Approaching PM(2.5) and PM(2.5-10) source apportionment by mass balance analysis, principal component analysis and particle size distribution

A chemical characterization was carried out for PM(2.5) and PM(2.5-10) samples collected in a suburban area and the concentrations of 12 elements were determined in 8 size segregated fractions using a Berner Impactor. Two main objectives were proposed in this work: 1) to test for closure among chemical and gravimetric measurements of PM(2.5) and PM(2.5-10) and 2) evaluate the performance of Multilinear Regression Analysis (MLRA) and Mass Balance Analysis (MBA) in the determination of source contribution to Particulate Matter (PM) concentrations. The fraction unaccounted for by chemical analysis comprised on average 17% and 34% of gravimetric PM(2.5) and PM(2.5-10), respectively. The lack of closure in PM(2.5) and PM(2.5-10) mass (i.e., constituent concentrations not adding up to gravimetrically measured) could partly result from the presence of water associated with particles and errors in the estimation of unmeasured species. MLRA and MBA showed very similar results for the temporal variation of the source contributions. However, quantitatively important discrepancies could be observed, principally due to the lack of mass closure in PM(2.5) and PM(2.5-10). Both methods indicated that the major PM(2.5) aerosol mass contributors included secondary aerosol and vehicle exhaust. In the coarse fraction, marine and mineral aerosol contributions were predominant.

Description of microscopic lesions of vestibular folds of autopsied adults and their relationship with cause of death and underlying disease

The increase in invasive methods currently applied to diagnosis airway upper tract infection leads to a possible increase in vestibular folds (VF) lesions. Besides, VF importance in the prevention of the organism against infection pathogens had been stressed and few studies had addressed the microscopic lesions of the VF in autopsied patients because there is no routine VF examination in the postmortem exam.

Aim

The aim of this study is morphological microscopic analyses of the VF from autopsied patients and its correlation with basic disease and cause of death.

Study design

transversal cohort.

Material and Method

We studied 82 larynges collected during the autopsy exam and performed the Hematoxylin -eosin method for morphological analyses.

Results

From the 82 vestibular folds analyzed we observe that 42 (51%) showed an inflammatory reaction. In fifteen (18.3%) vestibular folds we found lymphoid follicular hyperplasia, in eleven (13.4%) diffuse inflammatory infiltrate and in sixteen (19.5%) acute inflammatory reactions. Circulatory diseases were the most frequently underlying diseases found, 31 (37.8%) and from these 20 (67.8%) presented associated vestibular folds inflammatory reaction. The infection diseases were the most frequently cause of death among the patients with inflammatory reaction of the VF.

Conclusion

Besides the anatomic function, VF seem to have a immunological function preventing lower airway infections. Our study demonstrated inflammatory PV reactions in patients with infections diseases as cause of death; this finding could be a consequence of the sepses that leads the patient to death or a different way used by the organism to prevent infection.

Gravimetric and chemical features of airborne PM 10 AND PM 2.5 in mainland Portugal

This paper describes concentration amounts of arsenic (As), particulate mercury (Hg), nickel (Ni) and lead (Pb) in PM(10) and PM(2.5), collected since 1993 by the Technological and Nuclear Institute (ITN) at different locations in mainland Portugal, featuring urban, industrial and rural environments, and a control as well. Most results were obtained in the vicinity of coal- and oil-fired power plants. Airborne mass concentrations were determined by gravimetry. As and Hg concentrations were obtained through instrumental neutron activation analysis (INAA), and Ni and Pb concentrations through proton-induced X-ray emission (PIXE). Comparison with the EU (European Union) and the US EPA (United States Environmental Protection Agency) directives for Ambient Air has been carried out, even though the sampling protocols herein--set within the framework of ITN's R&D projects and/or monitoring contracts--were not consistent with the former regulations. Taking this into account, 1) the EU daily limit for PM(10) was exceeded a few times in all sites except the control, even if the number of times was still inferior to the allowed one; 2) the EU annual mean for PM(10) was exceeded at one site; 3) the EPA daily limit for PM(2.5) was exceeded one time at three sites; 4) the EPA annual mean for PM(2.5) was exceeded at most sites; 5) the inner-Lisbon site approached or exceeded the legislated PMs; 6) Pb levels stayed far below the EU limit value; and 7) concentrations of As, Ni and Hg were also far less than the reference values adopted by EU. In every location, Ni appeared more concentrated in PM(2.5) than in coarser particles, and its levels were not that different from site to site, excluding the control. The highest As and Hg concentrations were found in the neighbourhood of the coal-fired, utility power plants. The results may be viewed as a "worst-case scenario" of atmospheric pollution, since they have been obtained in busy urban-industrial areas and/or near major power-generation and waste-incineration facilities.

