Strain specific immunity to Plasmodium berghei: a new genetic marker

Parasitology ◽  
1973 ◽  
Vol 67 (1) ◽  
pp. 17-27 ◽  
Author(s):  
A. I. Oxbrow

Mice immunized by single pyrimethamine terminated infections of Plasmodium berghei berghei, strain NK65 or the Nigerian P. berghei-like parasite, N67, were immune to challenge by P.b. berghei, P.b. yoelii strain 17X, P.b. killicki strain 194ZZ and N67. Mice similarly immunized against P.b. yoelii were only immune or N67 resulted in infections comparable to those found in normal mice. Mice immunized against P.b. killicki were similar except that they also possessed some protection against challenge by N67. Evidence was obtained which indicated that the difference between P.b. yoelii and N67 was not associated with the virulence of the parasites. Prolonged exposure to P.b. yoelii infection slightly increased homologous and heterologous immunity. Two lines of parasites were crossed; one of these was derived from P.b. yoelii and the other from N67. They differed in pyrimethamine sensitivity, glucose phosphate isomerase type and the ability to survive in mice immunized against P.b. yoelii. Ten lines of parasites showing the P.b. yoelii characters of pyrimethamine resistance and GPI-1 were isolated in drug treated mice immune to P.b. yoelii challenge. Twenty-one clones were isolated without drug or antibody selection from the parasites resulting from the cross between P.b. yoelii and N67. Sixteen of these clones were classified according to the markers which they possessed and six were found to be recombinant in character. The experiments showed that genetic recombination occurred as a frequent event in P. berghei and involved factors which control the cross-immunity produced following infection with these parasites.

Parasitology ◽  
1973 ◽  
Vol 66 (2) ◽  
pp. 309-320 ◽  
Author(s):  
D. Walliker ◽  
R. Carter ◽  
S. Morgan

Crosses have been made between two lines of Plasmodium berghei yoelii differing in drug-sensitivity and enzyme-type. The two lines used were line A, which is pyrimethamine-resistant and contains an electrophoretic form of glucose phosphate isomerase termed GPI-1, and line C, which is pyrimethamine-sensitive and contains enzyme-form GPI-2. Equal numbers of blood forms of lines A and C were mixed and injected intravenously into a mouse. Mosquitoes were fed immediately on the mixture, and the resulting sporozoites used to infect further rodents. After treating these animals with pyrimethamine, drug-resistant parasites characterized by GPI-2 could be detected in the remaining infections. Controls showed that these parasites were recombinant forms, which had arisen by cross-fertilization of gametes in the mosquitoes, and not by mutation or ‘synpholia’. By cloning the products of crosses between lines A and C by dilution, parasite lines of two recombinant classes (resistant GPI-2 and. sensitive GPI-1) were isolated, together with lines of parental characteristics.


1984 ◽  
Vol 44 (2) ◽  
pp. 169-181 ◽  
Author(s):  
John D. West ◽  
Graham Fisher

The dimeric enzyme glucose phosphate isomerase (GPI-1) is regulated in oocytes by a cis-acting temporal gene (Gpi-1t) that maps close to the structural gene (Gpi-1s). Quantitative cellulose acetate electrophoresis of GPI-1 allozymes from unfertilized eggs produced by various Gpi-1sa / Gpi-1sb heterozygous females revealed a new Gpi-1t allele that we have designated Gpi-1tc. This allele is present in 101/H mice and a partially congenie stock that carries the Gpi-lsa gene derived from the AKR strain. We have confirmed that Gpi-1tc is closely linked to Gpi-1s and that it is cis-acting. It produces higher levels of GPI-1 in unfertilized eggs than the other two Gpi-lt alleles that are known (Gpi-1ta and Gpi-1tb) but has no effect on GPI-1 in somatic tissues or spermatozoa. This new Gpi-1t allele represents a third developmental programme for GPI-1 expression in oocytes.


1980 ◽  
Vol 59 (6) ◽  
pp. 411-421 ◽  
Author(s):  
Catherine A. Knock ◽  
H. E. De Wardener

1. Five rats were volume expanded by infusing a volume of blood equivalent to one-third of the estimated blood volume. In six control experiments the same transfusion was given without expanding the blood volume, as an equal volume of blood was simultaneously removed. Sodium excretion increased significantly more after the blood volume was expanded than in the control experiments. 2. Pairs of rats placed on opposite scale pans of a trip balance were cross-circulated by means of arteriovenous bypasses. The blood volume of the rats could be kept constant by keeping the balance in equilibrium. 3. One of each pair of rats received a blood transfusion which either did or did not expand its blood volume. Sodium excretion was measured in the transfused rat and in the recipient rat, the blood volume of which was kept constant. 4. Sodium excretion in the six recipient rats cross-circulated with rats with an expanded blood volume was not significantly different from that in six recipient rats, cross-circulated with rats given a transfusion which did not expand the blood volume. 5. The cross-circulation experiments were repeated, with the difference that the urine of the transfused rat was reinfused. Under these conditions, sodium excretion in 11 recipient rats cross-circulated with blood volume expanded rats was significantly greater than in eight recipient rats cross-circulated with rats given a transfusion which did not expand the blood volume. 6. In cross-circulation experiments in which a blood transfusion was not given urine reinfusion of one rat did not affect sodium excretion of the other rat. 7. It is concluded that the rise in urinary sodium excretion which occurs in an isovolaemic recipient rat cross-circulated with a urine reinfused rat with an expanded blood volume is due to a change in the concentration of a circulating substance.


