bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunochemical analysis ofTaenia taeniaeformisantigens expressed inEscherichia coli
Authors: Bowtell D. D. L. , Saint R. B. , Rickard M. D. , Mitchell G. F.
Published: June 2009

Previously we reported the isolation of severalEscherichia coliclones expressing fragments ofTaenia taeniaeformisantigens as β-galactosidase fused proteins (Bowtell, Saint, Rickard & Mitchell, 1984). Here we describe the isolation of additional antigen-expressing clones from a larval cDNA library and the assignment of these clones to 7 antigen families. These were isolated with a polyspecific rabbit antiserum raised to the oncosphere. Since this serum was capable of reacting with a large number of antigens, it was important to develop techniques for rapidly determining the identity of the nativeT. taeniaeformismolecule corresponding to a cloned antigen gene. These included active immunization of rabbits with fused proteins and several techniques involving affinity purification on immobilized fused proteins. The reactivity of the antigen-positive clones with sera from humans infected with related parasites was also assessed. Finally, immunization of mice with several fused proteins failed to protect against subsequent infection, although antigens previously identified as candidate host-protective antigens (Bowtell, Mitchell, Anders, Lightowlers & Rickard, 1983) have yet to be identified in the expression library.
The presence of agglutinating antibody in the IgM immunoglobulin fraction of rabbit antiserum during experimental African trypanosomiasis
Authors: Seed J. R. , Cornille Renee L. , Risby E. L. , Gam A. A.
Published: June 2009

The IgM levels in rabbits infected withTrypanosoma gambienseare raised. Agglutinating antibody has been found in the IgM immunoglobulin fraction of sera obtained from these infected rabbits. Agglutinating antibody was first found in the IgM fraction and later in the infection appeared in both the IgM and IgG fractions. Precipitating antibody to blood trypanosome antigens was found solely in the IgG fraction.

On the basis of the data presented here a working hypothesis is developed to explain the raised IgM immunoglobulin levels found in the sera of rabbits and humans infected withT. gambiense.
The ultrastructure of the intestinal epithelium of Metastrongylus sp. (Nematoda: Strongyloidea)
Authors: Jenkins T. , Erasmus David A.
Published: June 2009

Ultrastructural observations on the intestine of Metastrongylus sp. have shown that it is composed of a single layer of epithelial cells each with a basally placed nucleus and resting on a basement layer. The basal plasma membrane of each cell is highly infolded and at the cell apex the lateral plasma membranes of adjacent cells are thickened to form a terminal bar.

The brush border consists of numerous microvilli which possess dilated tips. The tips contain a granular material and the evidence obtained suggests that they are released into the lumen indicating a form of micro-apocrine secretion. Golgi complexes, glycogen, lipid droplets and granular endoplasmic reticulum are present in the intestinal cells. The Golgi complexes are associated with the production of an electron dense body. Other inclusions are cytolysome-like in their structure. The discharge of lamellar bodies into the intestinal lumen is described and the role of the intestine in secretion, absorption, and excretion is discussed.

The authors wish to acknowledge the co-operation and facilities provided by Professor J. Brough in the Department of Zoology and Mr J. H. M. Hughes (Veterinary Officer) for allowing unrestricted access to infected material at the Roath abattoir, Cardiff. Grateful acknowledgement is also expressed for the financial support given to one of us (T. J.) by the Pig Industry Development Authority. Any views expressed in this paper are not necessarily those of the Authority.

The authors also wish to express their appreciation of the excellent technical assistance provided by Mr T. W. Davies.
Babesia rodhaini infections in the rat after acute primary parasitaemia
Authors: Phillips R. S.
Published: June 2009

Babesia rodhaini remains in the blood of most rats from 2 to 12 months after the acute primary parasitaemia has subsided. By analogy with some trypanosome and malaria infections it is suggested that piroplasms may have the capacity for antigenic variation, thus allowing the parasite to survive in the host for so long albeit as a chronic infection. A population of B. rodhaini was isolated which was considerably less sensitive in passive transfer experiments to two pools of serum from recovered rats than the normal passage population.

I thank Dr S. F. Barnett for his advice during the work and Dr F. Hawking and my colleagues at Mill Hill for criticizing the manuscript. This work was carried out during the tenure of an Agricultural Research Council Studentship.
The protective activity of serum from immune rats againstBabesia rodhaini
Authors: Phillips R. S.
Published: June 2009

Sera pooled from rats which were immune toBabesia rodhainiinfection had demonstrable protective activity against the piroplasm in non-immune rats. When inoculated with parasites or close to the time of infection, antiserum caused a delay in the onset of patency but did not usually affect the course and severity of the patent parasitaemia in young rats. There were more survivors when antiserum was given in a series of small doses over a period rather than a single large inoculum at the time of infection. Serum from rats previously reinfected several times, when injected into infected rats during the early stages of patency, was followed by a rapid fall in parasite numbers. A severe secondary parasitaemia eventually ensued in these animals.

I would like to thank Dr S. F. Barnett for his advice during the work and Dr F. Hawking and my colleagues at Mill Hill for criticizing the manuscript. This work was carried out during the tenure of an Agricultural Research Council Studentship.
Digestion in the tick,Argas persicus,Oken.
Authors: Tatchell R. J.
Published: June 2009

1.Studies on the histological changes during digestion inArgas persicusreveal that the ingestion of blood is accompanied by the destruction of the existing gut epithelial cells.

