Comparative Phylogenetic Studies on Schistosoma japonicum and Its Snail Intermediate Host Oncomelania hupensis: Origins, Dispersal and Coevolution.

Background: Schistosoma japonicum causes major public health problems in China and the Philippines; this parasite, which is transmitted by freshwater snails of the species Oncomelania hupensis, causes the disease intestinal schistosomiasis in humans and cattle. Researchers working on Schistosoma in Africa have described the relationship between the parasites and their snail intermediate hosts as coevolved or even as an evolutionary arms race. In the present study this hypothesis of coevolution is evaluated for S.

High infectivity of Toxocara cati larvae from muscles of experimentally infected rats.

The organ distribution of Toxocara cati larvae in albino rats Rattus norvegicus (n=6/group) experimentally inoculated with 1000 embryonated eggs was examined 1, 2, 3, 7, 30, 90, and 180 days post inoculation (dpi), and the infectivity of recovered larvae was evaluated by bioassay in mice. The intestines, liver, lungs, muscles (carcass) and other organs (heart, brain, spleen, kidneys and genital organs) were digested for larval recovery. Larvae were recovered from all rats, with the mean number of recovered larvae ranging from 13.

Tolerance to low temperatures of Toxocara cati larvae in chicken muscle tissue.

Infectivity of Toxocara cati larvae in muscle tissue of chickens after storage at 4°C and -25°C was assessed in a mouse bioassay to provide information on the risk of meat-borne toxocarosis. Muscle tissue samples of 30-day old T. cati infections were stored at 4°C for 14 and 28 days and at -25°C for 12, 24 and 48 h, whereafter, larvae were released by digestion.

Genetic structure of Ascaris roundworm in Japan and patterns of its geographical variation.

Ascaris roundworm isolates from Japan and central Europe were examined by sequencing analyses to better understand geographically induced nucleotide variation and genotype distribution according to host. Three well-supported clusters (denoted as A, B, C) were identified by generating cox1 sequences of mtDNA from these regions. Among 5 pig isolates collected in eastern Honshu, Japan, in 2010, 3 carried DNA characteristics for cluster A and 2 corresponded with the characteristics of cluster B.

Toxocara cati larvae persist and retain high infectivity in muscles of experimentally infected chickens.

The distribution of Toxocara cati larvae in the organs of chickens (n=31), experimentally inoculated with 3000 embryonated eggs, was examined 1, 2, 3, 7, 29, 86 and 175-176 days post-infection (dpi), and the infectivity of recovered larvae was evaluated by bioassay in mice. The duodenum, liver, lungs, heart, brain, pectoral muscles (white meat), and hindlimb muscles (red meat) of the chickens were HCl-pepsin digested for larval recovery. Larvae were recovered from all chickens [mean=220.

Spatial analysis and remote sensing for monitoring systems of Oncomelania nosophora following the eradication of schistosomiasis japonica in Yamanashi Prefecture, Japan.

In order to develop an inexpensive, simple, and accurate method of monitoring for the reemergence of schistosomiasis japonica in Yamanashi Prefecture, Japan, the distribution and habitation density of the intermediate host, Oncomelania nosophora, were spatially analyzed using geographic information systems. The 1967-1968 density distribution maps prepared by Yamanashi Prefecture and Nihei were digitized and geocoded. The habitats and population density of O.

Yeast-generated CO2 as a convenient source of carbon dioxide for adult mosquito sampling.

A new, convenient method was developed to supply CO2 for mosquito sampling by using yeast, which converts sugar into CO2 and ethyl alcohol. The system could, at average, generate 32.4 ml/min of CO2 for at least 27 h.

Fixed-point observation of Oncomelania nosophora in Kofu Basin--establishment of monitoring system of schistosomiasis japonica in Japan.

There are still many Oncomelania snails that inhabit the Kofu Basin, Yamanashi Prefecture, Japan, which had been declared free of schistosomiasis japonica. Due to the need to monitor the situation, a fixed-point observation system using GIS from GPS is being examined. In addition, in broad present or former endemic areas, survey areas are being managed by remote sensing with satellite images or aerial photographs.