2005 ◽  
Vol 360 (1457) ◽  
pp. 995-999 ◽  
Author(s):  
Peter A Tass

A model of two coupled phase oscillators is studied, where both oscillators are subject to random forces but only one oscillator is repetitively stimulated with a pulsatile stimulus. A pulse causes a reset, which is transmitted to the other oscillator via the coupling. The transmission time of the cross-trial (CT) averaged responses, i.e. the difference in time between the maxima of the CT averaged responses of both oscillators differs from the time difference between the maxima of the oscillators' resets. In fact, the transmission time of the CT averaged responses directly corresponds to the phase difference in the stable synchronized state with integer multiples of the oscillators' mean period added to it. With CT averaged responses it is impossible to reliably estimate the time elapsing, owing to the stimulus' action being transmitted between the two oscillators.


Parasitology ◽  
1988 ◽  
Vol 96 (2) ◽  
pp. 281-288 ◽  
Author(s):  
T. Nakamura ◽  
T. Konishi ◽  
H. Kawaguchi ◽  
Y. Hayashi

SummaryTwo strains of Eimeria tenella with different decoquinate sensitivity and different glucose phosphate isomerase (GPI) isozymes were used in genetic recombination experiments: a line derived from a laboratory strain (NIAH) was decoquinate-resistant (DR) and had the isozyme GPI-9, while a field isolate (Iwate strain) was decoquinate-sensitive (DS) and had GPI-1. Coccidia-free chickens were orally inoculated with mixed oocysts of the two strains and parasites of the F1 generation were recovered. The F1 progeny showed both forms of the isozyme. Next, oocysts of the F1 progeny were passaged through chickens given the decoquinate-containing diet. The F2 progeny also had GPI-1 and GPI-9, indicating crossfertilization between the two strains. Six single oocysts were isolated from F2 progeny; 1 showed both phenotypes of GPI, 1 had GPI-1 and the remaining 4 lines had GPI-9. Analysis of the amount of GPI in recombinant oocysts suggested that the proliferation rate of the DR strain was slower than that of the DS strain. We concluded that GPI isozymes in E. tenella can serve as useful markers in experiments on chicken coccidia.


Author(s):  
V. Mizuhira ◽  
Y. Futaesaku

Previously we reported that tannic acid is a very effective fixative for proteins including polypeptides. Especially, in the cross section of microtubules, thirteen submits in A-tubule and eleven in B-tubule could be observed very clearly. An elastic fiber could be demonstrated very clearly, as an electron opaque, homogeneous fiber. However, tannic acid did not penetrate into the deep portion of the tissue-block. So we tried Catechin. This shows almost the same chemical natures as that of proteins, as tannic acid. Moreover, we thought that catechin should have two active-reaction sites, one is phenol,and the other is catechole. Catechole site should react with osmium, to make Os- black. Phenol-site should react with peroxidase existing perhydroxide.


1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.


Author(s):  
Philip Isett

This chapter presents the equations and calculations for energy approximation. It establishes the estimates (261) and (262) of the Main Lemma (10.1) for continuous solutions; these estimates state that we are able to accurately prescribe the energy that the correction adds to the solution, as well as bound the difference between the time derivatives of these two quantities. The chapter also introduces the proposition for prescribing energy, followed by the relevant computations. Each integral contributing to the other term can be estimated. Another proposition for estimating control over the rate of energy variation is given. Finally, the coarse scale material derivative is considered.


Metahumaniora ◽  
2017 ◽  
Vol 7 (3) ◽  
pp. 378
Author(s):  
Vincentia Tri Handayani

AbstrakFolklor yang menghasilkan tradisi lisan merupakan perwujudan budaya yang lahirdari pengalaman kelompok masyarakat. Salah satu bentuk tradisi lisan adalah ungkapan yangmengandung unsur budaya lokal dalam konstruksinya yang tidak dimiliki budaya lainnya.Ungkapan idiomatis memberikan warna pada bahasa melalui penggambaran mental. Dalambahasa Perancis, ungkapan dapat berupa locution dan expression. Perbedaan motif acuansuatu ungkapan dapat terlihat dari pengaruh budaya masyarakat pengguna bahasa. Sebuahleksem tidak selalu didefinisikan melalui unsur minimal, tidak juga melalui kata-kata,baik kata dasar atau kata kompleks, namun dapat melalui kata-kata beku yang maknanyatetap. Hubungan analogis dari makna tambahan yang ada pada suatu leksem muncul dariidentifikasi semem yang sama. Semem tersebut mengarah pada term yang diasosiasikan danyang diperkaya melalui konteks (dalam ungkapan berhubungan dengan konteks budaya).Kata kunci: folklor, ungkapan, struktur, makna idiomatis, kebudayaanAbstractFolklore which produces the oral tradition is a cultural manifestation born out theexperience of community groups. One form of the oral tradition is a phrase that containsthe elements of local culture in its construction that is not owned the other culture. Theidiomatic phrase gives the color to the language through the mental representation. InFrench, the expression can consist of locution and expression. The difference motivesreference of an expression can be seen from the influence of the cultural community thelanguage users. A lexeme is not always defined through a minimal element, nor throughwords, either basic or complex words, but can be through the frost words whose meaningsare fixed. The analogical connection of the additional meanings is on a lexeme arises fromthe identification of the same meaning. The meaning ‘semem’ leads to the associated termsand which are enriched through the context (in idiom related to the cultural context).Keywords : folklore, idioms, structure, idiom meaning, cultureI PENDAHULUAN


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