatty acids in platelets (r = -0.26 - -0.40) and with the platelet 20: 5ω3/20: 4ω 6 and ω3/ ω6 ratios, but significant positive correlations with the contents of 18:2 in adipose tissue (r = 0.20) and plasma triglycerides (TG) (r = 0.29). Epinephrine-induced aggregation correlated negatively with 20: 5ω 3 in plasma cholesteryl esters (CE) (r = -0.23) and TG (r = -0.29), and positively with the total percentage of saturated fatty acids in platelets (r = 0.33), but had no significant correlations with any of the ω6-fatty acids. Thrombin-induced aggregation correlated negatively with the ω3/6ω ratio in adipose tissue (r = -0.25) and the 20: 3ω6/20: 4ω 6 ratio in plasma CE (r = -0.27) and free fatty acids (FFA) (r = -0.23), and positively with adipose tissue 18:2 (r = 0.23) and 20:4ω6 (r = 0.22) in plasma phospholipids (PL).The percentages of prostanoid precursors in platelet lipids, i. e. 20: 3ω 6, 20: 4ω 6 and 20 :5ω 3, correlated best with the same fatty acids in plasma CE (r = 0.32 - 0.77) and PL (r = 0.28 - 0.74). Platelet 20: 5ω 3 had highly significant negative correlations with the percentage of 18:2 in adipose tissue and all plasma lipid fractions (r = -0.35 - -0.44).These results suggest that, among a free-living population, relatively small changes in the fatty acid composition of plasma and platelets may be reflected in significant differences in platelet aggregation, and that an increase in linoleate-rich vegetable fat in the diet may not affect platelet function favourably unless it is accompanied by an adequate supply of ω3 fatty acids.

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