Effectiveness of water treatment for the removal of Cryptosporidium and Giardia spp.

Cryptosporidium and Giardia are intestinal parasites of humans and of many other species of animals. Water constitutes an important route of transmission for human infections in both developed and developing countries. In Poland, contamination of water sources with oocysts/cysts is not routinely monitored and scientific research in this field is scarce. Our aim was to compare the contamination of surface and treated water and thus the success of water treatment processes. Water samples (n=94) of between 30 l (surface water) to over 1000 l for tap water, were taken in the period of 2008-2009 using specially constructed equipment with cartridge filtration (Filta-Max; IDEXX, USA). Immunofluorescent assay, and nested polymerase chain reaction were used for the detection of parasites. Cryptosporidium oocysts were found in 85% of surface water and in 59% of raw (intake) water samples. Oocysts were also detected in treated water (16%) but were absent in samples of swimming pool water. The highest mean number of Cryptosporidium oocysts [geometric mean (GM)=61/10 l] was found in samples of rinsing water. Giardia cysts were observed in 61% of surface water samples, in 6% of raw water and in 19% of treated water, with the highest number of cysts noted in rinsing water samples (GM=70 cysts/10 l). Our study highlights the frequent occurrence of parasites in surface waters in Poland and the effectiveness of water treatment for the removal of parasites from drinking water.

Cryptosporidium parvum: the course of Cryptosporidium parvum infection in C57BL/6 mice co-infected with the nematode Heligmosomoides bakeri.

The effects of Heligmosomoides bakeri infection on the course of a concurrent Cryptosporidium parvum infection were studied in C57BL/6 mice. Mice were initially infected with 80 L(3) of H. bakeri and then challenged with 10(4) oocysts of C. parvum, administered during the patent period of the nematode infection (28 day post H. bakeri infection). The number of C. parvum oocysts excreted in the feces and the number of adult H. bakeri in the small intestine were monitored during the experiment. Concurrent H. bakeri infection resulted in a prolonged course of infection with C. parvum. The intensities of both parasite infections were higher in co-infections. We also investigated the cellular immune response at 14 and 42 days post infection C. parvum. During infection with C. parvum there was an increase in production of IFN-gamma and IL-12 but co-infection with H. bakeri inhibited IFN-gamma secretion. The present study is the first to demonstrate that infection with H. bakeri markedly exacerbates the intensity of a concurrent C. parvum infection in laboratory mice and also affects immune effectors mechanisms in co-infection with H. bakeri.

Preliminary molecular characterization of Cryptosporidium parvum isolates of wildlife rodents from Poland.

Isolates of Cryptosporidium were collected from 3 species of woodland and field rodents (Clethrionomys glareolus, Microtus arvalis, and Apodemus flavicollis) and were characterized by polymerase chain reaction amplification and sequencing of fragments of the oocyst wall protein (COWP) gene and of the 18S ribosomal RNA gene. Sequence analysis of these markers revealed that the animals were infected with C. parvum, and that the genotype involved was almost identical to the mouse genotype previously described from Mus musculus. Thus, small rodents should be considered as an important reservoir of C. parvum genotypes closely related to the zoonotic genotype 2 and potentially hazardous to humans.

Prevalence and abundance of Cryptosporidium parvum and giardia spp. in wild rural rodents from the Mazury Lake District region of Poland.

Prevalence and abundance of Cryptosporodium parvum and Giardia spp. were studied in 3 species of rodents from forests and abandoned agricultural fields in N.E. Poland (Clethrionomys glareolus n = 459; Microtus arvalis n = 274; Apodemus flavicollis n = 209). Overall prevalence was consistently higher in the voles compared with A. flavicollis (70.6, 73.0 and 27.8% respectively for C. parvum and 93.9, 96.3 and 48.3% respectively for Giardia spp.). Prevalence and abundance of infection also varied markedly across 3 years with 1998 being a year of higher prevalence and abundance with both species. Fewer older animals (especially C. glareolus and M. arvalis) carried infection with C. parvum and infections in these animals were relatively milder. Although seasonal differences were significant, no consistent pattern of changes was apparent. Host sex did not influence prevalence or abundance of infection with C. parvum, but made a small contribution to a 4-way interaction (in 5-way ANOVA) with other factors in the case of Giardia spp. The 2 species co-occurred significantly and in animals carrying both parasites there was a highly significant positive correlation between abundance of infection with each, even with between-year, seasonal, host age, sex and species differences taken into account. Quantitative associations were confined to the 2 vole species in the study. These results are discussed in relation to the importance of wild rodents as reservoir hosts and sources of infection for local human communities.

[The ecology of Cryptosporidium parvum infection in small rodent populations]. / Srodowiskowe uwarunkowania zarazen Cryptosporidium parvum w populacjach drobnych gryzoni.