Thickening of the amnion basement membrane and its relationship to placental inflammatory lesions and fetal and maternal disorders

OBJECTIVE

The aim of this study is the morphological and morphometric analysis of the basement membrane amniotic epithelium of the chorionic plate to establish possible correlation between the basement membrane amniotic epithelium thickening and maternal and fetal disorders.

STUDY DESIGN

Ninety-one placentas of infants delivered in Medical Hospital School were studied with hematoxylin-eosin (H&E) and Periodic Acid Schiff (PAS) methods, morphometric and ultrastructural analysis.

RESULTS

Of the 91 placentas analyzed, 17 (18.6%) were normal with regard to placental morphology, fetal and maternal history. Basement membrane amniotic epithelium thickening was significantly greater in the cases associated with chorioamnionitis (P=0.013), villitis (P=0.040), maternal hypertension syndromes during pregnancy (P=0.027) and stillborn (P=0.040) babies. The electron microscopic examination of the basement membrane amniotic epithelium identified a structural alteration and edema of the dense lamina.

CONCLUSION

Thickening of the basement membrane amniotic epithelium was associated with morphologic placental abnormalities and/or fetal or maternal disorders. Thickening of the basement membrane amniotic epithelium was identified away from the site of placental inflammation, possibly being a consequence of cytokines, supporting more than a local effect. This could be a new insight into the pathogenesis of fetal and maternal complications associated with inflammatory placental lesions.

Organomercurial removal from vaccine production wastewaters in a supported liquid membrane bioreactor

Vaccine production effluents are strongly polluted with thiomersal, a highly toxic organomercurial compound, for which there is presently no remediation technology available. This work describes a new remediation process based on the extraction of thiomersal from the wastewater to a biological compartment, where it is degraded by a microbial strain. The selective extraction of thiomersal is achieved by using an ionic liquid immobilized in a porous membrane. In the biological compartment, thiomersal is degraded to metallic mercury, under aerobic conditions, by a Pseudomonas putida strain. The utilization of ionic liquids in supported liquid membranes for thiomersal transport, and the kinetics of thiomersal biodegradation by a Pseudomonas putida strain are presented and discussed.

An evaluation of olive-tree bark for the biological monitoring of airborne trace-elements at ground level

There is a need to start looking into the possibility of tree bark for biomonitoring. Bark from olive trees (Olea europaea Linn.) has been collected over an area in northwestern Portugal, featuring a blend of rural lands, industrial towns and coastal environments. Samples were analysed through INAA and PIXE for their elemental contents. Results from both techniques were reconciled and then compared with an extensive database on 46 trace elements in Parmelia spp. thalli from the same sites and mostly from the very bark substrates. Distribution-free, nonparametric statistics show that, despite signal magnitude, variation patterns of bark and lichen concentrations follow one another in a most significant way. Selected elements in bark also correlate to a superior extent. As far as this investigation goes, there is no reason whatsoever for discarding bark as an alternative to lower epiphytes.

Calibration of lichen transplants considering faint memory effects

Biomonitoring, among other purposes, can be used as a tool to study the dispersion of trace elements through the atmosphere and back to the earth's surface again. In this sense it has been used for more than 20 years now. Yet, the calibration of biomonitors elemental contents against other atmospheric element dispersion variables like deposition or airborne concentration is still an open subject. The knowledge of a calibration nevertheless represents a qualitative improvement upon the use of biomonitors. Biomonitors elemental contents are usually assumed to depend in a linear way on the average values of atmospheric element dispersion variables, thus a linear regression is assumed to provide a good calibration. In this work: the element dispersion variables like deposition or airborne concentration will be referred in general as availability variables due to reasons that will be clarified; an uptake experiment using transplants of lichen Parmelia sulcata carried out in Portugal during a 2-year period (1994/1996) is described; and new concepts and calibration methods are presented. Lichen and aerosol samples were analysed by nuclear analytical techniques PIXE and INAA, and total deposition dry residue samples were analysed by ICP-MS. A database of roughly 70,000 values was thus created and biomonitor calibration carried out considering that biomonitors are not mechanical instruments but that they rather describe their exposure with a non-perfect memory. Data shows that surveying lichens four times within 1 year, with a period of 3 months in between sampling campaigns, allows the recovery of availability mean, maxima and standard deviation for many elements.

