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The motility parameters of Fasciola hepatica miracidia were assessed at different temperatures and times post-hatching using computer-assisted sperm analysis. Eggs were incubated at 22°C or 25°C for 14 days. Five motion parameters were evaluated at different incubation temperatures up to 10 h post-hatching. No differences were observed in the percentage that hatched after incubation at the two different temperatures. However, the straight-line velocity of miracidia following incubation at 22°C was significantly different from that observed at 25°C (P< 0.01). All miracidium motion parameters at different post-hatching temperatures showed an overall decrease at the end of the experiment. Those miracidia hatching from eggs incubated at 25°C had a higher velocity of 1673.3 μm/s compared with 1553.3 μm/s at 22°C. Velocity parameters increased as the post-hatching temperature increased from 22°C to 37°C. [ABSTRACT FROM AUTHOR]

The aims of this study were to determine the frequency of egg shedding (percentage of egg-positive faecal samples) and faecal egg counts (FEC) over 13 months in two different breeds of ewes, both pregnant and non-pregnant, in a mountainous region of central Mexico. Additionally, the effect of ivermectin and albendazole treatments on FEC reduction was recorded. The study also aimed to relate temperature and rainfall to FEC. The gastrointestinal nematode (GIN) third-stage larvae genera recovered from both faeces and grassland pastures in a temperate region were also assessed. Faecal samples were collected from ewes at monthly intervals for 13 months to investigate the FEC population of GIN larvae, their concentration and genera in grass samples collected from grazed and rested pastures. Egg-shedding frequency ranged from 0 to 92% and FEC from 0 to 12,000 eggs per g faeces (epg), with counts in Suffolk higher than in Dorset ewes. The identified genera were Haemonchus, Trichostrongylus, Teladorsagia, Cooperia, Oesophagostomum, Bunostomum, Nematodirus and Strongyloides. Haemonchus and Trichostrongylus were the most common genera. The number of L3 was higher in grazing lands than in those at rest. The highest FEC were recorded in the dry season due to peripartum, but the highest L3 counts were recorded in the rainy season. The coexistence of species of different geographical distributions at this site may be because there is a confluence of Nearctic and Neotropical geographic regions; thus, despite the temperate climate, tropical species can be found. Additionally, this study suggests that increasing temperatures could favour the presence of different tropical GIN species together with typical temperate-zone GIN species. [ABSTRACT FROM PUBLISHER]

In vitro interaction of Entamoeba histolytica trophozoites with fibronectin (FN) induces redistribution of the amoebic fibronectin receptor (β1 EhFNR). Trafficking of beta1 integrins is important for cell adhesion and migration in higher eukaryotes and requires the participation of Rab proteins. In E. histolytica, the machinery involved in integrin trafficking is not completely known. EhRab7 is a 24.5-kDa protein whose alignment with other Rab7 proteins demonstrated that it shared significant homology with Rab7 proteins from other organisms, including humans. Using different types of microscopy (fluorescence and confocal microscopy), it was established that Rab7 and the actin cytoskeleton participated in the mobilization of β1 EhFNR in FN-stimulated trophozoites. β1 EhFNR and Rab7 co-localized only in vesicular structures at 5 min, and at longer time (1 h), both co-localized in both plasma membrane and in vesicular structures; at the same time, Rab7 co-localized with specific actin structures (phagocytic vacuoles). At 5 h the β1 EhFNR, Rab7, and actin co-localized at the plasma membrane, and only β1 EhFNR and Rab7 decorated vesicles of different sizes. Actin and Rab7 co-localized in a cap-like structure at one end of the cell. Fluorescence resonance energy transfer and electron microscopy confirmed the close interaction between β1 EhFNR and Rab7. Moreover, the use of a lysosome-specific marker (LysoTracker) and a Golgi-specific marker (NBD C6-ceramide) allowed us to establish that, at some point within the endocytic route, β1 EhFNR and Rab7 co-localized within a lysosome-type organelle, but not a Golgi-like organelle, which indicated that this integrin-like molecule was returned to the plasma membrane via exocytic or secretory vesicles.Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

