No description available.

No description available.

No description available.

The phospholipase B activity was assayed in the small intestines, spleen and liver/bile duct of nonsensitized and sensitized mice infected with Fasciola hepatica. The primary infection resulted in a significant increase in phospholipase B activity in the small intestine, spleen and liver/bile duct over that of uninfected control animals. The response to the challenge infection was characterized by an earlier increase in enzyme activity with values significantly above those found for the primary infection in the same tissues. These data demonstrate that one response of mice to infection with F. hepatica is characterized by an increased phospholipase B activity. Thus, the enzyme response is not unique to cestode and nematode infections, but also is part of or associated with the inflammatory mechanisms against trematode infections. In addition, phospholipase B was demonstrated in leukocytes using electron microscopic histochemical techniques. Leukocytes were harvested from peritoneal exudates of mice. Cells were fixed in 4% calcium-forol fixative for 30 minutes at roan temperature for electron microscopy, after which they were incubated at 370C in medium at pH 6.6 containing 2 aM lysolecithin and Cal2 . The fatty acids released during the hydrolytic reaction were trapped as a calcium precipitate and were converted to a lead precipitate for electron microscopy by treatment with lead nitrate. The reaction products were observed to be present in eosinophils and absent in neutrophils, lymphocytes and macrophages. It is concluded that the eosinophilic leukocyte is the carrier cell for phospholipase B in inflanmatory reactions.

25th International Conference of the World Association for the Advancement of Veterinary Parasitology. 16-20 Ago. 2015. UK / Fascioliasis, caused by Fasciola hepatica, is a public health problem in Peru, especially in schoolchildren. Prevalence rates in livestock are over 80% in dairy cattle reared in the Andean valley of Cajamarca, Peru. The present investigation aimed to determine the prevalence of F. hepatica infection in schoolchildren and the main risk factors involved in its presentation. Two hundred and seventy schoolchildren nine years old and over from primary public institutions from the district of Los Baños del Inca (Cajamarca) were included in the investigation. Questionnaires were applied to parents and children and fecal samples were taken and evaluated using the rapid sedimentation technique. Blood samples were also collected and analyzed. Seventeen fecal samples were positive to F. hepatica eggs, giving a prevalence of 6.3% (95% CI 3.21 - 9.38). Significant differences were found with origin of the child, history of intestinal parasitism, and the habit of chewing grass (p< 0.05). The rural origin (OR 4.8, 95% CI: 1.53-15.08) and the habit of chewing grass (OR 3.26, CI: 95% 1.07 - 9.96) were the most likely risk factors associated with the acquisition of infection. The leukocyte count of infected children varied between 3900 and 10580 cells /mm3 (mean ± SD = 6458.3 ± 2080.3). Thirty three percent of children positive to F. hepatica eggs presented eosinophilia. We conclude that the prevalence of human fascioliasis in the district of Los Baños del Inca is at the mesoendemic level and rurality provides conditions for acquiring the infection.

Angus-sired heifers were allotted by age (mean=4 mo), BW (mean=135 kg), and sire (n=4) to either a control (n=10) or infected group (n=11; 600 metacercariae of Fasciola hepatica, intraruminally) to test our hypothesis that puberty is delayed by experimental fascioliasis. Blood samples were collected biweekly for analysis of steroid hormone concentrations. At 2-wk intervals, BW was recorded, and samples were collected for analysis of liver enzymes and serum proteins and fecal egg counts. A radiotelemetry system (HeatWatch??) was used to detect estrus and ovulation was confirmed by an elevation in serum progesterone (P4) after estrus. Heifers were artificially inseminated (AI) at the second observed estrus. Serum &#947;-glutamyl transpeptidase (GGT) and aspartate aminotransferase (AST) increased (p<0.0008) between day 0 and 112 in the infected group. Serum estradiol (E2) and P4 concentrations did not differ (p>0.1) between treatment groups. Mean age at puberty was 10 days later (p>0.1) in the infected group. Conception rate did not differ between control and infected heifers. The HeatWatch?? data were used to compare mounting activity during estrus in pubertal and gestating heifers. Mean duration of estrus was longer (p<0.01) for the second than for the pubertal estrus, though total mount duration and number of mounts did not differ. Number of mounts at second estrus was greater (p<0.05) for heifers that conceived (n=9). Mean duration of estrus and total mount duration at second estrus were not associated with pregnancy outcome. Estrus events were detected in all nine heifers during pregnancy (total=73). A majority (75%) of the interestrus intervals during gestation was <17 d. Number of mounts (p=0.035) and total duration of mounts (p=0.022) at second estrus were predictive of number of mounts during gestation. Experimental infection of Fasciola hepatica did not alter serum steroid hormone concentration or delay pubertal development in heifers. Estrus duration was longer for the second estrus compared to the pubertal estrus, and the number of mounts received during the second estrus was greater in heifers that did conceive to AI. Estrus events were detected in each heifer during pregnancy; however, a normal interestrus interval occurred in only 10% of the estrus events.