A comparative study for results obtained using biomonitors and PM10 collectors in Sado Estuary

In 1996 a program was started, financed by the Environmental Ministry of Portugal and IAEA, aiming to study the inorganic atmospheric pollutant dispersion in Sado Estuary. Gent PM10 air samplers were used for air particulate matter sampling. Three sampling sites were chosen, forming a triangle around the fuel power station of Setúbal. Transplants of Parmelia sulcata Taylor were suspended in nylon bags within a rectangle 15 km wide and 25 km long on a 2.5 x 2.5 km grid. Two sets of four transplants were hung in each of the 47 locations, one set facing the wind and the other set opposing the wind. The transplants were suspended in December 1997 for a 1-year period; every 3 months, one transplant of each set was collected. Both lichen transplants and PM10 filters were analysed by INAA and PIXE. A comparative study of results obtained for the two sampling procedures is presented in this work.

In situ corrosion control in industrial water systems

The main objective of this study was to evaluate the efficacy of a biocide and a corrosion inhibitor against the corrosion of a circulating pipe in a cooling tower. Isothiazolone was tested as the industrial biocide. The results showed that the biocide by itself or combined with a dispersant was not efficient to control corrosion in the industrial system. Corrosion rates of 0.324 mm/year were recorded in both the presence and absence of the biocide. Corrosion control was successfully accomplished by using a corrosion inhibitor. In the latter case the maximum corrosion rate of 0.024 mm/year were obtained.

Mechanism of charged pollutants removal in an ion exchange membrane bioreactor: drinking water denitrification

The mechanism of anionic pollutant removal in an ion exchange membrane bioreactor (IEMB) was studied for drinking water denitrification. This hybrid process combines continuous ion exchange transport (Donnan dialysis) of nitrate and its simultaneous bioreduction to gaseous nitrogen. A nonporous mono-anion permselective membrane precludes direct contact between the polluted water and the denitrifying culture and prevents secondary pollution of the treated water with dissolved nutrients and metabolic products. Complete denitrification may be achieved without accumulation of NO3(-) and NO2(-) ions in the biocompartment. Focus was given to the effect of the concentration of co-ions, counterions, and ethanol on the IEMB performance. The nitrate overall mass transfer coefficient in this hybrid process was found to be 2.8 times higher compared to that in a pure Donnan dialysis process without denitrification. Furthermore, by adjusting the ratio of co-ions between the biocompartment and the polluted water compartment, the magnitude and direction of each individual anion flux can be easily regulated, allowing for flexible process operation and control. Synthetic groundwater containing 135-350 mg NO3(-) L(-1) was treated in the IEMB system. A surface denitrification rate of 33 g NO3(-) per square meter of membrane per day was obtained at a nitrate loading rate of 360 g NO3(-) m(-3)d(-1), resulting in a nitrate removal efficiency of 85%.

Magnesium deficiency improves glucose homeostasis in the rat: studies in vivo and in isolated islets in vitro

The serum mineral levels, glucose disappearance rate (kg), total area under the glucose (DeltaG) and insulin (DeltaI) curves, and static insulin secretion were compared among rats fed a Mg-deficient diet for 6 (DF-6) or 11 (DF-11) weeks, and rats fed a control diet for the same periods (CO-6 and CO-11 groups). No change in glucose homeostasis was observed among DF-6, CO-6 and CO-11 rats. DF-11 rats showed an elevated kg and a reduced DeltaG and DeltaI. For evaluating the effect of supplementation, rats fed a control or Mg-deficient diet for 6 weeks were then fed a Mg- supplemented diet for 5 weeks (SCO and SDF groups respectively). The serum Mg levels in SDF rats were similar to those in CO-11 and SCO rats, but higher than in the DF-11 group. SDF rats showed similar kg, DeltaG and DeltaI compared with the CO-11 and SCO groups. However, a significantly lower kg and higher DeltaG and DeltaI were observed in SDF compared with DF-11 rats. Basal and 8.3 mmol glucose/l-stimulated insulin secretion by islets from DF-11 rats were higher than by islets from CO-11 rats. These results indicate that moderate Mg depletion for a long period may increase the secretion and sensitivity to insulin, while Mg supplementation in formerly Mg-deficient rats may prevent the increase in sensitivity and secretion of insulin.