The prevalence and abundance of Cryptosporidium parvum were studied over a three year period (1997-1999) in three species of rodents sampled from forest and abandoned fields in the Mazury Lake District, Poland. The overall prevalence was consistently higher in voles compared with Apodemus flavicollis (70.6% in Clethrionomys glareolus, 73.0% in Microtus arvalis and 27.8% in A. flavicollis). The prevalence and abundance of infection also varied across the 3 years of the study with 1998 being the year of higher prevalence and abundance of the parasite. Fewer older animals carried the infection, and their infections were relatively mild. We found no consistent pattern of seasonal changes despite the significance of seasonal differences. Host sex did not influence either the prevalence or abundance of infection with C. parvum. A great proportion of recaptured voles developed chronic infections between consecutive trapping sessions and only a small number of animals recovered. However, yellow-necked mice seem to be much more resistant to infection that became self-limiting. Our results firmly establish that the common woodland and grassland wild rodents in the Mazury Lake District constitute a significant and hazardous reservoir of C. parvum for animals and humans.

Calves as a potential reservoir of Cryptosporidium parvum and Giardia sp.

Studies on cryptosporidiosis and giardiosis were carried out between March and April 1997 on 75 calves from 9 selected farms of Wielkopolska macroregion. Faecal specimens from calves, 3-13 days old, were screened for oocysts of C. parvum using Ziehl-Neelsen staining and both for oocysts of C. parvum and cysts of Giardia sp. using direct immunofluorescent (MerIFluor Cryptosporidium/Giardia) assay. The oocysts of C. parvum assessed by Ziehl-Neelsen staining were revealed on 6 (67%) of 9 farms examined. The prevalence of infection ranged from 20-88%, and in some farms intensity of oocyst shedding was very high. However, in 35 calves assessed for mixed infections of C. parvum and Giardia sp., oocysts of Cryptosporidium were found in 18 (51%) calves and cysts of Giardia sp. were detected in 5 (14%) of 35 calves. Only in one calf was found coinfection with both parasites. The intensity of Giardia sp. infection was extremely low. Histological examination of the gut sections from immunosuppressed BALB/c mice experimentally infected with C. parvum isolates from calves revealed endogenous stages of C. parvum on the brush border of the ileum. The high prevalence and intensive shedding of cryptosporidial oocysts by calves in farms examined in this study suggests that naturally infected calves may be significant reservoirs for C. parvum infections in man and wild animals.

[Evaluation of the efficiency of gemfibrozil in treating hyperlipidemia type IIb and IV]. / Ocena skutecznosci gemfibrozilu w leczeniu hiperlipidemii typu IIb i IV.

Analysis of the efficacy and tolerability of gemfibrozil (Gevilon-Parke Davis) was performed including 29 patients aged 19-69 years with primary hyperlipoproteinemia (HLP) type IIb-16 persons, IV-13 persons. All patients got dietary recommendations and received gemfibrozil 450-900 mg/day for 3 months. In both types of HLP a significant reduction of serum cholesterol (TCh)--15.5% triglycerides (TG)--32.1% VLDL-Ch--34.9% and VLDL-TG concentration--36.6% was observed as well as an increase of HDL3 fraction-16.3%. The greatest reduction of serum TCh concentration and VLDL-Ch were observed in type IIb, while that of TG and VLDL-TG in type IV HLP. The best therapeutic effect was obtained during the first month of treatment. The percent of TCh, TG, VLDL-Ch, VLDL-TG reduction correlated with their initial level. Tolerability of gemfibrozil was very good. Only in 2 patients transient abdominal pain was observed.

Transformation of Thiobacillus versutus with plasmid DNA.

The representative of the facultatively chemolithotrophic thiobacilli, Thiobacillus versutus has been successfully transformed for the first time with plasmid DNA. The plasmid used for the transformation study was pKK2, a derivative of the broad host range pSa plasmid conferring Km resistance being effectively expressed in T. versutus. Different methods inducing an artificial state of competence were tested. Transformants were obtained at the efficiency of about 10(3) per micrograms of DNA. pKK2 appeared to be compatible with T. versutus indigenous plasmids, but for stable maintenance it required constant selective pressure.

The role of hyperinsulinemia in the development of lipid disturbances in nonobese and obese women with the polycystic ovary syndrome.

In order to establish the role of insulin in the pathogenesis of lipid abnormalities in hyperandrogenic women with the polycystic ovary syndrome (PCO) 49 women aged 18 to 35 yr with a normal glucose tolerance test were studied. They were divided into two groups: 27 women with PCO (9 obese and 18 nonobese), and 22 healthy women (12 with simple obesity and 10 with normal body weight). In the PCO group, the fasting insulin levels and the insulin response to oral glucose load were higher than in the matched controls. Significantly lower levels of HDL2-cholesterol and higher levels of apolipoprotein B were observed in obese and non nonobese PCO patients. In obese women with PCO this was associated with lower levels of HDL-cholesterol and apolipoprotein A-I (Apo A-I), whereas the levels of total triglycerides and VLDL-triglycerides (VLDL-TG) were increased. Multiple regression analysis in PCO women, after adjustment for age, body mass index and the levels of insulin and sex hormones, showed a strong positive correlation between the fasting insulin levels and total triglycerides and VLDL-TG, while a negative correlation was found between fasting insulin levels and apo A-I. These results indicate that hyperinsulinemia may play a role in the development of lipid disturbances in women with the PCO.

