bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors influencing infections in Rhipicephalus appendiculatus ticks fed on cattle infected with Theileria parva
Authors: Young A. S. , Dolan T. T. , Morzaria S. P. , Mwakima F. N. , Norval R. A. I. , Scott J. , Sherriff A. , Gettinby G. 
Published: June 2009

SUMMARYA large database on the transmission of a stabilate of the Theileria parva Muguga stock from one breed of cattle using two stocks of Rhipicephalus appendiculatus, Muguga and Ol Pejeta was developed and analysed. Factors associated with the ticks and cattle, and the infections developing in cattle were studied in relation to the infection variables in the tick batches harvested daily from cattle. Generalized Linear Interactive Modelling (GLIM) was used to determine the importance of factors and interactions in influencing the levels of tick infection variables using Type I and Type III sums of squares analyses. Analysis of the 6 variables, prevalence (percentage of ticks infected), abundance (mean number of infected salivary gland acini per tick examined) and intensity (mean number of infected salivary gland acini per infected tick) in batches of 30 male and 30 female ticks showed that 24 covariates, factors or interactions had a significant effect (P> 0·05). Certain covariates and factors were particularly important for all 6 tick infection variables; parasitaemia of animal on the day of tick harvest, stabilate dilution administered to animal, month in which tick batch was harvested, minimum packed cell volume of animal over the sampling period, age of animal, and the minimum leukocyte count of the animal over the sampling period. The GLIM analyses were found to be a useful tool in identifying factors that influence infection levels and in devising methods of producing tick batches with more predictable infections.
Transmission of histomoniasis with male Heterakis gallinarum (Nematoda)
Authors: Springer W. T. , Johnson Joyce , Reid W. M. 
Published: June 2009

Histomoniasis was transmitted to poults inoculated orally with recently harvested whole intact male worms in three trials (4/5, 5/6, 2/4), but not with female worms (0/5, 0/9, 0/3). When triturated male worms were given in two trials, the rate of transmission was reduced (3/5, 0/10). Triturated female worms given orally produced histomoniasis in 1/9 poults. These results suggest that further unknown steps may be involved in histomonad transmission by heterakid worms.This study was partially supported by NSF Grant GB-5227.
The morphology and life cycle ofProtopolystoma xenopi(Price) Bychovsky in Uganda
Authors: Thurston June P. 
Published: June 2009

1.The morphology ofProtopolystoma xenopifrom Uganda is compared with specimens previously described by Williams. The chief differences are the slightly greater maximum size, the presence of a second pair of anchors on the opisthaptor, and the absence of a second large oviducal chamber in the uterus.2. Encapsulation of the egg is described from living worms. A thin, plastic membrane forms around the ovum and yolk cells within the ootype before all the yolk cells have passed into the ootype. The remaining yolk cells pass from the ovo-vitelline duct into the sac formed by this membrane, which is attached to the distal walls of the ootype.3. Eggs are produced at the rate of 4–15 eggs/worm/24 hr. They hatch in 24–27 days at 24–26° C. The opisthaptor of the larva bears sixteen hooklets and two pairs of anchors, which are in the same positions as in the adult.4. One larva with one pair of suckers was obtained from the alimentary canal or kidney of a metamorphosingXenopustadpole. About sixty other tadpoles were examined forP. xenopibut none was found.5. TwelveP. xenopiwere recovered from the kidneys of a small frog that had been infected experimentally 10 days previously.6. When naturally infected small frogs from Kajansi Fish Farm were examined, immatureP. xenopiwere found in the kidney of one frog, in the urinary ducts of two frogs, and in the bladder of one frog. The infection rate was much lower than that in matureXenopus. ImmatureP. xenopiwere also found in the kidneys of matureXenopus mülleri.7.P. xenopimatures more rapidly than its host. A frog weighing only 2·9 g. contained a nearly mature worm in the bladder, while one weighing 4·2 g. contained two mature worms, shedding eggs. Eggs are shed throughout the year. The life cycle ofP. xenopiis therefore not regulated by that of its host.
Properties of red cell ghost preparations susceptible to invasion by malaria parasites
Authors: Dluzewski A. R. , Rangachari K. , Wilson R. J. M. , Gratzer W. B. 
Published: June 2009