2.The blood remains unlysed for 2–3 days while a new epithelium develops which contains cells that secrete a saliva-fast PAS-positive colloid that causes haemolysis.

3.Other epithelial cells remove the freed erythrocytic nuclei by phagocytosis.

4.Most of the gut cells then absorb protein from the lumen and intracellular digestion takes place leaving pure haematin granules as the waste product of the digestion of haemoglobin.

5.After the initial rapid phase of digestion only relatively few cells show signs of absorptive and digestive activity.

6.Absorption of protein is accompanied by increased alkaline phosphatase activity in the microvilli of the cell border; this activity is lost once absorption finishes and digestion begins.

7.Strong aminopeptidase activity can be demonstrated at the border of some of the protein vacuoles.

8.In vitrotests show that the gut proteinase is active only in the acid range with peaks at pH 2·6 and 3·8 and has aKmof 0·32 % with bovine serum albumin as substrate.

9.In vivodata show that digestion, after haemolysis has occurred, takes place in two phases; the first is rapid and lasts approximately 1–2 weeks and is followed by the second phase which is slow and remains constant until the next blood feed.

10.The proportion of the blood meal which remains after the rapid phase of digestion is determined by the sex and developmental stage of the tick and within each category it is constant and serves, in the absence of significant fat and glycogen reserves, as a food reserve.
Trypanosoma mochli, a trypanosome from an African lizard
Authors: Berghe L. van den , Chardome M. , Peel E.
Published: June 2009

The Mochlus fernandi lizards (Scincidae) from the Kivu province (Congo) around Lwiro, Katana, are infected with a broad leaf-like monomorphic trypanosome, Trypanosoma mochli. The high moisture requirements of M. fernandi, which resemble European salamanders, and the morphological similarity of T. mochli to amphibian trypanosomes point to an aquatic transmission and vector for this species.
Studies on the tapeworm Anoplocephala perfoliata (Goeze, 1782)
Authors: Lee D. L. , Tatchell R. J.
Published: June 2009

1. The exrectory system of Anoplocephala perfoliata has been re-described and shown to consist of a dorsal ‘network’ system of vessels to which the flame cells are connected and a ventral pair of longitudinal vessels linked only by a transverse vessel in each proglottid.

2. The two excretory systems unite only in the apical ramifying vessels of the scolex.

3. Alkaline phosphatase activity was demonstrated in the cuticular microvilli, the subcuticular region and in the excretory vessels.

4. Non-specific esterase, insensitive to 10−4m E 600, was located in the lappets and embryonated eggs and esterases, inhibited by 10−4m E600, in parts of the cuticle and subcuticular region and parenchyma.

5. Cholinesterases were found in the nervous system and in the reproductive ducts.

6. Aminopeptidase was found in the neck region, in the undifferentiated proglottids, the active testes and ovaries, the male reproductive ducts and in the region of high metabolic activity in the fringe of the proglottid.
Observations on the occurrence of the plerocercoids of Triaenophorus nodulosus (Pallas, 1781) (Cestoda: Pseudophyllidea) in the perch Perca fluviatilis L. of Llyn Tegid (Bala Lake), Merionethshire
Authors: Chubb James C.
Published: June 2009

The perch was the principal host for the plerocercoid of Triaenophorus nodulosus in Llyn Tegid.

Three stages of plerocercoid development were recognized: non-encapsuled developing plerocercoids, encapsuled but living mature plerocercoids, and dead encapsuled degenerate plerocercoids.

The stomach contents of the perch were analysed and planktonic crustaceans were found to be a significant part of the food from May to December. No change in diet in relation to length was found.

The period of occurrence of developing plerocercoids in the perch livers was March to June. This in relation to other evidence was shown to indicate the period of infection of the perch by the procercoids.

The three stages of plerocercoid development recognized were found to occur simultaneously in a few perch, and thus may represent infections acquired over three successive seasons.

There was no seasonal periodicity of occurrence of the plerocercoids in the perch.

All the perch examined were more or less equally infected by plerocercoids. There was no tendency for older, longer perch to be more heavily infected.

One to five capsules, normally containing one plerocercoid each, occurred in the livers of the infected perch.

For the perch examined there was a dynamic equilibrium between establishment of procercoids from the copepod host, and loss of plerocercoids by degeneration within the perch.

The mature plerocercoids form the reservoir of infection for the definitive host of T. nodulosus, the pike.
The dynamics of the host-parasite relationship
Authors: Donald A. D. , Dineen J. K. , Turner J. H. , Wagland B. M.
Published: June 2009

The studies presented in this paper describe the effects of control exerted by the immunological response of the host (sheep) on the developmental stages and fecundity of the parasite Nematodirus spathiger. Thirty Merino lambs, maintained worm-free, were randomly divided among three treatment groups each containing ten animals. The group 1 lambs were each given a single dose of 50,000 infective larvae, the group 2 animals were given a single dose of 130,000 infective larvae, and the group 3 animals were given twenty-five consecutive daily doses of 2000 infective larvae. Group fecundity was estimated by performing worm egg counts on daily faecal samples and development of the parasite burden was followed by carrying out differential worm counts on animals slaughtered at crucial stages during the infections. Total fecundity was greatest in group 1 and least in group 3 with group 2 intermediate. An inverse relationship between total fecundity and percentage retardation of development (percentage of 4th-stage larvae in the total worm burden) was demonstrated between the three treatment groups.

