In Unfamiliar England, by Thomas Dowler Murphy : (full image Illustrated)

Books by Thomas Dowler Murphy

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This may offer particular opportunities for evolution of virulence and host-specificity, not seen with other malaria parasites, so studies of ongoing adaptation and interventions to reduce transmission are urgent priorities. The epidemiological emergence of infections can be traced by genotypic analyses, with a high level of resolution when pathogens have a high mutation rate, as illustrated by recently emerged viruses that now have a massive impact on global public health [ 1 , 2 ]. Such analysis is more challenging for eukaryote pathogens with low mutation rate, although it is now clear that the major human malaria parasites Plasmodium falciparum and P.

In contrast, natural human infections by P. Infections have since been reported from throughout southeast Asia, within the geographical range of the long-tailed and pig-tailed macaque reservoir hosts Macaca fascicularis and M. The most highly affected country is Malaysia, where there have been thousands of reported cases and P. It is vital to determine the causes of this apparent emergence, as P. Increasing rates of case detection may reflect better diagnosis, increased transmission by mosquitoes from reservoir host macaques to humans, or parasite adaptation to humans.

Molecular tools to discriminate P. Sequences of parasite mitochondrial genomes and a few nuclear gene loci indicate ongoing zoonotic infection, as human P.

Associated Data

To understand this zoonosis, and to identify whether human-to-human mosquito transmission is occurring, analyses of parasite population genetic structure in humans and macaques should be performed by extensive population sampling and characterisation of multiple putatively neutral loci.

This study presents a P.

Results reveal a profound host-associated sympatric subdivision within this parasite species, as well as geographical differentiation indicating genetic isolation by distance. The existence of two divergent parasite subpopulations, and their admixture in human infections provides unparalleled opportunity for parasite hybridisation and adaptation. Observations of some clinical infections with parasite types that appear intermediate between the two subpopulations may reflect this process, and are a possible result of human-to-human mosquito transmission. Hemi-nested PCR assays were developed for amplification of 19 tri-nucleotide simple sequence repeat loci from throughout the genome of P.

Assays for 11 loci were entirely species-specific for P. These were used to genotype P. We first compared parasites from different host species sampled from Kapit where high numbers of clinical cases are seen Fig 1 , analysing the infections with complete locus genotype data. To allow equally weighted sampling per host, the predominant allele at each locus within each infection was counted for subsequent analysis S1 Dataset. A total of samples were from P.

Additionally, 47 samples were from wild macaques 37 long-tailed and 10 pig-tailed macaques with P. All data for the multiple genotype infections and distribution of identical alleles between infections derived from complete genotyping of 10 microsatellite loci. A Numbers of different P.

B Numbers of identical alleles out of 10 loci in pairwise comparisons of infections, showing a similar diversity among infections in humans and long-tailed macaques, but a higher average identity among infections from pig-tailed macaques. All infections had a different locus genotype, except for 5 of the human infections there was one pair sharing an identical locus genotype, and a triplet of infections sharing another locus genotype, indicated with asterisks here and shown in S4 Table.

Pairwise comparisons of each of the complete locus profiles revealed that all infections in Kapit were genotypically distinct, except for one identical pair and one identical triplet of human infections Fig 2B , S4 Table. There was a much higher average proportion of shared alleles among pig-tailed macaque infections than among those in long-tailed macaques or humans medians of 5, 3 and 2 identical alleles out of 10 loci respectively.

Analysis of allele frequencies revealed that P. A small minority of those which were primarily assigned to either cluster appeared to have a degree of mixed assignment, with scores nearer 0. An independent scan by principal component analysis PCA showed an almost complete separation between parasites from long-tailed macaques and pig-tailed macaques along the first principal component, while parasites from humans covered the whole distribution and overlapped with all of the samples from both of the macaque hosts Fig 3B. Both STRUCTURE and principal component analyses were conducted based on the complete locus genotype dataset from humans, 34 from long-tailed macaques, 10 from pig-tailed macaques.

Cluster 1 is shown in black while Cluster 2 is in red. B Principal component analysis PCA of the genetic divergence among all infections. The percentage of variation captured by each of the first two principal components is shown in brackets. Infections from the different macaque host species are almost completely separated by the first principal component, while human infections are distributed throughout the full range on both axes. We analysed a further human P.

Most human infections had single P. There were no differences in allelic diversity among the different sites H E estimates between 0.

