Organochlorine pesticide level differences among female inhabitants from Veracruz, Puebla and Tabasco, Mexico

Organochlorine pesticides have been used in Mexico in malaria control programs and against ectoparasites. The objective of this study was to compare the levels of organochlorine pesticides: HCB, α-β-γ-HCH, pp'-DDE, op'-DDT and pp'-DDT in adipose tissue of female inhabitants from three Mexican states: Veracruz, Puebla and Tabasco. Data analyses indicated higher β-HCH levels in Puebla inhabitants. When comparing the mean values of the pp'-DDE concentrations among the three states, no statistically significant differences were noted. A trend of increasing concentrations of op'-DDT from Veracruz to Puebla and Tabasco was observed. Significantly higher pp'-DDT concentrations in Veracruz as compared to Puebla and Tabasco were determined. Using factorial analysis of three age categories (>30, 31-50, <51) organochlorine pesticide concentrations increases with age of participants, indicating time of exposure as a principal factor of organochlorine pesticides accumulation in adipose tissue.

Levels of organochlorine pesticides residues in human adipose tissue, data from Tabasco, Mexico

The objective of this study was to determine the levels of organochlorine pesticides HCB, α-β-γ-HCH, p,p'-DDE, o,p'-DDT and p,p'-DDT in 150 adipose tissue of inhabitants of Tabasco, Mexico. The following pesticides were detected: p,p'-DDE in 100% of samples at mean 1.034 mg/kg; p,p'-DDT in 96.7% at mean 0.116 mg/kg; o,p'-DDT in 78.7% at mean 0.022 mg/kg and β-HCH in 58.0% at mean 0.049 mg/kg. The pooled sample was divided according to sex of donors (75 female and 75 male). Significantly higher levels of all organochlorine pesticides in females were found. The sample was divided into three age's ranges (15-28, 29-45 and 46-84 years). The mean and median levels of β-HCH, p,p'-DDE and Σ-DDT increase significantly (p < 0.05) from the first to the second and third group. The presence of organochlorine pesticide residues in Tabasco inhabitants is still observed, indicating sources of exposure to the pesticides.

Organochlorine pesticide residue levels in blood serum of inhabitants from Veracruz, Mexico

The objective of the present study was to monitor the levels of organochlorine pesticides HCB; α-, β-, γ-HCH; pp'DDE; op'DDT; and pp'DDT in blood serum of Veracruz, Mexico inhabitants. Organochlorine pesticides were analyzed in 150 blood serum samples that constituted that which remained after clinical analyses, using gas chromatography-electron-capture detection (GC-ECD). The results were expressed as milligrams per kilogram on fat basis and micrograms per liter on wet weight. Only the following pesticides were detected: p,p'-DDE was the major organochlorine component, detected in 100% of samples at mean 15.8 mg/kg and 8.4 μg/L; p,p'-DDT was presented in 41.3.% of monitored samples at mean 3.1 mg/kg and 1.4 μg/L; β-HCH was found in 48.6% of the samples at mean 4.9 mg/kg and 2.7 μg/L; op'DDT was determined to be in only 3.3% of monitored samples at mean 2.7 mg/kg and 1.4 μg/L. The pooled samples divided according to sex showed significant differences of β-HCH and pp'DDE concentrations in females. The samples grouped according to age presented the third tertile as more contaminated in both sexes, indicating age as a positively associated factor with serum organochlorine pesticide levels in Veracruz inhabitants.