SummaryExperimental procedures are described that lead to the formation of sealed red cell ghosts capable of efficient invasion by malaria parasites. Both human and monkey cells have been studied with respect to invasion byPlasmodium falciparumandP. knowlesirespectively. Resealed ghosts containing about half the normal concentration of haemoglobin are prepared by osmotic lysis and resealing at a haematocrit of 70%. When examined in the scanning electron microscope, populations of these ghosts contain few echinocytes, but have an abundance of stomatocytic forms. When undiluted haemolysate is substituted for the aqueous saline diluent, in which the cells are suspended for lysis and resealing, discocytes result, with a morphology very similar to that of the original cells. Invasion is somewhat, but not dramatically higher for this material. An investigation of the effect of intracellular potassium concentration revealed that this had no major effect on invasion. A small increase in invasion resulted from addition of 50 or 100 mg/ml of albumin to the medium in which the cells were resealed, but intra-erythrocytic protein contentper seis evidently not a major factor in determining the efficiency of invasion. Augmentation of the cytoplasmic ATP concentration during lysis and resealing increased the level of parasitaemia significantly, and the parasites in these ghosts developed normally and gave rise to viable merozoites. It was found that albumin at certain concentrations passed freely into the lysed cells and reached equilibrium with that in the external medium. By contrast, the high molecular weight solute Blue Dextran 2000 was completely excluded from the lysed cells.
Nature and nurture: overcoming constraints on immunity
Authors: Wakelin D. 
Published: June 2009

SUMMARYParasitic infections in man and domestic animals exhibit two striking characteristics (a) their prevalence is high, but infections are unequally distributed among individuals within populations and (b) immunity is often slow to develop and appears, at best, only partially effective. Recent immunological and epidemiological studies suggest that effective immunity can develop, but that high prevalence within populations reflects the operation, not only of socio-economic and climatic factors, or husbandry practices, but also of powerful environmentally induced constraints upon the development of resistance. Immunogenetic studies suggest the operation of additional constraints which reflect individual genetic characteristics, and which influence the ability to develop and express effective immunity. A full understanding of all constraints is necessary before levels of population and individual resistance to infection can be increased; the need for such understanding has become more pressing with the prospect that anti-parasite vaccines may become available. Two aspects of environmentally induced constraints are considered, those arising from nutritional inadequacies and those resulting from exposure to infection in early life. Both are discussed primarily in terms of helminth parasites. Genetically determined constraints are discussed with reference to MHC-restricted recognition of malarial peptide vaccines and in terms of Class II molecule-directed control of T-cell function inLeishmaniainfections. Genetic influences are also considered from the standpoint of inflammatory cell function, in immunity against intestinal nematodes and in vaccine-induced immunity againstSchistosoma. Finally, parasite-induced constraints, particularly those which down-regulate protective responses are discussed briefly.
The ecology of immature phases of trichostrongyle nematodes
Authors: Crofton H. D. 
Published: June 2009

Observations on the larvae of sheep trichostrongyles on hill pastures showed:1. A reduction in larval populations occurred when the ‘moving-flock’ type management was used. The large proportion of eggs passed in faeces is deposited on a part of the pasture where little or no grazing occurs.2. Local concentrations of larvae occurred on the grazed portions of a pasture when grazing was uneven. Thus, the apparent low rate of stocking on hill pastures does not give a true picture of the potential dangers of parasitic disease. Estimates of pasture contamination by Taylor's method of sampling were deceptively low.3. The number of larvae on grass blades was lowest when the grass was wet with dew. Sampling of pastures between 12 noon and 5 p.m g.m.t. gave maximal and most constant estimates.4. There was an increase in the number of larvae on a pasture during the warmer months of the year. While low temperatures prevent or delay hatching, the increase in population was not entirely due to the increased rate of development when temperature was high. The increase in numbers was partly due to an increase in the number of adult worms in the sheep hosts.5. Removal of sheep for 3 weeks reduced the number of larvae on a pasture. This reduction was not apparent, however, until after the first 12 days. After 3 weeks the pasture population was reduced by 55 %, while after 4 weeks (i.e. 7 days after the return of the sheep) the reduction was 90%. Two weeks later there was a small increase in the larval population, but this was again reduced with the onset of colder conditions.
Pamaquin Resistance in a Strain of Plasmodium gallinaceum and its relationship to Other antimalarial Drugs
Authors: Bishop Ann , McConnachie Elspeth W. 
Published: June 2009