The results of the studies also show that control of the parasitic infection is mediated about threshold levels of immunological responsiveness and is expressed by (1) elimination at the infective (L3) stage, (2) retardation of development at the L4 stage, (3) reduction in egg production of the adult female, (4) elimination of adult worms, and (5) discrimination against the female in both the degree of retardation in the L4 stage and the extent of elimination in the adult stage.

Great variation in response was observed between individuals within treatment groups. The source of variation is attributed to differences in degree of antigenic disparity of the parasite with individual members of the heterozygous host population in which antigenic characters are not uniformly segregated.

The concept of ‘fitness’ of the parasitic species was introduced into the discussion to provide a rational interpretation of the results.

We are indebted to Dr S. S. Y. Young, Division of Animal Genetics, C.S.I.R.O., for advice and assistance with the statistical analyses, which were performed by Mrs M. Tonkin, and to Dr D. F. Stewart for his constructive criticism of the manuscript. Careful technical assistance was given by Mr E. Teleki and Misses Helen Giller and Berenice Merchant.
Gametogenesis and fertilization in the Mesozoan Dicyema aegira
Authors: Austin C. R.
Published: June 2009

Evidence is presented of a periodicity of oogenesis and spermatogenesis in D. aegira. Pauses in oogenesis were detected between successions of oogonial divisions; in spermatogenesis, the intervals appeared to be longer and the pauses came before division of primary spermatocytes. Regulation of division rates was such that between two and three times as many spermatozoa as oocytes were produced.

Observations indicated that spermatozoa emerged from the axial cell soon after their formation and made contact with oocytes early, often before these were fully grown. Properties of the oocyte cell membrane evidently precluded precocious sperm entry and the penetration of more than one spermatozoon.

Sincere thanks are due to Dr R. B. Short, who kindly made available all the material, and to Dr S. W. Fox and Dr C. B. Metz for the excellent facilities provided. This work was supported by P. H. S. Research Grant E 4749 (Institute of Allergy and Infectious Diseases) awarded to R. B. Short, and by N.A.S.A. Grant NsG–173–62 and N.S.F. Grant G–9150. Contribution No. 019 of the Institute for Space Biosciences.
The envelope surrounding Polymorphus minutus (Goeze, 1782) (Acanthocephala) during its development in the intermediate host, Gammarus pulex
Authors: Crompton D. W. T.
Published: June 2009

1. The envelope surrounding Polymorphus minutus during its development in Gammarus pulex has been found to be a capsule produced by a wound healing haemocytic reaction of the host. The haemocytic reaction is stimulated when the parasite stretches the connective tissue serosa of the host's gut.

2. The capsule is a thin, acellular structure, consisting of a protein-carbohydrate complex like that constituting host connective tissue. This material is produced and deposited by the haemocytes.

3. The ability of the haemocytes to produce this protein-carbohydrate material is considered to be the mechanism which ensures the growth of the capsule during the subsequent development of the parasite in the haemocoel.

4. A second layer appears within the capsule just before the parasite reaches the cystacanth stage. This layer is believed to be produced by the parasite.

5. The relevant literature is reviewed, and it appears that the envelopes surrounding all developing Acanthocephala, which have been studied to date, are probably capsules originating in the manner described above.

I am very grateful to Dr P. Tate for advice and encouragement during this work, and to Dr George Salt, F.R.S., for helpful discussions and criticism of the manuscript.
The biology of Pipunculus semifumosus (Kowarz) (Diptera: Pipunculidae), a parasite of Delphacididae (Homoptera), with observations on the effects of parasitism on the host
Authors: Rothschild G. H. L.
Published: June 2009

1. Pipunculus semifumosus (Kowarz) is an internal parasite of a number of common British Delphacidae. The life cycle and immature stages of the parasite are described.

2. The external and internal effects of parasitism on the delphacid host are described. Reductions in size and genital aberrations are related to the stage at which the host is attacked, and are most marked in female delphacids.
Reappraisal of the guinea-pig as an experimental host for studies of schistosomiasis mansoni
Authors: Pearce E. J. , McLaren Diane J.
Published: June 2009

The guinea-pig has been reassessed as a potential laboratory host forSchistosoma mansoni. Twenty-six per cent of an infective cercarial population survive to maturity in this rodent and there are no gross fluctuations in worm burden subsequent to pairing of male and female parasites. Five day, 4-week and 6-week-old schistosomes grown in guinea-pigs have topographical features that are identical to those exhibited by similarly aged mouse worms, but different from those exhibited by rat worms. Schistosome eggs are never detected in the faeces of infected guinea-pigs, but they can be observed in the pulmonary, hepatic and intestinal tissues. Only 55% of the eggs that can be recovered from the intestinal tissues are viable, and some of these can be hatched to release miracidia that penetrate the intermediate snail host. Cercariae are sometimes liberated from infected snails, but in insufficient numbers to permit infection of naive guinea-pigs. The schistosome cycle cannot, therefore, be completed in this host. Collaterals are sometimes observed in the vasculature serving the rectum and kidneys of infected guinea-pigs and the fact that schistosome eggs are deposited in the lungs of these animals indicates that portal systemic anastomosis is a feature of the model. Pathology associated with cercarial invasion or egg deposition is not dissimilar to that described for other laboratory animals infected withS. mansoni, except that basophils participate in the inflammatory response observed in the skin and intestine.
Temporal study of acquired resistance in infections of mice withGiardia muris
Authors: Belosevic M. , Faubert G. M.
Published: June 2009