Two-dimensional fluorometry coupled with artificial neural networks: a novel method for on-line monitoring of complex biological processes

The use of two-dimensional scanning fluorometry as an on-line, noninvasive, in situ bioreactor monitoring technique is extended to complex bioprocesses using mixed cultures, with particular attention to biofilm systems. Using the example of spectra subtraction, it is demonstrated that established methods for fluorescence data analysis have a limited capability of utilizing overall fluorometric information. Artificial neural networks (ANNs) are introduced as a novel nonlinear and nonmechanistic technique for interpreting the highly complex fluorescence maps. It is shown that ANNs are able to infer process performance parameters in a pattern recognition approach, based on the entire fluorescence "fingerprint" of the biological system. The studies were carried out using an extractive membrane bioreactor (EMB) for the degradation of chlorinated organic compounds, operating with mixed cultures. Model pollutants em- ployed were 1,2-dichloroethane, 3-chloro-4-methylaniline, and p-toluidine.

Magnesium deficiency modulates the insulin signaling pathway in liver but not muscle of rats

Altered insulin secretion and sensitivity have been observed in Mg-deficient animals. However, the effects of Mg deficiency and supplementation on intracellular signaling events triggered by insulin are unknown. Therefore, we studied the early steps of insulin action in muscle and liver of rats fed Mg-deficient (DF-6, DF-11) or control (CO-6, CO-11) diets for 6 or 11 wk, respectively, and Mg-deficient or control diets for 6 wk, followed by Mg supplementation for 5 wk (SDF and SCO groups, respectively). There were no differences in the glucose disappearance rate (K(itt)) or insulin signaling between CO-6 and DF-6 rats. Between the two groups of rats fed for 11 wk, the DF-11 group had a significantly greater K(itt). SDF and SCO rats had K(itt) that did not differ from CO-11 rats, but that were significantly lower than in DF-11 rats. In the latter rats, insulin receptor and insulin receptor substrate-1 protein and phosphorylation levels were elevated in liver and there was a greater association between the insulin receptor substrate-1 and p85 subunit of phosphatidyl-inositol 3-kinase compared with CO-11 rats. There were no differences in the early steps of insulin action in SDF and control rats. These results suggest that the normal insulin sensitivity maintained by Mg supplementation and the increased insulin sensitivity produced by a long period of Mg deprivation may result, at least in part, from alterations in or maintenance of the early molecular steps of insulin action in hepatic tissue.

[Occurrence of encephalic and cardiac cysticercosis (Cysticercus cellulosae) in necropsy]

OBJECTIVE

To review the incidence and pathologic findings of cysticercosis diagnosed at autopsies, with emphasis on the most common organs affected.

METHODS

Reports of 1.596 autopsies performed between 1974 and 1997 at a school hospital in Uberaba, MG, Brazil were studied. The following data were obtained: age, sex, ethnic group, body mass index, and the site of the cysticercosis.

RESULTS

The study found diagnosis of cysticercosis in 53 autopsies (3.3%). The average age of patients with cysticercosis was 50 (range: 15 to 86 years); 62.3% were male, and 64.1% Caucasian. The most affected organs were: brain (79.2%), heart (22.6%), skeletal muscle (11.3%), and other organs (5.7%). No statistical differences were found comparing age, gender, ethnic group, and body mass index of the affected and the non-affected patients. In two cases of neurocysticercosis the lesions were located in the ventromedial nucleus of the hypothalamus.