1. A four- to eight-fold increase in resistance to pamaquin has been developed in a strain of Plasmodium gallinaceum in chicks.2. Pamaquin resistance conferred no resistance to proguanil, sulphadiazine, mepacrine, chloroquine or sontochin, but it conferred some resistance to pentaquine and to quinine.3. An appreciable loss in resistance to pamaquin was observed in the pamaquin-resistant strain after it had been maintained in the absence of the drug, in a patent state of infection, for a period of 6 months.4. No synergism was observed between pamaquin and quinine when these drugs were tested, in combined doses, upon active infections of P. gallinaceum.
The capitulum and feeding mechanism ofIxodes hexagonusLeach. II
Authors: Arthur D. R. 
Published: June 2009

1. The action of the mouthparts ofIxodes hexagonusduring the penetration of artificial membranes is described.2. Above the hypostomal groove, the chelicerae are closely apposed in the mid-line, but on the inner lower surface each inner cheliceral sheath is drawn into a ventral, toothed lobe, which overlies the hypostomal groove. This lobe disappears in front of the labro-hypostomal groove.3. A lamellate mass of homogeneous material surrounds the rostrum in the skin and at the tip of the hypostome there is marked cytolysis of the dermal cells. There are some pyknotic nuclei visible in this region, and the endothelial walls of the capillaries are swollen, and some contain many polymorphs.
The development of resistance to metachloridine inPlasmodium gallinaceumin Chicks
Authors: Bishop Ann , McConnachie Elspeth W. 
Published: June 2009

1. An increase in resistance to metachloridine of more than 100-fold was obtained within a few weeks in a strain ofPlasmodium gallinaceumtreated with gradually increasing doses of the drug and maintained in young chicks by blood-inoculation at intervals of 2–3 days.2. There was no evidence that the rapid development of resistance arose by the selection of highly resistant individuals present in the normal population.3. Two strains ofP. gallinaceumpassaged through chicks treated with 0·025 mg. doses of the drug gradually became resistant to greater concentrations than that to which they had been exposed, though their growth rate decreased when they were inoculated into birds receiving higher doses of the drug.4. In both strains maintained in birds treated with 0·025 mg. doses of the drug, resistance reached a maximum beyond which it did not increase.5. Cross-resistance tests failed to show any relationship in mode of action between meta-chloridine and pamaquin, mepacrine, quinine or chloroquine. A strain ofP. gallinaceum, highly resistant to metachloridine, showed slight resistance to sulphadiazine, sulphapyridine and sulphathiazole, but none to sulphanilamide or proguanil.We are indebted to the Cyanamid Products Ltd., London, for the gift of the Folvite used in these experiments.
Acquisition of iron from host sources by mesophilic Aeromonas species
Authors: Massad George , Arceneaux Jean E. L. , Byers B. Rowe 
Published: June 2009

Summary
The mesophilic Aeromonas species are opportunistic pathogens that produce either of the siderophores amonabactin or enterobactin. Acquisition of iron for growth from Fe-transferrin in serum was dependent on the siderophore amonabactin; 50 of 54 amonabactin-producing isolates grew in heat-inactivated serum, whereas none of 30 enterobactin-producing strains were able to grow. Most isolates (regardless of siderophore produced) used haem as a sole source of iron for growth; all of 33 isolates grew with either haematin or haemoglobin and 30 of these used haemoglobin when complexed to human haptoglobin. Mutants unable to synthesize a siderophore used iron from haem, suggesting that this capacity was unrelated to siderophore production. Some members of the mesophilic Aeromonas species have evolved both siderophore-dependent and -independent mechanisms for acquisition of iron from a host.
Regulation of protein phosphorylation in the cyanobacterium Anabaena strain PCC 7120
Authors: Mann Nicholas H. , Rippka Rosmarie , Herdman Michael 
Published: June 2009