Pairwise comparisons among genotypes from different infections showed a similar level of diversity at each site, with a median of 2 or 3 identical alleles out of 10 loci in each site Fig 4B , S4 Table. Every infection had a different multi-locus genotype, and there were virtually none that shared alleles at more than 7 loci, except for nine pairs of identical haplotypes three pairs in Betong, three in Miri, and one in each of Sarikei, Tenom and Kelantan Fig 4B. Each identical haplotype pair was shared by infections from different individuals sampled at the same site within the same year, except for two of the identical haplotype pairs in Miri, shared by individual infections sampled one and two years apart S4 Table.

A Proportions of infections containing different numbers of genotypes multiplicity of infection, MOI. B Distribution of numbers of identical alleles out of 10 loci in pairwise comparisons of infections. Proportions of isolates assigned as Cluster 2 are highest at the sites in Sarawak top four panels in the figure; locations of all sites are shown in Fig 1.

The Cluster 1 subpopulation was more frequent overall, but Cluster 2 was also common at each of the sites in Sarawak, particularly in Miri and Kanowit where it was more frequent than Cluster 1 S5 Table and S1 Dataset. The degree of P. S5 Table gives details of each of these values for each population.

A principal component analysis of all individual infection genotypes showed that most of the overall diversity is among those defined as Cluster 1 by the STRUCTURE analysis Cluster 2 infections covered only part of the first principal component distribution , and infections from peninsular Malaysia are restricted to part of the second principal component distribution Fig 6B. Black dots denote pairs of populations within Malaysian Borneo and Peninsular Malaysia, while grey dots denote pairs of populations between Malaysian Borneo and Peninsular Malaysia all data are given in S6 Table.

B PCA of the whole infection haplotype dataset indicated differentiation of Peninsular Malaysia isolates from Malaysian Borneo isolates by the second principal component axis, whereas isolates defined as Cluster 1 and Cluster 2 by STRUCTURE analysis were almost completely differentiated along the first principal component axis.

Combination of the macaque samples together with all of the human samples across the 10 geographical locations confirmed the definition of the two P. Quantitative analysis of the proportional Cluster 1 and Cluster 2 ancestry assignments for each infection genotype based on the STRUCTURE analysis yielded an index of the degree of intermediate cluster assignment for each infection.

This has a maximum possible value of 0. An index below 0. We show that human P. In human infections, the long-tailed macaque-associated P. Previous analysis of P. The results confirm that humans have mostly single genotype P. The estimated number of genotypes per infection here is a minimum number based on the alleles detected, and it is possible that some infections may have contained additional parasite clones that were not detected, due to having low density in the blood or having similar alleles to the ones detected. The number of P. Levels of multi-locus linkage disequilibrium in P.

It is unknown how the two sympatric P.

The observation of a single long-tailed macaque with a P. Additional sampling of both long-tailed and pig-tailed macaques will be important to confirm the host associations of different parasites [ 20 ]. Both macaque species are widespread, but long-tailed macaques prefer secondary forest near human settlements where they have access to farms for food, whereas pig-tailed macaques spend more time in ground foraging in primary forests, generally having less frequent contact with humans [ 24 ].

There may be differential susceptibility of mosquito species to the respective parasite types, as suggested for subpopulations of another malaria parasite elsewhere [ 25 ], or different mosquitoes may feed on the respective macaque host species. Genetic differentiation in P. The observation of highest F ST values between populations from Malaysian Borneo and Peninsular Malaysia was expected, as the South China Sea has separated macaques in these areas since the last glacial period [ 26 ], but a test for isolation by distance remained significant when analysing only sites within Borneo.

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A small minority of human infections had intermediate cluster assignment indices, which could potentially result from occasional crossbreeding between the two genotypic clusters, although this cannot be concluded from these data alone. Hybridisation between species or sub-species can offer opportunities for adaptation, and has been associated with emergence of novel host-specificity or pathogenicity in other parasitic protozoa [ 27 ] and fungi [ 28 ].

Switching of host species has occurred repeatedly in malaria parasites of birds [ 29 ] and small mammals [ 30 ], as well as apes and humans [ 3 , 4 ], but the occurrence of parasite hybridisation and introgression has not been investigated. The potential occurrence of inter-cluster hybridisation in even a minority of human P. Genome-wide analysis of P. Human clinical isolates containing single species infections would be relatively straightforward to analyse, as P.

In contrast, as natural macaque infections usually contain a mixture of different malaria parasite species [ 15 ], to obtain unambiguous genome sequences it may be necessary to sequence from individual parasites isolated from these hosts [ 31 ]. Although experimental studies on P. Analysis of phenotypic differences between the different host-associated types may be investigated using both in vivo and in vitro experimental systems, while continued epidemiological and clinical surveillance for increasing incidence or disease severity is of the highest priority.