Swiss CD-1 mice infected with cysts ofGiardia murisare protected against a challenge infection. A temporal study of this phenomenon was undertaken using two different approaches. First, the time needed for mice to acquire resistance was assessed by terminating the first infection using metronidazole on days 3, 6, 12, 24 or 48. These animals received a challenge infection 7 days later. Second, the duration of the protection was determined by giving mice a challenge infection on days 30, 60, 90, 120 or 150 after the primary infection. In all cases, a significant reduction in both cyst output and trophozoite numbers in the small intestine was observed after challenge. The reduction in cyst output following challenge was similar to the reduction in trophozoite numbers. The acquired resistance of some inbred strains of mice toG. muriswas similar to that of CD-1 Swiss mice. These results show that mice can acquire a significant resistance againstG. muriseven after a short period of contact with the parasite (3 days) and that the resistance may last up to 21 weeks.
Antigens of parasitic helminths in diagnosis, protection and pathology
Authors: Parkhouse R. M. E. , Harrison L. J. S.
Published: June 2009

A thorough study of parasitic helminth antigens is a pre-requisite for control programmes based on accurate immunochemical diagnosis, protection by vaccination and perhaps immune modulation to diminish pathological sequelae. Studies should be directed at the identification of those stage- or age-specific surface, secreted and somatic antigens which are involved in the host-parasite interactions responsible for immunity and/or pathology. Current methods of diagnosis of parasitic infections often fail to detect low-level patent infections, which incurs the risk of having a reservoir capable of perpetuating infections. There is, then, an urgent requirement for accurate immunochemical diagnosis, to be used in association with, and for the evaluation of, drug treatment and vector elimination, in parasite control programmes. Given the high sensitivity of current immunoassay technology, the only bar to establishing the necessary immunological tests is the choice of suitably specific antigen/antibody systems. Assays designed to detect parasite products or antigens are a major priority, as they indicate current infection, whereas those which detect antibody only indicate exposure to infection, which may or may not be current. Surface and secreted antigens are the most likely targets for protective immune responses and thus form a logical focus for vaccine design. The cestodes, which present such strong evidence for immunity following natural infection, are likely to yield effective vaccines by modern procedures. Certain antigens must, however, stimulate the humoral and/or cellular responses which are responsible for the undesirable immunopathological consequences of many helminthic diseases. The nematodes and trematodes furnish some extreme examples of such pathology. The ultimate objective in identifying these particular antigens is to utilize them in the appropriate down-regulation of the immune response responsible for such pathology. As an illustration, we have presented an interesting correlation between one particular clinical condition of onchocerciasis (Sowda) and the serological response, defined both in terms of the parasite antigens and an immunoglobulin class-restricted antibody response. Finally, the complexity of these parasite systems and the host response to the parasite should not be underestimated. Modern analytical techniques allow their detailed analysis in terms of the humoral antibody responses and afford the possibility of the future development of control and disease management procedures tailored to each individual host-parasite system. However, novel systems are required to complete the analysis of the cellular components of the immune response to parasite antigens, and functional studies are needed to determine the role that these parasite antigens play in the complex interaction between parasite and host.
The technique for breeding pure-line cultures of the blow-fly (Calliphora erythrocephala)
Authors: Tate P.
Published: June 2009

1. Pure-line breeding of Calliphora erythrocephala is difficult owing to the fact that gravïd females will oviposit at a distance from decomposing meat and the newly hatched larvae will crawl long distances and pass through minute openings to reach the food.

2. A simple and convenient cage for breeding blow-flies is described.

3. To obtain eggs free from contamination meat is plunged in boiling water before being put in the cages; and the vessel in which it is placed is sup ported on a glass cylinder standing in a dish of water.

4. The larvae are fed on horse-meat placed upon sawdust in a large watch-glass resting upon sawdust in a bowl. The bowl rests upon a support surrounded by water.

5. Pupation occurs in the sawdust beneath the watch-glass and puparia are separated from the sawdust by sieving.

6. Pupae are kept in glass dishes with closely fitting covers to prevent parasitism by Hymenoptera.

7. At a temperature of 21° C. the complete life cycle takes about 1 month.
The respiratory metabolism of parasitic nematodes
Authors: Rogers W. P.
Published: June 2009

1.Qo2values forHaemonchus contortusegs varied between − 9·7 and − 12·6 according to the degree of development of the embryos. The r.q. was in the region of 0·6.

2. Young infective larvae ofNippostrongylus murishad a highQo2(−18·4), which fell as the larvae aged. Third stageHaemonchus contortuslarvae gave similar results. The respiration was not affected by exsheathment.

3. Adult parasites gaveQo2values as follows:Ascaridia galli, − 2·5;Nematodirusspp., − 5·1;Nippostrongylus muris, − 6·8;Neoaplectana glaseri,− 12·6. When calculated on a surface area basis,Ascaridia gallihad an oxygen uptake which was much higher than that of the other organisms.