CONCLUSION

Both the overall incidence of cysticercosis and the incidence of cardiac cysticercosis were greater in the study than in other autopsy series from the same geographic areas. In two cases there was an association between hypothalamic cysticercosis and obesity

Glucose metabolism and kinetics of phosphorus removal by the fermentative bacterium Microlunatus phosphovorus

Phosphorus and carbon metabolism in Microlunatus phosphovorus was investigated by using a batch reactor to study the kinetics of uptake and release of extracellular compounds, in combination with (31)P and (13)C nuclear magnetic resonance (NMR) to characterize intracellular pools and to trace the fate of carbon substrates through the anaerobic and aerobic cycles. The organism was subjected to repetitive anaerobic and aerobic cycles to induce phosphorus release and uptake in a sequential batch reactor; an ultrafiltration membrane module was required since cell suspensions did not sediment. M. phosphovorus fermented glucose to acetate via an Embden-Meyerhof pathway but was unable to grow under anaerobic conditions. A remarkable time shift was observed between the uptake of glucose and excretion of acetate, resulting in an intracellular accumulation of acetate. The acetate produced was oxidized in the subsequent aerobic stage. Very high phosphorus release and uptake rates were measured, 3.34 mmol g of cell(-1) h(-1) and 1.56 mmol g of cell(-1) h(-1), respectively, values only comparable with those determined in activated sludge. In the aerobic period, growth was strictly dependent on the availability of external phosphate. Natural abundance (13)C NMR showed the presence of reserves of glutamate and trehalose in cell suspensions. Unexpectedly, [1-(13)C]glucose was not significantly channeled to the synthesis of internal reserves in the anaerobic phase, and acetate was not during the aerobic stage, although the glutamate pool became labeled via the exchange with intermediates of the tricarboxylic acid cycle at the level of glutamate dehydrogenase. The intracellular pool of glutamate increased under anaerobic conditions and decreased during the aerobic period. The contribution of M. phosphovorus for phosphorus removal in wastewater treatment plants is discussed on the basis of the metabolic features disclosed by this study.

Distribution in Portugal of some pollutants in the lichen Parmelia sulcata

During the months of July and August 1993 a lichen (Parmelia sulcata Taylor) collection campaign was held in Portugal where samples were obtained from olive tree bark at 228 sites, following a grid of 10 x 10 km along the Atlantic coast and 50 x 50 km in the interior of the country. The samples were analysed by instrumental neutron activation analysis and proton induced X-ray emission techniques. Concentration data patterns for the pollutants As, Cr, Hg, Ni, Pb, S, Sb, Se, and V were obtained for the whole country surface by making use of an extinction rule of 1/r(3), preventing any cut-off distance from being artificially introduced. Some pollution sources were identified: (1) oil-powered plants on the Lisbon-Setúbal axis (V, Ni), (2) coal-power plants in Porto and Sines (S, Se), (3) traffic in the northern area and the Lisbon-Setúbal axis (Pb), (4) a chemical industry south of Porto (Hg, As), and (5) soil influence (Cr, Sb). Arsenic and chromium results largely exceed, in a few areas, the concentrations acceptable to plants, and in a few spots also Hg, Ni, and Pb data.

Environmental assessment in an industrial area of Portugal

The region of Lisbon and south of Lisbon (Sado estuary) is densely industrialized, and, therefore, air pollution should be studied in a more detailed scale there. The topography of the Sado estuary region and the predominant wind direction from the northwest contribute to the influence in this region of the industries located in the north. The region selected includes a fuel-fired power station. Transplants of the lichen Parmelia sulcata Taylor were suspended in nylon bags within a rectangle 15 km wide and 25 km long on a grid 2.5 km x 2.5 km, centered in the power station. In each of the 47 sites, 2 sets of 4 transplants each were hung. Care was taken (1) in covering the two sets with a polyethylene roof to prevent leaching of elements in the lichen, (2) in building a hanging system that could rotate according to the wind direction, and (3) in orienting one set toward the wind and the other set opposite the wind. For a 1-yr period and every 3 mo, one transplant of each set is collected. In this work, the results of the first campaign (after 3 mo suspension) obtained by instrumental neutron activation analysis and proton-induced X-ray emission are shown. Some elemental contents are mapped and discussed.

Protein deficiency and nutritional recovery modulate insulin secretion and the early steps of insulin action in rats

