121. The molecular weight range of nematode allergens - Hogarth-Scott, R. S.
Gel-filtration on Sephadex, of Ascaris, Nippostrongylus, Toxocara and Toxascaris antigens revealed that the allergenic components had a molecular weight range of 10,000–50,000. Allergenicity was assessed by homologous passive cutaneous anaphylaxis, to detect reagins in man and reagin-like antibodies in the rat and rabbit. It is suggested that nematodes can provoke a Type I allergic reaction in man, rat and the rabbit.

122. Nematodos del género Aphelenchoides de interés fitopatológico y su distribución en España - Bello Pérez, Antonio; Escuer, M.
Se revisan las referencias existentes en España sobre los nematodos fitoparásitos del género Aphelenchoides, algunas de cuyas especies pueden ser patógenos de, arroz, champiñon, fresa y plantas ornamentales. Se han encontrado en España A. bicaudatus, A. blastophthorus, A. composticola, A. fragariae y A.ritzemabosi solo en Canarias. Se elabora una clave para facilitar la identificación de las especies patógenas del género Aphelenchoides y se señalan las características morfológicas, biológicas, los hospedadores, sintomatología y la distribución, tanto a nivel mundial como en España. Se resalta la importancia de las medidas preventivas como una de las prácticas más adecuadas para evitar las infestaciones...

123. Collagenase Production by Nematode-Trapping Fungi † - Schenck, Susan; Chase, Theodore; Rosenzweig, W. D.; Pramer, David
A number of species of nematode-trapping fungi, which capture and digest nematodes having keratin and collagen in their cuticles, were tested for the ability to produce extracellular collagenase and keratinase. Collagenase, which is active on ichthyocol, earthworm collagen, and procollagen from chicken embryo fibroblasts, was found in the growth medium of all tested species; keratinase was not found. The enzyme from Arthrobotrys amerospora was concentrated by precipitation with (NH4)2SO4 and further purified by adsorption on collagen at 0°C. The collagenase was active over a pH range of 2.5 to 10.0. It was not inactivated by dialysis against ethylenediaminetetraacetic acid for...

124. Collagenase Production by Nematode-Trapping Fungi â?  - Schenck, Susan; Chase, Theodore; Rosenzweig, W. D.; Pramer, David
A number of species of nematode-trapping fungi, which capture and digest nematodes having keratin and collagen in their cuticles, were tested for the ability to produce extracellular collagenase and keratinase. Collagenase, which is active on ichthyocol, earthworm collagen, and procollagen from chicken embryo fibroblasts, was found in the growth medium of all tested species; keratinase was not found. The enzyme from Arthrobotrys amerospora was concentrated by precipitation with (NH4)2SO4 and further purified by adsorption on collagen at 0°C. The collagenase was active over a pH range of 2.5 to 10.0. It was not inactivated by dialysis against ethylenediaminetetraacetic acid for...

125. Biogenic magnetite in the nematode caenorhabditis elegans. - Cranfield, Charles G; Dawe, Adam; Karloukovski, Vassil; Dunin-Borkowski, Rafal E; de Pomerai, David; Dobson, Jon
The nematode Caenorhabditis elegans is widely used as a model system in biological research. Recently, examination of the production of heat-shock proteins in this organism in response to mobile phone-type electromagnetic field exposure produced the most robust demonstration to date of a non-thermal, deleterious biological effect. Though these results appear to be a sound demonstration of non-thermal bioeffects, to our knowledge, no mechanism has been proposed to explain them. We show, apparently for the first time, that biogenic magnetite, a ferrimagnetic iron oxide, is present in C. elegans. Its presence may have confounding effects on experiments involving electromagnetic fields as...

126. Nematodos asociados a madera y árboles de coníferas en pinares españoles - Arias, M.; Escuer, M.; Bello Pérez, Antonio
Como consecuencia de la detección del nematodo de la seca de los pinos, Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle en la península de Setúbal (Portugal) se planteó el estudio de los nematodos asociados a madera de coníferas, con especial atención a las especies del género Bursaphelenchus en industrias madereras, Puntos de Inspección Fronteriza (PIFs) y árboles de confieras en España. Los muestreos se realizaron mediante la coordinación del Ministerio de Agricultura, Pesca y Alimentación por las autoridades fitosanitarias de las Comunidades Autónomas. Se ha seguido para el estudio la normativa de la UE, habiéndose estudiado más de 6.000 muestras desde...

127. Endo-?-1,4-Glucanase Expression in Compatible Plant–Nematode Interactions - Goellner, Melissa; Wang, Xiaohong; Davis, Eric L.
Cyst nematodes and root-knot nematodes elaborately transform cells within the vascular cylinders of plant roots into enlarged, multinucleate, and metabolically active feeding cells. The giant cells of root-knot nematodes are formed by repeated karyokinesis uncoupled from cytokinesis, whereas the syncytia formed by cyst nematodes arise from coordinated cell wall dissolution and the coalescing of cell cytoplasm of adjacent cells. Both giant cells and syncytia undergo extensive cell wall architectural modifications, including thickening and the formation of numerous ingrowths that increase the plasmalemma surface area for solute uptake. The origin of enzymes involved in these cell wall modifications has been the...