4. Qco2values were small. The r.q. of infective larvae, which contain fat as reserve material, was about 0·72. The other forms which contained much glycogen as well as fat had r.q. values between 0·6 and 0·7.A. galliwas an exception in that an r.q. of about 0·95 was obtained.

5. Potassium cyanide inhibited respiration in all the forms examined.

The author is indebted to Dr R. W. Glaser for supplying a strain ofNeoaplectana glaseri.
A new copepod parasite, Lernanthropus dussumieria n.sp., from the gills of a Madras fish
Authors: Gnanamuthu C. P.
Published: June 2009

Four specimens of this parasite were collected from the gills of about two dozen Dussumieria acuta, a fish which is of market value in Madras. Of the four specimens, two were female and two were male; no two were found in the same fish. Both the males were 1·5 mm. long, while the two females measured 2·6 and 2·5 mm. respectively.
Host-parasite relationship between the American Streblidae and the bats, with a new key to the American genera and a record of the Streblidae from Trinidad, British West Indies (Diptera)
Authors: Jobling B.
Published: June 2009

In 1945 I received a large collection of Streblidae from the late Prof. A. M. Adamson, of the Imperial College of Tropical Agriculture. This collection was made by a post-graduate student, Mr T. S. Jones, and Dr E. C. Humphries, in Trinidad. Later on Mr Jones sent me another three collections, which together with the first comprised three hundred and sixty specimens, the largest number of Streblidae which has ever been collected in America. In addition, I received seven specimens from Mr P. C. J. Brunet, of Keble College, Oxford, which were also collected in Trinidad. I take this opportunity to express my thanks to all these gentlemen, and especially to Mr Jones, who also supplied me with the list of the bats of Trinidad, and some useful information regarding their roosting habits. My thanks are also due to Dr T. C. S. Morrison-Scott and Mr R. W. Hayman of the British Museum (Natural History) for their help in checking the names of several species of bats. The present record is based on the abovementioned five collections and also includes all those records which had been known from Trinidad before.
Studies on the virus of turnip yellow mosaic
Authors: Markham Roy , Smith Kenneth M.
Published: June 2009

A new virus affecting cruciferous plants is described and the name suggested for it is theturnip yellow mosaic virus.The virus is sap-transmissible and has a dilution end-point in extracted sap of 10−5. The thermal inactivation point lies between 70 and 75° C.

The virus is not transmitted by insects with sucking mouthparts, but the insect vector in nature is a flea-beetle,Phyllotretasp. More than one species of flea-beetle can transmit the virus.

Under experimental conditions the virus has been transmitted by the mustard beetle,Phaedon cochleariaeand its larva; by the ‘long-horn’ grasshopper,Leptophyes punctatissimaBosc.; by the ‘short-horn’ grasshopper,Stauroderus bicolorCharp. and by the common earwig,Forflcula auriculariaLinn. Lepidopterous larvae have, so far, failed to transmit the virus.

The relationship of the virus with biting insects is discussed.

Turnip yellow mosaic virus has been obtained from several cruciferous plants as a nucleoprotein of the pentose type. It crystallizes from salt solutions as isotropic octahedra and from 20% alcohol at pH 3·7 as birefringent needles. On centrifuging out of solution the pellets are also crystalline. The virus preparation contains some 22% of nucleic acid.

The virus is denatured at room temperature in alcohol of concentration greater than 30% in neutral solutions, and the nucleic acid, which is a large polymerized particle, is liberated.

The preparations have been found to consist of 80 % of a nucleoprotein and 20 % of a nucleic acid-free protein which may be isolated by high-speed centrifuging. The latter has the same electrophoretic mobility and isoelectric point (pH 3·7) as the nucleoprotein; both crystallize in the same crystal form, and they are serologically identical.

The nucleic acid-free material does not seem to be infectious.
The effect of the parasitic copepod, Mytilicola intestinalis (Steuer) upon the condition of mussels
Authors: Cole H. A. , Savage R. E.
Published: June 2009

1. Mytilicola intestindlis (Steuer) was found in 100% of mussels examined from Blyth, Northumberland. These mussels varied in length between 3·5 and 7·5 cm.

2. The degree of infestation varied from two to fifty-nine parasites per mussel.

3. There was an inverse relationship between the condition of mussels of the size group 5·5–5·9 cm. and both the mean number of parasites per mussel and the mean number of parasites over 1·5 mm. in length per mussel.

4. The mean weight of flesh per mussel in the size group 5·5–5·9 cm. (shell length) was 3·206 g. from Blyth (parasitized) and 5·975 g. from Conway (not parasitized).

5. It is concluded that the presence of Mytilicola is associated with a serious reduction of condition in infested mussels.
Vallisiopsis contortan.g. and n.sp. andGastrocotyle indican.sp., monogenetic trematodes from marine fishes of the Madras coast
Authors: Subhapradha C. K.
Published: June 2009

Two new monogenetic trematodes of the sub-order Polyopisthocotylea Odhner were obtained from the gills of marine fishes. The characters of the first (Vallisiopsis contorta) agree with those of the subfamily Vallisiinae Price (family Discocotylidae Price) except in the presence of accessory sclerites in the clamp skeleton. As the mere presence of accessory sclerites does not justify the creation of a new subfamily, I refer this species to the subfamily Vallisiinae the diagnosis of which should, however, include the presence of accessory sclerites as an additional character. The second species described belongs to the subfamily Gastrocotylinae Sproston (family Microcotylidae Taschenberg).
Observations upon a trichomonad (Protozoa: Mastigophora) from the gut of the snake,Vipera ammodytesL.
Authors: Whittington M. Joan
Published: June 2009

1. The structure, method of division and cultural requirements of a trichomonad from the gut ofVipera ammodytesL. have been studied; the organism was found, in these respects, to be identical withTrichomonas batrachorumPerty, 1852.

