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The present study analyzes the frequency of chromosomal aberrations found in rodents living in a polluted area near the Rimac river (Casapalca, minery zone) at 120 Km of Lima, compared to that observed in a non-polluted area in the Department of Lima, Perú. The species analyzed were: Phyllotis andium, P. darwini and Akodon boliviensis. The rodents were captured alive and bone marrow was processed the same day of capture to obtain metaphases. The results showed significant differences (p < 0.05) in the frequency of chromosomal aberrations in the rodents of the exposed area (2.46% of cells) vs those of the control area (0.82% of cells). These results are consistent with the hypothesis that heavy metals and pesticides present in the Rimac river may increment the frequency of chromosomal aberrations in rodents living near that river.

Background: Neonatal respiratory distress syndrome (RDS) is caused by a deficiency of pulmonary surfactant. Alveolar collapse and obstruction of conducting airways leads to mismatch of ventilation and perfusion and profound hypoxemia. We postulated that surfactant deficiency could alter the properties of respiratory mucus in such a way that it would be poorly cleared from airways and promote airway luminal obstruction and that these changes might be reversed by the exogenous administration of a synthetic surfactant preparation., Methods: Respiratory mucus coating an endotracheal tube (ETT) or suction catheter was collected from 14 neonates (gestational age, 24 to 36 weeks; birth weight, 600 to 2,400 g) with RDS who required tracheal intubation and ventilation. Eight of these neonates received 5 ml/kg of an intratracheal artificial surfactant preparation (Exosurf), given between 2 and 10 h of age and six neonates received 5 ml/kg of air. Mucus viscoelasticity, hydration (percentage of solid composition of mucus), and mucociliary clearability (NFPTR) were measured for each specimen., Results: The total volume of mucus collected from the surfactant-treated and control infants was similar, but mucus hydration was significantly less in babies with RDS who did not receive Exosurf (percentage of solid composition of mucus 18.7 vs 11.4; p = 0.013). Ciliary transportability was also less in the untreated babies (NFPTR 0.39 vs 0.86; p = 0.018) and this mucus was more rigid (increased viscoelasticity: log G* 1 rad/s 2.28 vs 1.50; p = 0.0001)., Conclusions: These data suggest that airway obstruction in RDS may be due, in part, to abnormal mucus properties and impaired ciliary transport. Surfactant therapy appears to improve mucus clearability. Exogenously administered surfactant may also be beneficial for the treatment of other selected respiratory conditions associated with impaired mucus clearance.

We compared the physical and transport properties of tracheal mucus collected from 16 asymptomatic smokers and from 18 nonsmokers. The smokers produced a larger volume of mucus (wet weight 18.6 versus 11.2 mg; p = 0.04) with a lower solids content (11.5 versus 16.3%; p = 0.02) and a lower modulus of rigidity (log G* 2.37 versus 2.62; p = 0.04). Although the smokers mucus had a 40% faster mucociliary transport rate on the frog palate (p = 0.04), the cough clearability was nearly identical to the mucus from nonsmokers. The differences are similar to those observed in rats or dogs chronically exposed to cigarette smoke. These data suggest both a quantitative and a qualitative difference in the composition of mucus from asymptomatic smokers. The increased volume of a watery mucus with increased mucociliary clearability may help to protect the airways from the injurious effects of inhaled smoke.

To better understand the frog palate model of mucociliary transport, we measured the transport rate of mucus (MTR) from the leopard frog, Rana pipiens, and from the bullfrog, R. catesbeiana, recorded the stability of the MTR over a period of hours and days and over the course of 1 yr, and measured the viscoelasticity, percent solid composition, and spinnability (filance) of mucus from both species. Bullfrog mucus was less rigid than leopard frog mucus (log G* at 1 rad/s 2.09 vs. 2.61; P less than 0.01) and had a higher viscosity-to-elasticity ratio (tan delta at 1 rad/s 0.36 vs. 0.26; P less than 0.05). It also had a lower solids content (8.71 vs. 13.72%; P = 0.02), and there was a trend to lower spinnability for bullfrog mucus (filance 26.7 vs. 33.5 mm). These data suggest that bullfrog mucus has viscoelastic properties similar to normal mammalian respiratory mucus and leopard frog mucus has viscoelasticity similar to sputum samples. MTR was significantly slower in the winter than in the summer months (17 vs. 30 mm/min; P less than 0.0001). Although the leopard frog palate could be used for at least 7 consecutive days without exhaustion, bullfrog palates could be used for only 5 days. Palates of either species could generally be tested for 6 h/day without a significant decrease in MTR. These data clarify some of the sources of variability in the use of this system and suggest methods of standardization.