Summary
Protein kinase activities have been detected in cell-free extracts of the cyanobacterium Anabaena PCC 7120. At least 12 polypeptides in the soluble fraction were phosphorylated in vitro at the expense of [γ
-32P]ATP and the pattern of phosphorylation was shown to be regulated by intermediary metabolites and other effectors, at physiological concentrations. Glucose 6-phosphate exerted a regulatory effect on a phosphopolypeptide of M
r 56000 (p56) by stimulating a protein phosphatase, whereas ribulose 5-phosphate inhibited the corresponding protein kinase. In addition, DTT and the calmodulin antagonist trifluoperazine influenced the phosphorylation state of several different polypeptides, indicative of control by redox conditions and a calmodulin-like mediator, respectively. Furthermore, it was established that the phosphorylation of p56 required Mg2+ (> 100 μM) whereas that of a polypeptide of M
r 16000 occurred in the absence of Mg2+ and was inhibited by high concentrations (> 1 mm) of this cation. Several of the phosphopolypeptides detected in vitro corresponded in mobility on SDS-PAGE to species phosphorylated in vivo.
Characterization of the periplasmic cytochromes c of Paracoccus denitrificans: identification of the electron acceptor for methanol dehydrogenase, and description of a novel cytochrome c heterodimer
Authors: Long Anthony R. , Anthony Christopher 
Published: June 2009

Summary
This paper describes periplasmic c-type cytochromes from two strains of Paracoccus denitrificans NCIB 8944 grown in heterotrophic or methylotrophic conditions. It is shown that the functions of two monomeric, monohaem cytochromes induced during growth on methanol have been wrongly designated in previous work. The CO-reactive cytochrome c
553 (30 kDa) is not the electron acceptor for methanol dehydrogenase; this is shown to be the role of the cytochrome c
552 (22 kDa). The monomeric 45 kDa cytochrome induced in conditions of oxygen insufficiency is a dihaem c-type cytochrome and does not contain haem b as previously assumed. In addition to these cytochromes, the Oxford strain of NCIB 8944 contains two cytochrome c complexes. One of these (150 kDa), produced in relatively small amounts, consists of a non-haem protein plus four haemoproteins (28, 33, 41 and 47 kDa). The second complex is a novel dimeric multi-haem cytochrome c (46 kDa) which constitutes about 25% of the periplasmic c-type cytochrome. It reacts with CO and has no methionine ligands. One subunit (16 kDa) has two low-spin haems; the larger subunit (30 kDa) has three haems which have low-spin characteristics in the oxidized state and are high-spin in the reduced state. The subunits were readily separated at pH 12 and could be subsequently reconstituted into a complex indistinguishable from the original. The 30 kDa subunit was denatured on prolonged exposure to high pH, which also converted it to a low-spin cytochrome. No function could be designated for these novel c-type cytochrome complexes.
Cellular fatty acyl and alkenyl residues in Megasphaera and Pectinatus species: contrasting profiles and detection of beer spoilage
Authors: Helander Ilkka M. , Haikara Auli 
Published: June 2009

SUMMARY
The strictly anaerobic Gram-negative beer spoilage bacteria Megasphaera cerevisiae, Pectinatus cerevisiiphilus and P. frisingensis were subjected to cellular fatty acid analysis, employing acid- and base-catalysed cleavage, gas chromatography and mass spectrometry. M. cerevisiae contained 12:0, 16:0, 16:1, 18:1, 17:cyc, 19:cyc, 12:0(3OH), 14:0(3OH) as the main fatty acids, and alk-1-enyl chains instead of acyl chains were detected to a considerable extent (14% of total fatty acids), indicating the presence of plasmalogens. The fatty acid pattern of M. cerevisiae was almost identical to that of M. elsdenii, the only species previously assigned to this genus. P. cerevisiiphilus and P. frisingensis yielded fatty acids that were heavily dominated by odd-numbered chains; 11:0, 15:0, 17:1, 18:cyc and 13:0(3OH) were the main fatty acids detected in both species. Alk-1-enyl chains with similar chain lengths were also found. Both Pectinatus species contained six different 3-hydroxy fatty acids with chain lengths between 11 and 15 carbons, 13:0(3OH) being dominant and the others accounting for generally less than 1% of total fatty acids. Among the minor components, an unsaturated 3-hydroxy fatty acid was detected which was shown to be 13:1(30H). In addition, fatty acid analysis was shown to be applicable to detection of bacterial contamination of beer.
Cloning of a Candida albicans peptide transport gene
Authors: Basrai Munira A. , Lubkowitz Mark A. , Perry Jack R. , Miller David , Krainer Eduardo , Naider Fred , Becker Jeffrey M. 
Published: June 2009