2. Tadpoles ofBufo vulgarishave been infected experimentally with the strain.

3. It is concluded that the trichomonad was a strain ofTrichomonas batrachorumestablished in a reptilian host.
Occurrence of Globidium gilruthi, a protozoon parasite of sheep and goats, from the Indo-Pakistan sub-continent.
Authors: Sarwar M. M.
Published: June 2009

During the collection of helminths from a goat, millet-sized nodules were noticed in the mucous membrane of the abomasum. Examination of these nodules showed that there were no larval nematodes in their substance, but that they contained a large mass of spores. The nodules were identified as cysts belonging to the protozoon parasite, Globidium gilruthi. This parasite has not previously been recorded from the Indo-Pakistan sub-continent. The parasite was for the first time observed by Flesch (1883). Moussu & Marotel (1902) regarded it as a developmental stage of the coccidium, Eimeria faurei. It was studied by Gilruth (1910) and in the same year by Chatton (1910), who named it as Gastrocystis gilruthi.
The quantity and distribution of the ciliate Protozoa in the large intestine of the horse
Authors: Adam K. M. G.
Published: June 2009

1. A method is described for separating and enumerating the ciliate Protozoa which occur in the large intestine of the horse.

2. The concentration of ciliates varied in the different regions of the large intestine, being low in the caecum and highest in the left dorsal colon.

3. Two distinct populations of ciliates occurred in the large intestine of the horse, one from the caecum to the pelvic flexure and the other from the pelvic flexure to the rectum.
The occurrence in Pakistan of a humanEntamoeba of the poleckitype
Authors: Lubinsky George
Published: June 2009

1. The occurrence of cysts of thepoleckitype in an apparently healthy person in Pakistan is recorded.

2. The possible relationship of thepoleckitype cysts and theminutaform ofE. histolyticais discussed.
Human Nature, Personhood, and Ethical Naturalism
Authors: Hacker-Wright John
Published: June 2009

John McDowell has argued that for human needs to matter in practical deliberation, we must have already acquired the full range of character traits that are imparted by an ethical upbringing. Since our upbringings can diverge considerably, his argument makes trouble for any Aristotelian ethical naturalism that wants to support a single set of moral virtues. I argue here that there is a story to be told about the normal course of human life according to which it is no coincidence that there is agreement on the virtues. Because we are creatures who arrive at personhood only by learning from others in a relation of dependency, we cannot help but see ourselves as creatures for whom non-instrumental rationality is the norm. Those who train others in personhood must view the trainee's interests as having a value independent of their interests and must imbue the trainee with a sense of that value. Extending and preserving the sense of self-worth that we must acquire if we are to acquire personhood requires we see ourselves as creatures who need something like the virtues.
Caenorhabditis elegans utilizes dauer pheromone biosynthesis to dispose of toxic peroxisomal fatty acids for cellular homoeostasis
Authors: Joo Hyoe-Jin , Yim Yong-Hyeon , Jeong Pan-Young , Jin You-Xun , Lee Jeong-Eui , Kim Heekyeong , Jeong Seul-Ki , Chitwood David J. , Paik Young-Ki
Published: June 2009

Caenorhabditis elegans excretes a dauer pheromone or daumone composed of ascarylose and a fatty acid side chain, the perception of which enables worms to enter the dauer state for long-term survival in an adverse environment. During the course of elucidation of the daumone biosynthetic pathway in which DHS-28 and DAF-22 are involved in peroxisomal β-oxidation of VLCFAs (very long-chain fatty acids), we sought to investigate the physiological consequences of a deficiency in daumone biosynthesis in C. elegans. Our results revealed that two mutants, dhs-28(tm2581) and daf-22(ok693), lacked daumones and thus were dauer defective; this coincided with massive accumulation of fatty acyl-CoAs (up to 100-fold) inside worm bodies compared with levels in wild-type N2 worms. Furthermore, the deficiency in daumone biosynthesis and the massive accumulation of fatty acids and their acyl-CoAs caused severe developmental defects with reduced life spans (up to 30%), suggesting that daumone biosynthesis is be an essential part of C. elegans homoeostasis, affecting survival and maintenance of optimal physiological conditions by metabolizing some of the toxic non-permissible peroxisomal VLCFAs from the worm body in the form of readily excretable daumones.
Don't Stand So Close to Me: The Effect of Auditory Input on Interpersonal Space
Authors: Lloyd Donna M , Coates Anna , Knopp Jasmin , Oram Sarah , Rowbotham Samantha
Published: June 2009