ntroduction: Fasciola hepatica is a parasite of the class Trematoda. It commonly has been found in developing countries. When it infects humans is characterized by a triad of fever, pain in right upper quadrant and peripheral eosinophilia. We present a 67-year-old female from a rural town of the north of Lima, Peru, it was found abdominal pain, eosinophilia and focal hepatic lesions. For this reason, a hepatic mass was the initial suspicion. The hepatic biopsy was performed and one of the findings was eosinophilia. Fasciola hepatica infection should be considered as part of differential diagnosis in hepatic tumors with eosinophilia when the origin of the patient is from endemic areas of F. hepatica. / Fasciola hepática es un parásito de la clase Trematoda común en países en desarrollo. La infección en el ser humano se caracteriza por la triada de fiebre, dolor abdominal en el cuadrante superior derecho y eosinofilia. Se presenta el caso de una mujer de 67 años procedente de una zona rural al norte de Lima, con historia de dolor abdominal de seis meses de evolución, con una imagen hipodensa hepática en el TAC abdominal y eosinofilia. La biopsia hepática mostró un infiltrado inflamatorio con eosinofilia. En el diagnóstico diferencial en pacientes con un tumor hepático y eosinofilia, se deben incluir infecciones parasitarias como F. hepatica; sobre todo en pacientes que proceden de áreas endémicas.

Schistosoma mansoni and Fasciola hepatica are parasitic trematodes which contain cytochrome c peroxidase (CcP) in their mitochondria, an enzyme that is absent in mammalian tissues. CcP reduces hydrogen peroxide to H2O using cytochrome c as the electron donor. Both parasites are catalase deficient; thus, cytochrome c peroxidase and glutathione peroxidase are the enzymes involved in the detoxification of H2O 2 in these organisms. The enzymatic activity of these two peroxidases may enable S. mansoni and F. hepatica to survive oxidative stress. The main objective of this study was to characterize cytochrome c peroxidase from S. mansoni and F. hepatica . Kinetic studies of this enzyme in crude homogenate and isolated mitochondria of S. mansoni were initially performed, followed by purification studies from S. mansoni and F. hepatica . The parasite enzyme has affinity for horse heart and yeast cytochrome c and it is inhibited by sodium azide and potassium cyanide. CcP was purified close to homogeneity and identified as a protein containing heme. The antioxidant capability of F. hepatica CcP was tested in vitro , demonstrating that CcP protected the sugar deoxyribose from oxidative degradation. Exposure of adult worms to H2O2 caused a decrease in S. mansoni CcP activity in vivo. An attempt was made to clone the S. mansoni CcP gene. The experiments did not result in the cloning of the CcP gene, but led to the identification and cloning of another protein, a component of a cytosolic chaperonin, t-complex polypeptide one (TCP-1). TCP-1 from S. mansoni is highly homologous to TCP-1 proteins from different organisms including, Chinese hamster, human, Drosophila and yeast and carries ATP binding amino acid motifs indicating that it has ATPase activity.

No description available.

Thesis (Ph.D.) - James Cook University, 2005. / Includes reprints of short communications published inTropical Animal Health and Production, 37 (2005), p. 215-221 and p. 451-455. Typescript (photocopy) Bibliography: leaves 108-127.