128. Endo-β-1,4-Glucanase Expression in Compatible Plantâ??Nematode Interactions - Goellner, Melissa; Wang, Xiaohong; Davis, Eric L.
Cyst nematodes and root-knot nematodes elaborately transform cells within the vascular cylinders of plant roots into enlarged, multinucleate, and metabolically active feeding cells. The giant cells of root-knot nematodes are formed by repeated karyokinesis uncoupled from cytokinesis, whereas the syncytia formed by cyst nematodes arise from coordinated cell wall dissolution and the coalescing of cell cytoplasm of adjacent cells. Both giant cells and syncytia undergo extensive cell wall architectural modifications, including thickening and the formation of numerous ingrowths that increase the plasmalemma surface area for solute uptake. The origin of enzymes involved in these cell wall modifications has been the...

129. NEMATODE PARASITES FROM VESPERTILIO ORIENTALIS WALLIN - OHBAYASHI, Masashi; KAMIYA, Haruo
Three nematode parasites of Vespertilio orientalis are described. Molinostrongylus tsuchiyai sp. n. is characterized by a lack of synlophes, well-developed lateral alae (0.020～0.030 mm in width), and spicules with a spur-like structure. Litomosa japonica sp. n. is characterized by a very long esophagus (more than 0.8 mm long). Litomosa sp., female specimens, is differentiated from L. japonica sp. n. by a shorter esophagus and three caudal projections.

130. Prevalence of intestinal nematodes in alcoholic patients - Zago-Gomes,Maria P.; Aikawa,Kiyoshi F.; Perazzio,Sandro F.; Gonçalves,Carlos S.; Pereira,Fausto E.L.
We report the results of a retrospective study on the frequency of intestinal nematodes among 198 alcoholic and 440 nonalcoholic patients at the University Hospital Cassiano Antonio Moraes in Vitória, ES, Brazil. The control sample included 194 nonalcoholic patients matched according to age, sex and neighborhood and a random sample of 296 adults admitted at the same hospital. Stool examination by sedimentation method (three samples) was performed in all patients. There was a significantly higher frequency of intestinal nematodes in alcoholics than in controls (35.3% and 19.2%, respectively), due to a higher frequency of Strongyloides stercoralis (21.7% and 4.1%, respectively)....

131. Abomasal Nematodes in Cattle in Ontario - Slocombe, J. O. D.
During 1970, 93 abomasa from cattle in Ontario were examined, and from 63 of these abomasa nematode species of the genera Ostertagia, Haemonchus and/or Trichostrongylus axei were recovered. The abomasa were from cattle six months to two years of age and were collected either from the postmortem room at the Ontario Veterinary College or from two abattoirs near Guelph. The numbers of worms per abomasum were estimated and their genera were identified from a one-twentieth volume of the washings and contents. The prevalence of Ostertagia species was estimated by examining random samples of adult male worms. Morphological variations in the...

132. Abomasal Nematodes in Cattle in Ontario - Slocombe, J. O. D.
During 1970, 93 abomasa from cattle in Ontario were examined, and from 63 of these abomasa nematode species of the genera Ostertagia, Haemonchus and/or Trichostrongylus axei were recovered. The abomasa were from cattle six months to two years of age and were collected either from the postmortem room at the Ontario Veterinary College or from two abattoirs near Guelph. The numbers of worms per abomasum were estimated and their genera were identified from a one-twentieth volume of the washings and contents. The prevalence of Ostertagia species was estimated by examining random samples of adult male worms. Morphological variations in the...

133. Phylogeny of Wolbachia in filarial nematodes. - Bandi, C; Anderson, T J; Genchi, C; Blaxter, M L
Intracellular bacteria have been observed in various species of filarial nematodes (family Onchocercidae). The intracellular bacterium of the canine filaria Dirofilaria immitis has been shown to be closely related to Wolbachia, a rickettsia-like micro-organism that is widespread among arthropods. However, the relationships between endosymbionts of different filariae, and between these and the arthropod wolbachiae, appear not to have been studied. To address these issues we have examined ten species of filarial nematodes for the presence of Wolbachia. For nine species, all samples examined were PCR positive using primers specific for the ftsZ gene of Wolbachia. For one species, the examined...