We provide preliminary evidence that listening to music through headphones alters the perception of space around the body—specifically, the interpersonal distance maintained between the self and others. In comparison to an external auditory environment, wearing headphones or earplugs increased the amount of space maintained between the wearer and another person during an active approach paradigm. This finding suggests that, when external cues to spatial location (such as sound) are removed, people compensate by increasing the distance between themselves and others. The implications of this research for navigating busy urban environments and for the social interactions of wearers of personal music systems are discussed.
PROCAIN server for remote protein sequence similarity search
Authors: Wang Yong , Sadreyev Ruslan I. , Grishin Nick V.
Published: June 2009

Sensitive and accurate detection of distant protein homology is essential for the studies of protein structure, function and evolution. We recently developed PROCAIN, a method that is based on sequence profile comparison and involves the analysis of four signals—similarities of residue content at the profile positions combined with three types of assisting information: sequence motifs, residue conservation and predicted secondary structure. Here we present the PROCAIN web server that allows the user to submit a query sequence or multiple sequence alignment and perform the search in a profile database of choice. The output is structured similar to that of BLAST, with the list of detected homologs sorted by E-value and followed by profile–profile alignments. The front page allows the user to adjust multiple options of input processing and output formatting, as well as search settings, including the relative weights assigned to the three types of assisting information.

Availability:  http://prodata.swmed.edu/procain/

Contact:  grishin@chop.swmed.edu
Species identification of Anguilla japonica by real-time PCR based on a sequence detection system: a practical application to eggs and larvae
Authors: Minegishi Yuki , Yoshinaga Tatsuki , Aoyama Jun , Tsukamoto Katsumi
Published: June 2009

Minegishi, Y., Yoshinaga, T., Aoyama, J., and Tsukamoto, K. 2009. Species identification of Anguilla japonica by real-time PCR based on a sequence detection system: a practical application to eggs and larvae. – ICES Journal of Marine Science, 66: 1915–1918. To develop a practical method for identifying Japanese eel Anguilla japonica eggs and larvae to species by a sequence detection system using a real-time polymerase chain reaction (PCR), we examined (i) the sensitivity of the system using samples at various developmental stages, and (ii) influences of intra- and interspecific DNA sequence variations in the PCR target region. PCR amplifications with extracted DNA solution at 7.0 ng µl−1 or lower were efficient at distinguishing A. japonica from other anguillids. A single egg at the gastrula or later developmental stages could also be identified. Two sequence variations in the PCR target region were observed in 2 out of 35 A. japonica collected from three localities, and from four year classes at a single locality. These mutations, however, did not affect the result of species identification achieved by A. japonica-specific PCR primers and probe. The accuracy of this PCR-based method of species identification will help in field surveys of the species.
Fractal solids, product measures and fractional wave equations
Authors: Li Jun , Ostoja-Starzewski Martin
Published: June 2009

This paper builds on the recently begun extension of continuum thermomechanics to fractal porous media that are specified by a mass (or spatial) fractal dimension
D
, a surface fractal dimension
d
and a resolution length scale
R
. The focus is on pre-fractal media (i.e. those with lower and upper cut-offs) through a theory based on a dimensional regularization, in which
D
is also the order of fractional integrals employed to state global balance laws. In effect, the governing equations are cast in forms involving conventional (integer order) integrals, while the local forms are expressed through partial differential equations with derivatives of integer order but containing coefficients involving
D
,
d
and
R
. This procedure allows a specification of a geometry configuration of continua by ‘fractal metric’ coefficients, on which the continuum mechanics is subsequently constructed. While all the derived relations depend explicitly on
D
,
d
and
R
, upon setting
D
=3 and
d
=2, they reduce to conventional forms of governing equations for continuous media with Euclidean geometries. Whereas the original formulation was based on a Riesz measure—and thus more suited to isotropic media—the new model is based on a product measure, making it capable of grasping local fractal anisotropy. Finally, the one-, two- and three-dimensional wave equations are developed, showing that the continuum mechanics approach is consistent with that obtained via variational energy principles.
Expression of two xylanase genes from the rumen cellulolytic bacterium Ruminococcus flavefaciens 17 cloned in pUC13
Authors: Flint Harry J. , McPherson Carol A. , Martin Jennifer
Published: June 2009

Two distinct xylanase genes (designated xynA and xynB) were subcloned in pUC13 from non-homologous restriction fragments of Ruminococcus flavefaciens 17 DNA originally isolated in λ EMBL3. The products of the two genes showed similar pH optima for hydrolysis of oat spelt xylan (around 5·5) and had little or no activity against carboxymethylcellulose. Trace activities against p-nitrophenyl (pNP) cellobioside and pNP-xyloside were detected in clones containing xynA, but not in one harbouring xynB. The xylanase associated with clones carrying xynA produced mainly xylobiose and xylose from xylan and did not give hydrolysis of xylobiose, while that encoded by xynB produced mainly xylobiose and higher xylo-oligosaccharides from xylan. There was evidence of increased expression, at the RNA level, of these two genes, and of another cloned region encoding multiple activities including xylanase, in R. flavefaciens 17 grown with xylan, as compared with cellobiose, as energy source. Total cell-associated xylanase and β-xylosidase activities, and supernatant xylanase activity, were shown to be similarly induced in xylan-grown R. flavefaciens, 17.
Cloning of chromosomal β-lactamase genes from Yersinia enterocolitica
Authors: Seoane Asunción , Lobo Juan M. García
Published: June 2009

