Human-threatened ecosystem: new signs of groundwater connection between Yacyreta reservoir and Ibera wetland (South America)

Ibera wetland is one of the most pristine and singular ecosystems of South America. Satellite-derived thermal analysis of its lacustrine system supported the existence of a groundwater connection with the Yacyreta reservoir through basaltic fractures located along the ancient river bed of the Parana. The groundwater outflow would be located on the geological discontinuity of the eastern border of Ibera wetland, concretely Laguna Ibera and Laguna Luna-Disparo. This new sign of connection comes on top of the hydrological signs which already exist. A call to prudence recommends not extending the recently projected increase of the water level of Yacyreta reservoir. Deeper hydrogeological studies should analyze the hypothesis emerged from this study before modifying the water level of Yacyreta.

Montelukast in early childhood asthma. Predict value of IgG in clinical reply in children 2 to 5 years old?

BACKGROUND

According to current knowledge, asthma is basically an inflammatory process. Its causes and physiopathological mechanisms are various. The final result is a recurrent obstructive bronchial process, with sibilants and/or dypnea, which causes an upset in functional respiratory tests, among which the maximum respiratory peak flow meter diminished for the age, sex, and height of patient.

AIMS

Our aim is to evaluate if response to treatment with Montelukast has any link with immnuloglobin values (IgG, IgA, IgM, IgE) at start of treatment.

MATERIALS AND METHODS

Included in the study were 32 children, of whom 2 did not begin and 1 who did not provide personal data. There were 29 patients in total, 11 girls and 18 boys. Each made three visits: first where they were instructed, together with their parents, in how to manage the meter and where they received the peak flow meter, Vitalograph, and personal data sheet, where personal and family medical history were noted. The second visit was after 4 weeks, for a clinical assessment and the third visit after 8 weeks. The value register of the PEF would be made morning and night, noting the highest value of three measurements. IgG, IgA, IgM, IgA values were quantified before treatment began. The statistic package STATA 2001 was used in the treatment of data statistics.

RESULTS

Our between the value reached by the PEF after treatment and the IgG values at the beginning of treatment (0.712). In lesser measurement for IgA values (0.660). For each 100 mg/ml of increase in the value of IgG, an increase of 10 l/min in the PEF measurement before and following treatment with Montelukast was produced.

CONCLUSIONS

IgG values increase with age. Children with a greater IgG value at the beginning of treatment reached higher PEF values after same. It is not known if the results would be similar with another type of treatment and the way in which IgG influences the results. What appears to be confirmed by available studies is that this relation is found in a group of small children, the aim of our study.

Experimental porcine rubulavirus (La Piedad-Michoacan virus) infection in pregnant gilts

Porcine rubulavirus (La Piedad-Michoacan virus) (PoRV-LPMV) is a member of the Paramyxoviridae family that causes encephalitis in young piglets and infertility in adult sows and boars. Infertility in sows naturally infected by PoRV-LPMV is characterized by an increased number of returns to oestrus, stillbirths and mummified fetuses. In this study, nine seronegative gilts were inoculated intranasally with the PAC-3 strain of PoRV-LPMV at week 6 or 10 of gestation. These animals were then killed at weeks 8 or 15 of gestation (seven gilts) or after natural parturition (two gilts). Four control gilts were mock-infected at gestation week 6 or 10 and killed between 2 and 4 weeks later. Gross lesions of focal congestion and haemorrhage were seen in the placenta and endometrium of one gilt infected at gestation week 6 and one infected at gestation week 10. PoRV-LPMV was isolated, at 2-6 weeks post-inoculation (pi), from lung, tonsils, ovary, placenta, uterus and lymph nodes of three of the gilts infected at gestation week 6 and at 2-3 weeks pi from lung, tonsil and ovary of two gilts infected at gestation week 10. Many of the fetuses of eight infected gilts were smaller than normal and had dermal ecchymoses. Dehydrated or mummified fetuses were present in six of the infected gilts but not in any control animal. PoRV-LPMV was isolated from brain, lung and liver of fetuses from two gilts infected at gestation week 6, and from two infected at gestation week 10. These results indicate that, after experimental infection, PoRV can replicate in tissues of seronegative pregnant gilts, cross the placenta, and cause fetal death and mummification.

Bioaccumulation of methyl parathion and its toxicology in several species of the freshwater community in Ignacio Ramirez dam in Mexico

Environmental contamination by pesticides, including the presence of chemical residues in aquatic wildlife, is a widespread ecological problem. Methyl parathion (MP), a widely used organophosphorate insecticide, is a potent neurotoxic in both vertebrates and invertebrates. The effect of a subchronic exposure to MP in aquatic organisms was evaluated in a natural ecosystem measuring acetyl cholinesterase (AChE) and gamma glutamil transpeptidase (GGT) activity. Two samples were conducted. Physicochemical characterization was done at each sampling time and organisms were collected. MP and metabolite 4-nitrophenol (4-NP) concentrations were measured in water sediment and organisms. The major differences in physical features between season were an increase of turbidity and salinity and depletion of dissolved oxygen in the rainy season. MP and 4-NP are bioconcentrated in organisms in response to environmental stress. MP concentration was measured in different size/age and reproductive stages separately. A significant concentration in reproductive tissues (plants)/unborn progeny (animals) was always found, and this can affect egg viability. The metabolite 4-NP is bioaccumulated and is toxic because it causes an increase of AChE activity. GGT activity was higher than that in controls. The increase in enzymatic activity provides a detoxification mechanism from chronic sublethal exposure, when hepatic glutation depletion occurs, and may be an indicator of liver damage.

Determination of chlorophenols in drinking water with high resolution gas chromatography-tandem mass spectrometry

A new method for the determination of sub-ppb levels of chlorophenols in drinking water by use of GC-MS-MS is proposed. Monitoring of these analytes for assurance of compliance with legally allowed limits can readily be accomplished by extraction as acetylated chlorophenols from low sample volumes (10 ml). Much lower detection limits can be achieved by preconcentrating 11 of sample using graphitized carbon cartridges for solid extraction. Appropriate selection of parent ions and fragmentation conditions ensures not only a high sensitivity, but also clean product ion spectra that allow positive identification of every species considered (polychlorophenol isomers included).