134. Differential vascularization of nematode-induced feeding sites - Hoth, Stefan; Stadler, Ruth; Sauer, Norbert; Hammes, Ulrich Z.
Sedentary nematodes are destructive plant pathogens that cause significant yield losses. In the roots of their host plants, cyst nematodes (CNs) and root-knot nematodes (RKNs) induce different, highly specialized feeding sites—syncytia or giant cells (GCs), respectively—to optimize nutrient uptake. We compared the mechanisms by which nutrients are delivered from the model host plant, Arabidopsis, to GCs induced by the RKN Meloidogyne incognita or to syncytia induced by the CN Heterodera schachtii. From previous work, syncytia were known to be symplastically connected to newly formed host phloem composed of sieve elements (SEs) and companion cells. Here we studied the formation of...

135. Abstract - Nematode Caenorhabditis Elegans; Nathan A. Dunn; John S. Conery; Shawn R. Lockery
The connectivity of the nervous system of the nematode Caenorhabditis elegans has been described completely, but the analysis of the neuronal basis of behavior in this system is just beginning. Here, we used an optimization algorithm to search for patterns of connectivity sufficient to compute the sensorimotor transformation underlying C. elegans chemotaxis, a simple form of spatial orientation behavior in which turning probability is modulated by the rate of change of chemical concentration. Optimization produced differentiator networks with inhibitory feedback among all neurons. Further analysis showed that feedback regulates the latency between sensory input and behavior. Common patterns of connectivity...

136. Abstract - Nematode Caenorhabditis Elegans; Nathan A. Dunn; John S. Conery; Shawn R. Lockery
The connectivity of the nervous system of the nematode Caenorhabditis elegans has been described completely, but the analysis of the neuronal basis of behavior in this system is just beginning. Here, we used an optimization algorithm to search for patterns of connectivity sufficient to compute the sensorimotor transformation underlying C. elegans chemotaxis, a simple form of spatial orientation behavior in which turning probability is modulated by the rate of change of chemical concentration. Optimization produced differentiator networks with inhibitory feedback among all neurons. Further analysis showed that feedback regulates the latency between sensory input and behavior. Common patterns of connectivity...

137. Recovery of parasitic nematodes from fish by digestion or elution. - Jackson, G J; Bier, J W; Payne, W L; McClure, F D
Two methods, digestion and elution, were used to recover parasitic nematodes from 470 flatfish belonging to species in the family Pleuronectidae. Samples of similar fish were collected from market lots; half of each sample was subjected to digestion, and half was subjected to elution (sedimentation). The edible (flesh) and the inedible (viscera) portions of each fish were analyzed separately. The total number of nematodes recovered by digestion was 1,110, which was not significantly greater than the 922 nematodes recovered by elution. However, digestion recovered 1,062 nematodes of the anisakine genera Anisakis and Phocanema, which are potentially pathogenic for human consumers...

138. Recovery of parasitic nematodes from fish by digestion or elution. - Jackson, G J; Bier, J W; Payne, W L; McClure, F D
Two methods, digestion and elution, were used to recover parasitic nematodes from 470 flatfish belonging to species in the family Pleuronectidae. Samples of similar fish were collected from market lots; half of each sample was subjected to digestion, and half was subjected to elution (sedimentation). The edible (flesh) and the inedible (viscera) portions of each fish were analyzed separately. The total number of nematodes recovered by digestion was 1,110, which was not significantly greater than the 922 nematodes recovered by elution. However, digestion recovered 1,062 nematodes of the anisakine genera Anisakis and Phocanema, which are potentially pathogenic for human consumers...

139. MSP Dynamics Drives Nematode Sperm Locomotion - Wolgemuth, Charles W.; Miao, Long; Vanderlinde, Orion; Roberts, Tom; Oster, George
Most eukaryotic cells can crawl over surfaces. In general, this motility requires three sequential actions: polymerization at the leading edge, adhesion to the substrate, and retraction at the rear. Recent in vitro experiments with extracts from spermatozoa from the nematode Ascaris suum suggest that retraction forces are generated by depolymerization of the major sperm protein cytoskeleton. Combining polymer entropy with a simple kinetic model for disassembly we propose a model for disassembly-induced retraction that fits the in vitro experimental data. This model explains the mechanism by which disassembly of the cytoskeleton generates the force necessary to pull the cell body...

140. MSP Dynamics Drives Nematode Sperm Locomotion - Wolgemuth, Charles W.; Miao, Long; Vanderlinde, Orion; Roberts, Tom; Oster, George
Most eukaryotic cells can crawl over surfaces. In general, this motility requires three sequential actions: polymerization at the leading edge, adhesion to the substrate, and retraction at the rear. Recent in vitro experiments with extracts from spermatozoa from the nematode Ascaris suum suggest that retraction forces are generated by depolymerization of the major sperm protein cytoskeleton. Combining polymer entropy with a simple kinetic model for disassembly we propose a model for disassembly-induced retraction that fits the in vitro experimental data. This model explains the mechanism by which disassembly of the cytoskeleton generates the force necessary to pull the cell body...

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