Transmission and course of parasitemia of Babesia microti (Hannover I strain) in the bank vole (Clethrionomys glareolus) and field vole (Microtus agrestis)

In Germany only M. agrestis has been found to be naturally infected with B. microti while in other European countries several rodent species were found as mammalian hosts. In the laboratory C. glareolus got easily infected by German strains of B. microti, if parasitized blood was inoculated. But results of this method are not transferable to natural conditions. Therefore this study was carried out. It was to prove whether C. glareolus is susceptible to B. microti transmitted by nymphs of I. ricinus, or not. To compare the results, M. agrestis was infected in the same way. Both of them proved to be susceptible. The parasitaemia lasted for months. In the beginning the rate of parasitaemia reached 2%, then decreased below 0.1%. The course of infection was variable. In blood smears B. microti could not be detected at all times, so that in field trials the infection rate in mice will often be underestimated. A connection between parasitaemia and gravidity or lactation was not observed under laboratory conditions.     

Brucellosis of the common vole (Microtus arvalis)

A systemic disease occurred in a wild population of the common vole Microtus arvalis in South Moravia (Czech Republic) during the years 1999-2003. Acute infections were characterized by edema of extremities, occasionally with colliquating abscesses, arthritis, lymphadenitis, perforations of the skin resulting from colliquated abscesses, orchitis, and peritoneal granulomas. From the clinical samples, small Gram-negative coccobacilli were isolated and identified as Ochrobactrum intermedium by API 20NE and colistin sensitivity profiles. However, subsequent rrs (16S rRNA) and recA (recombinase A) gene sequencing analysis of two isolates (CCM 4915=CAPM 6434; CCM 4916=CAPM 6435) identified them as Brucella sp. with sequence identities of 100% to other Brucella spp. Analysis of the omp2a/b genes confirmed the two isolates as Brucella. In AMOS polymerase chain reaction (PCR), a 2000-bp fragment was generated that was not seen in other brucellae. Experimental infection of outbred ICR mice with these isolates resulted in a mortality rate of 50%. Based on the results of the molecular investigations and the mortality observed in experimentally infected mice we conclude that the epizootic was caused by Brucella sp. and not by Ochrobactrum intermedium. The study demonstrates the limitations of commercial biochemical test systems in accurately differentiating among Ochrobactrum and Brucella.     

都匀亚洲带绦虫与牛带绦虫比较的Meta分析

本文采用Meta分析方法对文献报道的都匀亚洲带绦虫研究结果进行了综合分析，得出的结果支持“都匀牛带绦虫”为都匀亚洲带绦虫的结论。     

New concepts in the diagnosis and management of neurocysticercosis (Taenia solium)

Human neurocysticercosis, the infection of the nervous system by the larvae of Taenia solium, is a major cause of epileptic seizures and other neurologic morbidity worldwide. The diagnosis and treatment of neurocysticercosis have been considerably improved in recent years. This improvement includes identification and sequencing of specific antigens and development of new assays for laboratory diagnosis, recognition of the frequency and significance of edema around old, calcified cysts (associated to symptomatic episodes), results of a randomized blinded control treatment trial on treatment efficacy for intraparenchymal disease showing a clinical benefit of decreased seizures, and a much better assessment of the frequency and spectrum of cerebrovascular complications. These advances now permit a much better integration of clinical, serologic, and imaging data for diagnosis and therapeutic purposes.     

Studies of secretory activity and pathomorphology of the gastric mucosa in taeniasis (Taenia saginata)

Studies were performed on 149 patients, aged 18 to 50, hospitalized in the Department of Parasitic and Tropical Diseases, Medical Academy in Poznań. The following examinations were performed: gastric contents testing with histamine stimulus according to Kay, the histological and cytological examination of gastric mucosa biopsies. Among patients with Taenia saginata invasion, disturbances in secretory activity of gastric mucosa were demonstrated in 57.7% of studied patients. Hypoacidity was found in 49.7% of patients; it appeared both in the oldest group, over 40 years (71.4%), as well as in two younger, although at two times lower frequency (38.2 and 39.6%, respectively). At set of histological and cytological studies was performed on gastric mucosa biopsies in a chosen group of 30 patients (average age of 26.2 years) with taeniasis and hypoacidity, before and after the treatment of the invasion. Before the treatment cellular infiltrates consisting of mononuclear cells were observed in gastric mucosa biopsies; cytological analysis of gastric gland cross-sections demonstrated 3 to 4 times lower number of parietal cells as compared to that of mucous cells. After the treatment of taeniasis, secretory activity of gastric mucosa returned to the normal level in 20 patients (66.7% of total). At the same time, the histological and cytological analysis of the biopsies showed decreased intensity of cell infiltrates in the glandular layer of the mucosa and an increased number of parietal cells as compared to the number of mucous cells. In 10 patients (33.3% of total), hypoacidity of the gastric juice as well as gastric mucosa lesions persisted despite the elimination of T. saginata. No relation could be found between the duration of T. saginata invasion on the one hand and secretory disturbances on the other. The subsidance of functional disturbances in gastric mucosa and of their morphological exponents in 2/3 of patients after taeniasis treatment indicates a causal relationship between time of taeniasis and secretory disturbances and histological lesions in gastric mucosa.     