Organochlorine pesticide levels in female adipose tissue from Puebla, Mexico

The objective of this study was to determine the levels of organochlorine pesticides HCB, α-β-γ-HCH, pp'DDE, op'DDT and pp'DDT in adipose tissue of females living in Puebla, Mexico. Organochlorine pesticides were analyzed in 75 abdominal adipose tissue samples taken during 2010 by autopsy at the Forensic Services of Puebla. The results were expressed as mg/kg on fat basis. In analyzed samples the following pesticides were detected: p,p'-DDE in 100% of samples at mean 1.464 mg/kg; p,p'-DDT in 96.0.% of samples at mean 0.105 mg/kg; op'DDT in 89.3% of monitored samples at mean 0.025 mg/kg and β-HCH in 94.7% of the samples at mean 0.108 mg/kg. To show if organochlorine pesticide levels in monitored female's adipose tissues are age dependant, the group was divided in three ages ranges (13-26, 26-57 and 57-96 years). The mean and median levels of all organochlorine pesticides increase significantly (p < 0.05) from the first to second and from the first to third group. At the same time, the increase of mean and medians levels from the second to third group were not statistically significant (p > 0.05). The present results compared to previous ones from 2008 indicates an increase in the concentrations during the 2010 study, but only the differences for pp'DDE and op'DDT were statistically significant. The 2010 group of females was older compared to the 2008 group. The presence of organochlorine pesticide residues is still observed, indicating uniform and permanent exposure to the pesticides by Puebla inhabitants.

Monitoring of organochlorine pesticide residue levels in adipose tissue of Veracruz, Mexico inhabitants

The objective of the present study was to monitor the levels of organochlorine pesticides HCB, α-β-γ-HCH, pp'DDE, op'DDT and pp'DDT in 150 adipose tissue samples of Veracruz, Mexico inhabitants. In analyzed samples, the following pesticides were detected: p,p'-DDE in 100% of the samples at mean 1.643 mg/kg; p,p'-DDT in 99.3.% of the samples at mean 0.227 mg/kg; β-HCH in 97.3% of the samples at mean 0.063 mg/kg; and op'DDT in 93.3% of the samples at mean 0.022 mg/kg. Comparing mean, median and geometric mean concentrations of organochlorine pesticides shows a decrease in values from mean to median and to geometric mean which points out a prevalence of lower concentrations among the total samples and the existence of occasional cases of extreme exposure expressed in range values. The pooled samples divided according to sex, showed only significant differences of pp'DDE median concentrations between sexes. The other organochlorine pesticides indicated no statistical differences between sexes, including the pp'DDE/pp'DDT ratio. The samples grouped according to age, showed that the third tertile was more contaminated for both sexes, indicating age as a positively associated factor with organochlorine pesticide levels in adipose tissue of Veracruz inhabitants. Comparing organochlorine pesticide levels between 2008 and 2010 years, a decreased tendency for β-HCH, pp'DDE, Σ-DDT and pp'DDE/pp'DDT ratio levels was observed.

Chronic stress impairs acoustic conditioning more than visual conditioning in rats: morphological and behavioural evidence

Chronic stress affects brain areas involved in learning and emotional responses. These alterations have been related with the development of cognitive deficits in major depression. The aim of this study was to determine the effect of chronic immobilization stress on the auditory and visual mesencephalic regions in the rat brain. We analyzed in Golgi preparations whether stress impairs the neuronal morphology of the inferior (auditory processing) and superior colliculi (visual processing). Afterward, we examined the effect of stress on acoustic and visual conditioning using an avoidance conditioning test. We found that stress induced dendritic atrophy in inferior colliculus neurons and did not affect neuronal morphology in the superior colliculus. Furthermore, stressed rats showed a stronger impairment in acoustic conditioning than in visual conditioning. Fifteen days post-stress the inferior colliculus neurons completely restored their dendritic structure, showing a high level of neural plasticity that is correlated with an improvement in acoustic learning. These results suggest that chronic stress has more deleterious effects in the subcortical auditory system than in the visual system and may affect the aversive system and fear-like behaviors. Our study opens a new approach to understand the pathophysiology of stress and stress-related disorders such as major depression.

[Umbilical and inguinal hernioplasty in cirrhotic patients]

The overall results of surgical treatment of abdominal wall hernias in patients with hepatic cirrhosis were assessed by a retrospective study in 41 cirrhotic patients. They underwent 22 umbilical and 22 inguinal herniorrhapies between 1982 and 1992. Sixteen patients were classified as Child-Pugh A, 16 as B and 9 as C. Clinical evidence of ascitis was documented in 19 patients. The operative mortality was 5% (two Child-Pugh C cases). Postoperative complications occurred in 10 patients, most of them related to the surgical wound. We recommend herniorraphy in symptomatic cirrhotic patients but with fairly good hepatic function.