By employing Neodymium-hexafluoro-pentanedionate and Iron-pentanedionate as chemical precursors, we are able to grow (Nd,Fe)O1-yF1+2y thin films by aerosol assisted chemical vapor deposition with different Nd:Fe atomic ratios (Nd1-xFe_x; 0\leq x\leq 1). The X-ray diffraction and energy dispersive experiments, indicate that for compositions of x\leq 0.5, the as grown films crystallize in the tetragonal off-stoichiometry Nd-oxyfluoride structure (NdO1-yF1+2y, spatial group P4/nmm), while for x>0.5 the films develop an amorphous phase. Given that we are able to grow films with x\approx0.5, the (Nd,Fe)O1-yF1+2y films with this particular Nd/Fe concentration have been employed in diffusion experiments to try to introduce arsenic and develop the NdFeAsO1-yF_y. The preliminary results indicate that the arsenic is not efficiently incorporated into the precursor film; however the diffusion promotes the recrystallization of the as grown films in the stoichiometric Nd1-xFe_xOF rhombohedral phase (spatial group R-3m). The electrical characterization of those films indicates that most of them are semiconductors. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Recombinant human erythropoietin (RHuEPO) is an erythropoiesis stimulating agent (ESA) used to treat anemia in patients with total or relative erythropoietin deficit. In cancer patients, it is administered to optimize hemoglobin (Hb) levels, correct anemia and reduce the need for transfusions. Cuba produces a RHuEPO, registered in 1998 as ior®EPOCIM, that is widely used in the national public health system, mainly to treat patients with anemia due to chronic kidney disease (CKD). OBJECTIVE: Evaluate the efficacy and safety of ior®EPOCIM in pediatric cancer patients with anemia following chemotherapy or radiotherapy. The working hypothesis posed an Hb increase >/=15 g/l in 70% of patients receiving ior®EPOCIM for 8 weeks. METHODS: A Phase IV, multicenter, open clinical trial was conducted. Participants were 157 patients aged 1DS19 years with anemia and cyto-histological diagnosis of cancer in any location. Patients received either 600 U/kg ior®EPOCIM intravenously, once weekly, or 150 U/kg ior®EPOCIM subcutaneously, 3 times a week, for 8 weeks. All patients had blood tests every week to determine hemoglobin and hematocrit, and reticulocyte and platelet counts. Mean number of transfusions required by patients during the treatment period was compared to the mean number of transfusions received in the preceding 8 weeks. Adverse events (AE) were recorded at the 4th and 8th weeks and classifi ed by intensity and causality. RESULTS: Hb levels rose >/=15 g/l in 68.8% of patients, and transfusion requirements decreased 17%. The most frequent adverse events were fever (19.3%), vomiting (10.2%) and flu-like syndrome (9.6%). Intensity of AE was predominantly mild. Only 7 AE were classifi ed as very probably related to the product and none of those was severe. CONCLUSIONS: ior®EPOCIM proved to be safe and effective at the doses and frequencies used in this patient population. As a result, this medication was recommended for use in all pediatric oncology and hematology services in the country. [ABSTRACT FROM AUTHOR]

Understanding seedling performance across resource gradients is crucial for defining the regeneration niche of plant species under current environmental conditions and for predicting potential changes under a global change scenario. A 2-year field experiment was conducted to determine how seedling survival and growth of two evergreen and two deciduous Quercus species vary along gradients of light and soil properties in two Mediterranean forests with contrasting soils and climatic conditions. Half the seedlings were subjected to an irrigation treatment during the first year to quantify the effects on performance of an alteration in the summer drought intensity. Linear and non-linear models were parameterized and compared to identify major resources controlling seedling performance. We found both site-specific and general patterns of regeneration. Strong site-specificity was found in the identity of the best predictors of seedling survival: survival decreased linearly with increasing light (i.e. increasing desiccation risk) in the drier site, whereas it decreased logistically with increasing spring soil water content (i.e. increasing waterlogging risk) in the wetter site. We found strong empirical support for multiple resource limitation at the drier site, the response to light being modulated by the availability of soil resources (water and P). Evidence for regeneration niche partitioning among Quercus species was only found at the wetter site. However, at both sites Quercus species shared the same response to summer drought alleviation through water addition: increased first-year survival but not final survival (i.e. after two years). This suggests that extremely dry summers (i.e. the second summer in the experiment) can cancel out the positive effects of previous wetter summers. Therefore, an increase in the intensity and frequency of summer drought with climate change might cause a double negative impact on Quercus regeneration, due to a general reduction in survival probability and the annulment of the positive effects of (infrequent) ‘wet’ years. Overall, results presented in this study are a major step towards the development of a mechanistic model of Mediterranean forest dynamics that incorporates the idiosyncrasies and generalities of tree regeneration in these systems, and that allow simulation and prediction of the ecological consequences of resource level alterations due to global change. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the performance of a detailed ultrasound examination during the second trimester as a screening test for Down syndrome in an unselected Chilean population. Methods: This was part of an ongoing longitudinal study. Included were 3071 women with singleton pregnancies who underwent routine ultrasound examination between 21 + 0 and 25 + 6 gestational weeks as a screening test for chromosomal abnormalities and major congenital structural defects, and who were diagnosed as having trisomy 21 or being chromosomally normal. Maternal age, and eight soft markers and cardiac defects associated with Down syndrome were evaluated as a screening test using logistic regression analysis. Results: The incidence of Down syndrome was 0.6%, and the mean maternal age was 29.4 +/- 6.2 years. At least one of four soft markers (absent nasal bone, nuchal edema, short femur, echogenic foci) and/or cardiac defects was present in 77.8% of Down syndrome fetuses and in 3.1% of normal fetuses. Furthermore, with a false-positive rate of 1%, the detection rate using the combined model of ultrasound markers and maternal age was 72.2%. Conclusions: Second-trimester ultrasound markers are able to detect over 70% of Down syndrome fetuses with only a 1% false-positive rate. [ABSTRACT FROM AUTHOR]