Components of (co)variance of the days open in Siboney dairy cows

The records of 63,406 calvings of Siboney dairy cows (5/8 Holstein 3/8 Cuban Zebu) were used to estimate the components of covariance of the days open (DO). Five models were used: of repeatability; univariate; bivariate; of random regression with Legendre polynomials and the parity number as predicting variable; and a model of random regression with Legendre polynomials and heterogeneity of the residual variance. The heritability obtained with the univariate model was 0.09 in the first calving and decreased to 0.05 in the fifth. A higher estimate of heritability (0.12) was obtained with the repeatability model. When the model of random regression with heterogeneity of the residual variance was used, the heritability was higher than the values estimated with the previous models. The genetic correlations among the DO in different calvings, estimated with the models of random regression with and without heterogeneity of the residual variance, were close to 1.0. It is concluded that the estimates of heritability increased with the use of the random regression models. The genetic correlations among the DO of different calvings indicated that in the first three, the DO are regulated for the most part by the same genes.

Intrapleural fibrinolysis with streptokinase as an adjunctive treatment in hemothorax and empyema: a multicenter trial

To test the efficacy of intrapleural fibrinolytic therapy in patients with loculated pleural effusions, we conducted an open, prospective, and multicenter trial among five hospitals in Mexico. We enrolled patients with hemothorax or empyema, clotted and/or loculated, that was not resolved through conventional pleural drainage with chest tube and antibiotics in patients with empyema. All patients received repeated doses of 250,000 IU of streptokinase through chest tube. Effectiveness criteria were before and after intrapleural streptokinase (IPSK) drainage, and poststreptokinase radiographic and respiratory function test improvement. Forty-eight patients were studied; there were 30 patients with empyemas, 14 with hemothorax, and 4 patients with malignant pleural effusions without lung trapping. Successful fibrinolysis was obtained in 44 patients, with complete resolution of the pleural collection and adequate radiologic and spirometric improvement. In three of four patients with multiloculated malignant hemothorax with high-yielding pleural drainage, IPSK allowed successful lysis of loci and an adequate pleurodesis was achieved. Only four patients required surgical treatment. The overall success rate in our series was 92%, similar to previous reports. The results in this first prospective and multicentric trial suggest that intrapleural fibrinolysis is an effective and safe adjunctive treatment in patients with heterogeneous pleural coagulated and loculated collections to restore the pulmonary function assessed by respiratory function tests and can obviate surgery in most cases.

Pulmonary arterial hypertension and cor pulmonale associated with chronic domestic woodsmoke inhalation

We describe the clinical, radiologic, functional, and pulmonary hemodynamic characteristics of a group of 30 nonsmoking patients with a lung disease that may be related to intense, long-standing indoor wood-smoke exposure. The endoscopic and some of the pathologic findings are also presented. Intense and prolonged wood-smoke inhalation may produce a chronic pulmonary disease that is similar in many aspects to other forms of inorganic dust-exposure interstitial lung disease. It affects mostly country women in their 60s, and severe dyspnea and cough are the outstanding complaints. The chest roentgenograms show a diffuse, bilateral, reticulonodular pattern, combined with normalized or hyperinflated lungs, as well as indirect signs of pulmonary arterial hypertension (PAH). On the pulmonary function test the patients show a mixed restrictive-obstructive pattern with severe hypoxemia and variable degrees of hypercapnia. Endoscopic findings are those of acute and chronic bronchitis and intense anthracotic staining of the airways appears to be quite characteristic. Fibrous and inflammatory focal thickening of the alveolar septa as well as diffuse parenchymal anthracotic deposits are the most prominent pathologic findings, although inflammatory changes of the bronchial epithelium are also present. The patients had severe PAH in which, as in other chronic lung diseases, chronic alveolar hypoxia may play the main pathogenetic role. However, PAH in wood-smoke inhalation-associated lung disease (WSIALD) appears to be more severe than in other forms of interstitial lung disease and tobacco-related COPD. The patients we studied are a selected group and they may represent one end of the spectrum of the WSIALD.

Organochlorine pesticide residues in human milk samples from Comarca Lagunera, Mexico, 1976

Milk samples were obtained from 15 nursing mothers in the agricultural region of Comarca Lagunera, Mexico, and were analyzed for organochlorine pesticide residues. Nine different types of residues were found. Of these, p,p'-DDE, p,p'-DDT, and beta-BHC occurred most frequently. All samples had concentrations of DDT-derived compounds higher than the practical limit recommended by the U.N. Food and Agriculture Organization/World Health Organization for DDT in cows' milk. Residues of other chlorinated hydrocarbons were present at levels similar to those found in human milk in other developing countries.

Organochlorine pesticide residues in human adipose tissue in Mexico: results of a preliminary study in three Mexican cities

The results of a preliminary search to determine the levels of organochlorine pesticide residues in the adipose tissue of the inhabitants of three Mexican cities of different socioeconomic characteristics are described herein. The concentrations and percent occurrence of nine compounds found are reported. In general, the samples analyzed had a large number of different organochlorine residues per sample. The results indicate that the inhabitants have been heavily exposed to 1,1,1-trichloro-2,2-bis (p-chloro-phenyl) ethane (DDT), and to a lesser degree, to 1,2,3,4,5,6,-hexachlorocyclohexane (BHC). The mean concentration of 1,1-dichloro-2,2-bis (p-chlorophenyl) ethylene (DDE) in one of the groups (18.36 ppm lipid basis) was one of the highest reported in the literature. It is also noteworthy that DDT was found in only 63, 89, and 55% of the samples from the three cities.