SUMMARY
A Candida albicans peptide transport gene, CaPTR2, was cloned from a C. albicans genomic library by functional complementation of a peptide transport deficient mutant (strain ptr2-2) of Saccharomyces cerevisiae. CaPTR2 restored peptide transport to transformants as determined by uptake of radiolabelled dileucine, growth on dipeptides as sources of required amino acids, and restoration of growth inhibition by toxic peptides. Plasmid curing experiments demonstrated that the peptide transport phenotype was plasmid borne. CaPTR2 was localized to chromosome R of C. albicans by contour-clamped homologous electric field gel chromosome blots. Deletion subclones and frameshift mutagenesis were used to narrow the peptide transport complementing region to a 5:1 kb DNA fragment. DNA sequencing of the complementing region identified an ORF of 1869 bp containing an 84 nucleotide intron. The deduced amino acid sequence predicts a protein of 70 kDa consisting of 623 amino acids with 12 hydrophobic segments. A high level of identity was found between the predicted protein and peptide transport proteins of S. cerevisiae and Arabidopsis thaliana. This study represents the first steps in the genetic characterization of peptide transport in C. albicans and initiates a molecular approach for the study of drug delivery against this pathogen.
Improved therapeutic efficacy against murine carcinoma by combining honokiol with gene therapy of PNAS‐4, a novel pro‐apoptotic gene
Authors: Yuan Zhu , Liu Huanyi , Yan Fei , Wang Yongsheng , Gou Lantu , Nie Chunlai , Ding Zhenyu , Lai Songtao , Zhao Yuwei , Zhao Xinyu , Li Jiong , Deng Hongxin , Mao Yongqiu , Chen Lijuan , Wei Yuquan , Zhao Xia 
Published: June 2009

PNAS‐4, a novel pro‐apoptotic gene activated during the early response to DNA damage, can inhibit proliferation via apoptosis when overexpressed in some tumor cells. Recent studies have indicated that honokiol can induce apoptosis, inhibit angiogenesis, and suppress tumor growth. In the present study, we investigated whether mouse PNAS‐4 (mPNAS‐4) could augment the apoptosis of tumor cells induced by honokiol in vitro, and whether the antiangiogenic activity of honokiol and induction of apoptosis by mPNAS‐4 could work cooperatively to improve the antitumor efficacy in vivo. In vitro, mPNAS‐4 inhibited proliferation of murine colorectal carcinoma CT26 and Lewis lung carcinoma LL2 cells through induction of apoptosis, and significantly augmented the apoptosis of CT26 and LL2 cells induced by honokiol. Compared with treatment with mPNAS‐4 or honokiol alone, in vivo systemic administration of an expression plasmid encoding mPNAS‐4 and low‐dose honokiol significantly suppressed tumor growth through the enhanced induction of apoptosis and the augmented inhibition of angiogenesis. Our data suggest that the combined treatment with mPNAS‐4 plus honokiol augments antitumor effects in vitro and in vivo, and that the improved antitumor activity in vivo may be associated with enhanced induction of apoptosis and augmented inhibition of angiogenesis. The present study may provide a novel and effective method for the treatment of cancer. (Cancer Sci 2009; 100: 1757–1766)
Spike‐monitoring of anaesthesia for corpus callosotomy using bilateral bispectral index
Authors: Ogawa S. , Okutani R. , Nakada K. , Suehiro K. , Shigemoto T. 
Published: June 2009

SummaryDuring corpus callosotomy for intractable epilepsy, the electrocorticogram is commonly recorded from electrodes placed on the brain surface to monitor of epileptic activity and assess the synchronisation of epileptic signals between the left and the right hemispheres. We evaluated the usefulness of bilateral bispectral index monitoring using two monitors and two sensors placed above the frontal region. Spikes were readily detected on the electroencephalogram on the bispectral index monitor, and the frequency of their occurrence increased or decreased in response to adjustment of the sevoflurane concentration. The disappearance of synchronisation between the left and the right hemispheres was observed with use of the bispectral index – in concordance with the electrocorticogram. Thus, ‘spike‐monitoring anaesthesia’ using bilateral bispectral index was useful in assessing both the effect of anaesthetics on the electroencephalogram signals and the surgical therapeutic effect.