Maternal malnutrition was shown to affect early growth and leads to permanent alterations in insulin secretion and sensitivity of offspring. In addition, epidemiological studies showed an association between low birth weight and glucose intolerance in adult life. To understand these interactions better, we investigated the insulin secretion by isolated islets and the early events related to insulin action in the hind-limb muscle of adult rats fed a diet of 17% protein (control) or 6% protein [low (LP) protein] during fetal life, suckling and after weaning, and in rats receiving 6% protein during fetal life and suckling followed by a 17% protein diet after weaning (recovered). The basal and maximal insulin secretion by islets from rats fed LP diet and the basal release by islets from recovered rats were significantly lower than that of control rats. The dose-response curves to glucose of islets from LP and recovered groups were shifted to the right compared to control islets, with the half-maximal response (EC50) occurring at 16.9 +/- 1.3, 12.4 +/- 0.5 and 8.4 +/- 0.1 mmol/L, respectively. The levels of insulin receptor, as well as insulin receptor substrate-1 and phosphorylation and the association between insulin receptor substrate-1 and phosphatidylinositol 3-kinase were greater in rats fed a LP diet than in control rats. In recovered rats, these variables were not significantly different from those of the other two groups. These results suggest that glucose homeostasis is maintained in LP and recovered rats by an increased sensitivity to insulin as a result of alterations in the early steps of the insulin signal transduction pathway.

[Candidiasis in kidney transplant patients]

The medical records of 620 patients submitted to renal transplant from February 1968 to February 1995 were surveyed for Candida infection. Of these, 87 presented 107 episodes of candidiasis. In 42.9% the infection appeared up to 6 months after the transplant. The most frequent involved sites were: urinary tract, respiratory tract, and gastrointestinal tract. The most frequent etiological agents were: C. albicans, C. tropicalis and C. glabrata. Most urinary tract infections occurred in the first 6 months (61.7%) and manifested clinically as a bacterial infection. In the respiratory tract infections were characterized by isolation of the agent in sputum. In the gastrointestinal infections, 9/16 episodes were esophageal. There were 3 deaths directly related to Candidiasis (one pulmonary and 2 disseminated cases). In the urinary tract, and respiratory tract infections there was association of candidiasis with previous antibiotic treatment (76% and 67%, respectively), and with concomitant bacterial infections (34% and 64%, respectively). The overall prevalence of Candida infections was 14.5%. The predominant location was in the urinary tract (51.0%), followed by the respiratory (26.0%) and gastrointestinal tract (15.0%), with a high rate of association with previous antibiotic treatment and bacterial infections.

Use of ciprofloxacin as a prophylactic agent in urinary tract infections in renal transplant recipients

The most common form of bacterial infection in renal transplant recipients is urinary tract infection (UTI), and some studies have shown that prophylaxis can reduce this incidence. In the present investigation we evaluated 80 patients submitted to renal transplantation at the Renal Transplant Unit of the University Hospital of Ribeirao Preto, SP. The study was prospective, double blind and randomized. The patients were divided into two groups, one receiving placebo and the other ciprofloxacin at the dose of 250 mg twice a day for the first 10 d and 250 mg/d for 6 months after transplantation. Of the 41 patients who received ciprofloxacin 28 completed the study, and of the 39 patients who received placebo 30 completed the study. The largest number of UTI occurred in the placebo group, with a significant difference from the ciprofloxacin group during the first month after surgery (p < 0.05). In the group treated with ciprofloxacin, only 6/40 patients (15%) developed UTI, as opposed to 19/39 (48.7%) for the placebo group. The total number of infectious episodes was higher in the placebo group (26) than in the ciprofloxacin group (12). The medication was well tolerated throughout the study period.

Relationship between Chagas' disease immunoreactivity in pericardial fluid and survival of children

Pericardial fluid (PF) obtained at autopsy has been used for the study of fluid pericardium proteins in noninfectious and infectious diseases such as Chagas' disease. The aim of the present study was to determine the immunoreactivity to Chagas' disease in PF obtained at autopsy from children in an endemic area. A total of 251 autopsy records were surveyed from the files of the Medical School of Uberaba, Brazil, of children ranging in age from stillborn to 14 yr who had died between 1968 and 1992. The reactions for Chagas' disease (immunofluorescence, complement fixation, and hemagglutination) applied to PF were recorded. Thirty-four children (13.5%) showed positive reactions to Chagas' disease. The frequency of immunoreactivity was significantly related to age-group distribution (chi 2 = 13.4; P < 0.005). Children with negative PF tests who had died between 1 and 60 days of age presented a median survival time of 13 days; positive children presented a median survival time of 4 days (Z = 2.1; P = 0.02). These data indicate that the prevalence of Chagas' disease is high among pregnant women in southern Brazil. In addition, they also suggest that "antitrypanosome antibodies" detected in PF may be 1 of the indicators of age of infant death and may possibly play a role in the course of the disease in children born from mothers with Chagas' disease.