Experimental studies of Korea Taenia (Cheju strain) infection in domestic animals

In the present study, one DYL pig (five-day old), four L-SEM pigs (37-day old), three SEM pigs (44-day old), one Holstein calf (eight-day old) and two Sannean goats (five-day old) were each fed 1000, 30,000, or 380,000 eggs of the Korea Taenia (Cheju strain) and were sacrificed 16-105 days after inoculation. All DYL, L-SEM, and SEM pigs and the Holstein calf were susceptible to Korea Taenia, and one of the two Sannean goats became infected. The cysticerci recovery rates for L-SEM, SEM and DYL pigs, Holstein calf, and Sannean goat were 5.6, 1.7, 0.06, 0.03 and 0.02% respectively. Cysticerci were recovered only from the livers of the infected animals, and more cysticerci were found in the parenchyma (51%) than on the surface of the liver (49%). Immature cysticerci were first observed on day 16 after infection, mature ones on day 29, and degenerated or calcified cysticerci on day 30. Inoculation of a huge number (380,000) of Korea Taenia eggs lead to early degeneration or calcification of the cysticerci. The length, the width, and the diameters of protoscolex, rostellum, and sucker of the cysticerci were largely proportional to the period of inoculation. The measurements and patterns of the hooklets indicate that Korea Taenia is very similar to Taiwan Taenia but is different from T. saginata and T. solium. The results of the present study provide evidence that Korea Taenia and Taiwan Taenia may be of the same species.     

Helminth antigens (Taenia solium, Taenia crassiceps, Toxocara canis, Schistosoma mansoni and Echinococcus granulosus) and cross-reactivities in human infections and immunized animals

Helminth antigens were investigated in the search for accessible heterologous antigens capable to discriminate different helminthiases, by the enzyme linked immunosorbent assay (ELISA) and the immunoblot assay (IB). Antigens used were: Taenia solium cysticercus total saline (Tso); Taenia crassiceps cysticercus vesicular fluid (Tcra-VF); T. crassiceps cysticercus glycoproteins (Tcra-GP and Tcra-(18-14)-GP); Toxocara canis larva excretory-secretory (TES); Schistosoma mansoni adult total saline (Sm) and Echinococcus granulosus hydatid fluid (Eg). The assayed sera were from patients with: cysticercosis (n = 18); toxocariasis (n = 40); schistosomiasis (n = 19) and hydatidosis (n = 50) with proven clinical and laboratory diagnosis, and sera from rabbits immunized with Tso, Tcra-VF, TES and Eg. Cross-reactivity occurred mostly between infections caused by Taenia and Echinococcus or in immunized rabbits, by ELISA. Moreover, the cross-reactivity among helminthiases was found with the use of antigens belonging to phylogenetically related parasite species, Eg, Tso and Tcra-VF, by sharing same antigenic components. Lower cross-reactivities were obtained by IB technique, when only peptides were considered as antigens, and the use of T. crassiceps purified glycoproteins demonstrated high sensitivity and specificity in the diagnosis of human cysticercosis, similarly to that using homologous antigen (Tso) by the same technique.     

Bisphenol A affects endocrine physiology and biotransformation enzyme activities of the field vole (Microtus agrestis)

Bisphenol A (BPA), an environmental estrogen, was given subcutaneously for 4 days to 48 field voles at three doses (10, 50, or 250 mg kg(-1) day(-1)). Plasma sex steroids, thyroxine, weight-regulatory hormones, and liver biotransformation enzymes were determined. There was no mortality in the control group but the mortality in the BPA-exposed animals was significant. BPA increased the plasma testosterone concentrations at 250 mg BPA kg(-1) day(-1). The plasma ghrelin levels measured from pooled plasma increased and at the same time the leptin levels measured from pooled plasma decreased at 50 or 250 mg BPA kg(-1) day(-1). The liver 7-ethoxyrufin-o-deethylase activity decreased slightly at all doses, as did the liver cytosolic glutathione S-transferase activity at 250 mg BPA kg(-1) day(-1). The results show that wild mammals such as the field vole could be more susceptible to BPA than laboratory rodents. More studies on wild mammals are needed to determine the risks of endocrine disruptors in natural ecosystems.     

Effects of peripheral ghrelin on the carbohydrate and lipid metabolism of the tundra vole (Microtus oeconomus)

Ghrelin is a novel orexigenic peptide hormone. In humans and rodents, it increases food intake and its levels are reduced in obesity but increased in fasting. It is an antagonistic signal to leptin informing the central nervous system about negative energy balance. The tundra vole (Microtus oeconomus) is an interesting model to study the effects of ghrelin, as it is poorly adapted to fasting. In this study, 10 male voles were injected with intraperitoneal ghrelin at 10 microg kg(-1)day(-1) for four days, while 10 males received sham injections. Additional five males were food deprived for 4 h with five males as fed controls. Exogenous ghrelin caused an expected elevation in the plasma ghrelin concentrations. Furthermore, the plasma glucose and high density lipoprotein cholesterol concentrations increased but the kidney and muscle glycogen contents decreased. The liver lipase and kidney glycogen phosphorylase activities increased at the same time. Food deprivation caused an increase in the plasma ghrelin concentrations. In voles, ghrelin may be a mediator to recruit body energy reserves during negative energy balance that would be detrimental to voles very rapidly if foraging does not prove to be successful.     

Serological evidence of viruses naturally associated with the montane water vole (Arvicola scherman) in eastern France

We surveyed 12 populations of the montane water vole (Arvicola scherman), previously known as the fossorial form of the water vole A. terrestris, in eastern France for antibodies (immunoglobulin G) to Puumala virus (PUUV), lymphocytic choriomeningitis virus (LCMV), and cowpox virus (CPXV). Antibodies to PUUV were found in 9 (5.5%) of 164 voles from 7 populations, antibodies to LCMV were found in 13 (26.0%) of 50 voles from 2 populations, and antibodies to CPXV were found in 66 (41.8%) of 158 voles from 7 populations. Antibody status to CPXV was statistically associated with the phase of the A. scherman population density cycle and the percentage of grassland areas surrounding the sampling sites.