Human blood samples were taken after written informed consent had been obtained from patients. Animal sampling was carried out as previously described [ 15 ] in strict accordance with the recommendations by the Sarawak Forestry Department for the capture, use and release of wild macaques.

A veterinarian took a venous blood sample from each macaque following anesthesia by intramuscular injection of tiletamine and zolazepam, and all efforts were made to minimize suffering by collecting blood at the trap sites and releasing the animals immediately after the blood samples had been obtained.

The Sarawak Forestry Department approved the study protocol for capture, collection of blood samples and release of wild macaques Permit Numbers: A permit to access and collect macaque blood samples for the purpose of research was also obtained from the Sarawak Biodiversity Centre Permit Number: A total of DNA samples from different P. For samples from Sarawak, DNA was extracted at the University Malaysia Sarawak UNIMAS in Kuching from previously reported blood samples collected between and [ 6 , 10 , 37 , 38 ] as well as new samples collected in and , allowing analysis of five sites: The map locations and dates of the individual macaque sampling is shown in S7 Fig.

The presence of P. Loci with perfect tri-nucleotide simple repeat sequences were carefully selected using customised perl-script commands based on narrow criteria to maximise their likely utility for genotyping: Loci for which primers showed complete specificity of amplification from P.

Genotyping of each microsatellite locus was performed using a hemi-nested protocol with a fluorescent dye-labelled inner primer during the second round PCR amplification primers listed in S1 Table. The PCR cycling conditions were as follows: Infections containing multiple haploid parasite genotypes were apparent as multiple electrophoretic peaks for a locus corresponding to different alleles.

The predominant allele per locus within each infection was counted for subsequent population genetic analyses. Genetic differentiation between each population was measured by pairwise fixation indices F ST using FSTAT, with Bonferroni correction on a nominal significance level of 0. The relatedness of haplotypes between individual isolates was assessed by measuring the pairwise proportion of shared alleles, excluding samples with missing data at any locus. A matrix of pairwise similarity among isolates was calculated based on the identical or mismatched alleles from a complete set of loci and the distribution of shared alleles between sample pairs for each population was visualised using a customised perl-script command.

Individuals in the population pool were clustered to the most likely population K by measuring the probability of ancestry using the multi-locus genotype data. The program parameters were set to admixture model with correlated allele frequency, with 50, burn-in period and , Markov chain MCMC iterations.

In , Russian military spending amounted to 61 billion dollars according to the International Institute of Strategic Studies. France and Germany together spent 90 billion dollars on defence, 50 per cent more than Russia. And yet all these countries spent a much smaller proportion of their GDP on the military than Russia. Russia is not a major player in the field of military spending.

Why Russia is economically weak and politically strong

To have a certain military weight, that country must reserve a much larger share of its GDP for defence than the other countries. To mean something militarily, Russia has to put a heavy burden on its own economy. I come back to my question: Here is an attempt to answer that question. First there is the fact that, at the time of the Soviet empire, Russia built up a nuclear arsenal that, together with the USA, gives this country a unique position in the world.

This means that the country has the capacity to completely destroy the opponent in the event of a nuclear attack on its own territory. No other nuclear power outside the US has that capacity today. Russia is also an important supplier of raw materials, including oil and gas. This gives the country a political lever with regard to Western Europe. It is possible by turning the tap or threatening to do so to exert pressure on a number of European countries.

However, that effect should not be overestimated. Russia also knows that the use of this weapon will in time encourage European countries to find other sources of supply. The power of Russia is limited in this domain because the country does not have a monopoly in oil and gas. Finally, and that is my most important point, Russia is powerful because Europe grants that power to Russia.

Europe has built up an economic union but not a defence union. The European Union is economically 12 times larger than Russia; A huge potential power. However, this economic power is not converted into military and political power because defence has remained a national matter.

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By merging their military capabilities, it would be possible for France and Germany to build a credible defence against Russian threats, without having to spend more. The combined military spending of such a Franco-German defence union would be 50 per cent higher than Russian military spending. Enough to offer a counterweight to a Russian dictator whose political and military ambitions in Europe remain unknown.

If you want peace, you should prepare the war. Translated to the European situation of today this means that Europe should build a credible defense union. This by itself would reduce the military and political power of Russia. He was a member of the Belgian parliament from to His research interests are international monetary relations, monetary integration, theory and empirical analysis of the foreign-exchange markets, and open-economy macroeconomics.

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