[Plasma lipid and lipoprotein levels among rural and urban populations in Poland in relation to risk factors of coronary disease]. / Stezenie lipidów i lipoprotein osocza w populacji rolniczej i przemyslowej Polski zaleznie od czynników ryzyka choroby niedokrwiennej serca.

There are significant differences in plasma total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides and blood pressure, prevalence of cigarette smoking, obesity, education level and alcohol consumption found between the rural and industrial populations in Poland. It was found that the differences in plasma lipids and lipoproteins concentration are related to the differences in age, sex, education level, alcohol consumption, obesity, cigarette smoking and blood pressure. Increase of education level was related to increase in plasma concentration of total cholesterol. LDL-cholesterol and triglycerides but it was related to decrease of HDL-cholesterol. After the adjustment to all above factors the differences in total cholesterol and LDL-cholesterol between the studied populations appeared insignificant. The differences in HDL-cholesterol and triglycerides remained significant.

[Effect of coronary disease risk factors on the progression of coronary arteriosclerosis]. / Wplyw czynników ryzyka choroby wiencowej na progresje miazdzycy tetnic wiencowych.

UNLABELLED: A group of 43 patients (pts) from a larger group 451 pts with coronary artery disease (CAD) confirmed by coronary angiography were recatheterized because of deterioration of symptoms. After the first angiography patients had no indications to coronary artery bypass grafting (CABG) or gave no consent to surgery. The group comprised 3 women and 40 men aged 27 to 62 years (mean age 45 +/- 8 years). The mean interval between coronarography was 35 +/- 22 months. Four independent reviewers evaluated 15 segments of coronary arteries according to American Heart Association. The coronary lesions were scored on the basis of reduction in luminal diameter as follows: 0 point = 0-29%, 1 = 30-49%, 2 = 50-69%, 3 = 70-98%, 4 = 90-99%, 5 = 100% occlusion. The influence of the following risk factors on the progression was evaluated: age, sex, hypertension, diabetes, lipid disturbances, smoking, hyperuricaemia, family history. The patients were divided into 3 groups: group I--no or slight progression (0 to 4 points) in two successive coronary angiographies, group II--moderate progression (5 to 9 points) and group II--significant progression (10 points or more). The number of patients in these groups was 14, 12 and 17 respectively. In such isolated groups, the clinical events were compared: unstable angina, myocardial infarctions, need for CABG, cardiac deaths within follow-up period. The ejection fraction of the left ventricle was also evaluated. STATISTICAL ANALYSIS: was conducted by multiple regression model.(ABSTRACT TRUNCATED AT 250 WORDS)

Mn2+ dependent transformation of Bacillus subtilis.

The present study shows that transformation of Bacillus subtilis can proceed in the presence of Mn2+ instead of Mg2+ with equal efficiency. The crucial condition seems to be the Mn2+ concentration which should not exceed 0.025 mM. Binding, uptake and breakdown of donor DNA as well as its physicochemical fate in Mn2+ dependent transformation was investigated. No changes as compared to the standard procedure with Mg2+ were noticed. The possible source of errors in this kind of experiments is discussed.

New types of Escherichia coli K-12 facultative recombination deficient mutants resistant to ultraviolet.

Numerous facultative temperature sensitive recombination deficient mutants of Escherichia coli K-12 strain 108 were isolated after mutagenization with nitrosoguanidine. The majority of the mutants were resistant to UV irradiation. Three mutants, KBP72, KBP169 and KBP610, with marked recombination deificiency (300 to 15,000 times) at 42 degrees C, were UV resistant; their sensitivity to mitomycin C was altered only slightly or not at all. Mutation KBP72 was co-transduced with ilv (83 unit on E. coli genetic map). The mutant is not able to form a functional recombinat structure. Two other mutations are located between 0 and 19 unit of the genetic map.

Replication of plasmid R6K in DNA polymerase deficient mutants of Escherichia coli.

The plasmid R6K has been introduced into a number of Escherichia coli polymerase deficient (pol) mutants. In polCts mutants transferred to the nonpermissive temperature to inactivate polymerase III, R6K replicates but the replication products have a density in dye-CsCl gradients intermediate between supercoiled and linear forms. This aberrant replication requires normal cellular levels of polymerase I since it does not occur in polA polCts mutants. Normal R6K replication and maintenance occur in a polA polB polC+ host, however, we cannot tell from our experiments wheather polymerase I or III replicates R6K in polA+ polC+ host. Polymerase II, the polB gene product, has no detectable role in R6K replication.

Isolation and preliminary characterization of R6K plasmid deletion mutants.

Several deletion mutants of R6K have been isolated by mutagen treatment of bacterial host carrying wild type of the plasmid and search for clones that lost ampicillin or streptomycin resistance. The molecular weight of the mutants as estimated by agarose gel electrophoresis was 15 times 10(6) minus 23 times 10(6) compared to 26 times 10(6) for the parental plasmid. The mutants were characterized in respect of the level of resistance to ampicillin and frequency of conjugational transfer. Some of the mutants were found to differ in Eco RI digestion pattern from the wild type.