Observations that mucus transport rates (MTR) are depressed in anesthetized animals and humans have led to speculation that general anesthesia depresses ciliary activity or adversely alters the physical properties of the respiratory mucus (RM). We investigated the possibility that anesthesia changes the physical properties of RM in such a way as to depress ciliary transport. We collected 33 samples of RM from the endotracheal tubes (ETTs) of 25 people aged 1 to 79 years undergoing elective surgery who had no clinical evidence of lung disease. We measured the rigidity, viscoelasticity, spinnability, and the percentage of solid composition of these specimens as well as the transport of the collected RM across the mucus-depleted frog palate. These physical properties were not significantly different from RM collected from awake volunteers using the bronchoscopy brush collection technique. Differences in spinnability, transportability, and solid content of paired mucus samples from the inside and outside of the ETTs are suggestive of altered RM hydration, but this requires further study. The decrease in MTR during general anesthesia is probably due to mechanisms other than alterations in the physical properties of mucus.

We collected the respiratory mucus coating the endotracheal tubes used during short surgical procedures in 27 patients with no clinical evidence of respiratory disease. Twelve were male and 15 were female, and they ranged from 1 to 64 yr of age (mean, 28.7 yr). The viscoelastic properties, frog palate transport rate, and percent solid composition were in the normal range reported for both canine and human mucus collected using the bronchoscopy brush technique. There were no significant differences noted between male and female patients, and there were no changes in mucus or transport properties seen with aging. Mucus was also collected separately from the inside of the tube exposed to constant gas flow (13 patients), and from the outside of the endotracheal tubes in 25 patients. Although there were no significant differences in viscoelastic properties between inside and outside mucus, there was a greater thread formation (filance, 45 versus 26 mm; p less than 0.005) and a higher percentage of solids in mucus from the inside of the endotracheal tube (15.9 versus 11.4%; p less than 0.05), which is compatible with reduced hydration. The duration of anesthesia ranged from 25 to 195 min (mean, 85 min). There was no effect of duration of anesthesia on any of the measured mucus properties. This technique for mucus collection allows us to study alterations in mucus properties in patients with and without pulmonary disease at the time of incidental surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Ten hypophysectomized and 10 normal female albino rats, 50-days-old, were kept for 5 days and treated with tritiated thymidine 1 hour before sacrifice of the animals. The animals were weighed and the histomorphology of the palate epithelium was studied including the thickness, cell density, and DNA labeling index. The hypophysectomized rats failed to gain weight after 5 days. The palatal epithelium showed a normal morphology indicating the hypophysectomy allowed for differentiation of squamous epithelium. There was a significant reduction in the thickness of the epithelium and a reduced cell density. This was attributed to a significant decrease in DNA synthesis. The epithelial cells were lost from the surface without adequate replacement due to an expected depression in mitotic activity. DNA synthesis may be depressed due to reduced ATP synthesis resulting from suboptimal glucose metabolism and depression in protein synthesis.

Granular cell tumors are benign lesions that usually appear in the skin, oral activity, and mucous membrane. Occasionally, they will appear in visceral organs, and cause signs and symptoms similar to those of other organ-related diseases. We studied a patient with granular cell tumors of the common bile duct whose clinical appearance mimicked that of cholecystitis with cholelithiasis. Recognition of granular cell tumors on frozen section will allow surgical resection with probable cure.

Seven cases of visceral leishmaniasis are reported, whose epidemiologic, clinical, laboratory, evolutive and therapeutical features are presented. Latest findings are described with reference to laboratory tests and new recent possibilities of therapy.

A clinical, histopathological, therapeutical and epidemiologic review of Ashy Dermatosis is done. This research has been taken from scientific publications, computers and personal communications. In twenty five years of scientific medical investigations it has not been determined its truth etiology , nor its therapeutic; this confirms it, as a new nosologic entity well defined. The epidemiologic researches are concludent that this is not a tropical disease exclusively, but one of all over the world. We hope to obtain more references on this dermatosis throughout the Sessions of Specialties of CILAD regarding this disease.

Studies were undertaken in 33 uremic patients with or without hypertension, 11 normal subjects, and 15 essential hypertensive patients to assess cardiac hemodynamics, plasma volume, extracellular fluid volume, and peripheral renin levels. Cardiac output and intraarterial blood pressure were measured and peripheral vascular resistance index calculated. These studies suggest that uremic hypertension with normal renin values and hypervolemia is hemodynamically sustained by an increase in peripheral resistance rather than by an increased cardiac output. The renin angiotensin system plays a secondary role as compared to overexpansion in the genesis of hypertension in normoreninemic uremic hypertension.

To determine the validity of endogenous creatinine clearance as a measure of glomerular filtration rate in patients with renal disease 308 simultaneous determinations of inulin clearance and endogenous creatinine clearance were reviewed and analysed. The ratio of creatinine clearance/inulin clearance increased progressively with the decline in inulin clearance, while the finding of a normal endogenous creatinine clearance masked a definite but mild decrease of glomerular filtration rate in 42% of the patients and a moderate decrease of glomerular filtration rate in 23%. This indicates that with declining glomerular filtration rates the endogenous creatinine clearance progressively overestimates actual glomerular filtration rates. Hence a single determination of creatinine clearance can be misleading as a screening measurement of glomerular filtration rate.