Summary: Two β-lactamase genes present in the chromosome of Yersinia enterocolitica have been cloned individually into the plasmid pACY184 and expressed in Escherichia coli. The gene for broad-spectrum β-lactamase I (‘A’) was cloned from a strain belonging to the O:3 serotype, and the gene for (cephalosporinase) β-lactomase II (‘B’) was cloned from a strain of the O:5b serotype. The properties of the β-lactamases expressed in E. coli are similar to those previously described in Y. enterocolitica.
Directed evolution of amidase in Methylophilus methylotrophus; purification and properties of amidases from wild-type and mutant strains
Authors: Silman Nigel J. , Carver Mark A. , Jones Colin W.
Published: June 2009

The obligately methylotrophic bacterium Methylophilusmethylotrophus hydrolyses acetamide and acrylamide using a cytoplasmic amidase. In previous work, continuous culture was used to isolate spontaneous mutants which overexpressed either the wild-type amidase (strain MM6) or a mutant amidase with an apparently higher K
cat (strain MM8). We now report that NTG mutagenesis of strain MM8 followed by acrylamide-limited growth at low dilution rate (D 0·025 h-1; 37 °C) led to the selection of a strain which continued to overexpress the amidase, but which exhibited an unexpectedly low amidase activity and a greatly decreased K
m for acrylamide (strain MM15). Amidases from the wild-type and mutant strains were purified and shown to be homotetramers (subunit M
r 38000, pI 4·1). The N-terminal amino acid sequence of the wild-type enzyme was 90% homologous with the aliphatic amidase from Pseudomonas aeruginosa, and Southern blotting using an oligonucleotide probe for this region showed that overexpression of the enzyme in the mutant strains was not due to gene amplification. Compared with the wild-type and MM6 enzymes, the MM8 enzyme exhibited a threefold higher K
m and a slightly lower K
m for acrylamide, whereas the MM15 enzyme exhibited a similar K
cat and an eightfold lower K
m for acrylamide. The MM15 enzyme also reacted more extensively with the thiol group reagent DTNB, had a significantly lower sedimentation coefficient and exhibited a more relaxed substrate specificity, all of which were compatible with a looser tetrameric structure. It was also much more susceptible than the other three enzymes to inactivation by high temperature or by freezing and thawing (MM15»MM8>MM6/wild-type), both of which variably dissociated the enzyme into inactive dimers and monomers. The amidase activity of strain MM15 was almost 15-fold higher following growth at 25 °C than at 37 °C, since at this lower temperature the enzyme exhibited a similar K
cat to the MM8 enzyme and was not significantly dissociated. However, as strain MM15 readily outgrew the organism from which it was derived (strain MM8) during acrylamide-limited continuous culture at 37 °C, it is clear that under these conditions a low K
m was a greater selective advantage than a high K
cat.
Nitrogen fixation by Oscillatoria spp. under autotrophic and photoheterotrophic conditions
Authors: Gallon John R. , Hashem M. Abul , Chaplin Alan E.
Published: June 2009

Summary: Oscillatoria spp. UCSB8 and UCSB25 are both capable of aerobic N2 fixation. The optimum temperature for C2H2 reduction was 22 °C for Oscillatoria sp. UCSB8 and 35 °C for Oscillatoria sp. UCSB25, whilst the optimum temperature for growth on N2 was 25 °C and 30 °C, respectively. In Oscillatoria sp. UCSB25, but not in UCSB8, inhibition of N2 fixation may limit diazotrophic growth at temperatures above 35 °C. When grown under alternating 12 h light and 12 h darkness, both isolates reduced C2H2 predominantly in the dark and both were capable of N2 fixation and photoheterotrophic growth in the presence of 20 μm-DCMU to inhibit photosystem II activity. Under these conditions, the best exogenous carbon source for Oscillatoria sp. UCSB8 was glucose, whilst that for Oscillatoria sp. UCSB25 was fructose. In Oscillatoria sp. UCSB8, exogenous glucose was catabolized mainly through the oxidative pentose phosphate pathway. Although cultures grown photoheterotrophically showed higher specific activities of nitrogenase than photoautotrophic cultures, they grew more slowly. Furthermore, cultures grown photoheterotrophically under alternating light and darkness reduced C2H2 both in the light and in the dark, but the highest rates of C2H2 reduction were observed in the dark. This cyclic pattern of N2 fixation was independent of photosystem II activity.
Cloning and characterization of the ColE7 plasmid
Authors: Chak Kin-F. , Kuo White-S. , Lu fong-m , James R.
Published: June 2009

Summary: The 2·6 kb ColE7-K317 plasmid was mapped and the DNA fragments of the colicin E7 operon subcloned into pUC18 and pUC19. The size of the functional colicin E7 operon deduced by subcloning was 2·3 kb. The colicin E7 gene product was purified by carboxymethylcellulose chromatography. Both colicin E7 and E9 were demonstrated to exhibit a non-specific DNAase-type activity by in vitro biological assay. The molecular mass of colicin E7 was 61 kDa, as determined by SDS-PAGE. From DNA sequence data, the estimated sizes of the E7 immunity protein and the E7 lysis protein were 9926 Da and 4847 Da, respectively. Comparison of restriction maps and DNA sequence data suggests that ColE7 and ColE2 are more closely related than other E colicin plasmids.