[Air quality of premises and public health]

Indoor air quality is gaining increasing prominence as a public health problem in developed and developing countries. Its pollution brings about diseases (infectious, allergic, toxic, carcinogenic) or benign symptoms (without clear definition) grouped in the so-called Sick Building Syndrome. On the basis of 2 large surveys in air conditioned buildings the authors describe the main factors of this syndrome which is prominently observed in women and is multifactorial. The improvement of indoor air quality needs interaction among the diverse disciplines: architects, engineers, biologists and clinically oriented physicians.

[The anti-arrhythmia effect of carbamazepine in chagasic patients with advanced myocardial damage]

Oral administration of 600 mg/day of carbamazepine to 14 arrhythmic chagasic patients with advanced myocardial damage and no signs of congestive heart failure did not alter the frequency of ventricular extrasystoles, but reduced the total number of supraventricular ectopic beats in 7/14 patients and the episodes of complex ventricular arrhythmias in up to 43% of patients. This assessment was made from 24 hour continuous Holter recording during the course of this double-blind, placebo controlled, randomized crossover study. Serum levels of carbamazepine were also determined and found within therapeutic limits. Six patients complained of minor side effects. One patient presented with iatrogenic complete AV block, another case had proarrhythmic effect and one patient had to be withdrawn from the study because of gastric irritation. No instance of contractile depression was observed. Accordingly, carbamazepine is a therapeutic alternative for treatment of symptomatic complex ventricular or supraventricular arrhythmias in chronic chagasic patients without evidence of conduction system involvement or with intolerance to other antiarrhythmic drugs.

Anti-CD2-induced tyrosine phosphorylation of T cell polypeptides is independent of the PMA-induced modification of p56lck

The molecular basis for T cell activation involves the phosphorylation of of polypeptides at both serines and tyrosines. We find that with human peripheral T cells the serine phosphorylation of p56lck is independent of the more rapid tyrosine phosphorylation of other polypeptides via stimulation of the CD2 receptor with anti-CD2 (anti-T11(2) and anti-T11(3) mAb's). Triton X-100 soluble polypeptides were analyzed by Western blotting with the subsequent immunodetection by anti-phosphotyrosine or anti-lck antibodies. While polypeptides from resting T cells showed very low levels of endogenous tyrosine phosphorylation, incubation with anti-CD2 for periods as short as 30 sec resulted in the tyrosine phosphorylation of a 75-kDa polypeptide (p75). Polypeptide bands were also observed at 27 and 54 kDa, but these were artifacts from the reaction of anti-CD2 with the horse anti-mouse secondary antibody used in our detection system. Preincubation of T cells with phenylarsine oxide amplified the anti-CD2-induced tyrosine phosphorylation of the p75 and revealed additional phosphotyrosine polypeptides of 120, 100, and 33 kDa. The mitogenic combination of phorbol 12-myristate 13-acetate (PMA) with anti-CD2 changed neither the intensity nor the pattern of the tyrosine phosphorylation observed with anti-CD2 alone. The tyrosine phosphorylation of the p75 was not induced by concanavalin A (Con A) or PMA. While PMA alone failed to stimulate tyrosine phosphorylation above resting levels, PMA induced the nearly complete conversion of p56lck into p60lck (the lck-shift) at 30 min; no lck-shift was observed at 30 and 90 sec. Neither anti-CD2 nor Con A induced the lck-shift. Whereas PMA with either anti-CD2 or Con A was required for mitogenesis, only anti-CD2 led to tyrosine phosphorylation, and only PMA induced the lck-shift.

N-acetylcysteine enhances T cell functions and T cell growth in culture

N-Acetylcysteine (NAC) is highly nontoxic for peripheral blood T cells and immunostimulatory enhancing T cell functions such as mitogenesis, interleukin-2 (IL-2) production, and growth in culture. NAC has been proposed for the treatment of AIDS based on its inhibition of human immunodeficiency virus (HIV) replication in cultured cells. Therefore its effect on normal T cells from 10 young donors and one elderly donor has been investigated as a prelude to clinical consideration. T cell function was evaluated in the presence and absence of accessory cells. With concanavalin A and anti-CD3 activation, NAC enhanced mitogenesis by approximately 2- to 2.5-fold at 5-10 mM. Mitogenesis of purified T cells with anti-CD2 was not affected by NAC; in the presence of accessory cells, NAC enhanced mitogenesis by approximately 2-fold at 1-10 mM. Importantly, NAC levels above 10 mM completely inhibited activation of peripheral blood mononuclear cells by anti-CD2. IL-2 secreted by T cells was also enhanced by NAC, approximately 1.5-fold, but IL-2 secreted by cells from old donors was enhanced by 3-fold. In cultures of peripheral blood T cells, NAC (10 mM) stimulated growth by at least 4- to 6-fold after two passages. These results show that NAC, nontoxic even at 20 mM, is an effective enhancer of T cell function and a remarkable enhancer of growth. Results from other laboratories show that NAC, which increases glutathione levels, suppresses HIV replication presumably via suppression of the activation of transcriptional factor NF-kappa B.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in the plasma concentrations of lipids and lipoprotein fractions in dogs infected with Leishmania infantum

A study was made of serum concentrations of cholesterol, phospholipids, triglycerides, cholesterol bound to high-density lipoproteins (HDL), HDL1-cholesterol, HDL2-cholesterol and cholesterol bound to low-density lipoproteins (LDL) in 16 dogs naturally infected with Leishmania infantum (ZMON-1) taken from an endemic focus. Results were compared with those of a control group of ten healthy dogs. Statistically significant increases in cholesterol, triglyceride and LDL-cholesterol levels were observed. There was, however, a statistically significant decrease in HDL-cholesterol level, mainly at the expense of the HDL2-cholesterol subfraction. Cholesterol transport is therefore shown to undergo changes which may be attributed to the consumptive evolution of the disease, immunocomplex deposits in cells, hepatic disorders and interactions between the parasite and the normal cholesterol metabolism of the host.

Effects of ursodeoxycholic acid in patients with intrahepatic cholestasis of pregnancy

The efficacy and safety of ursodeoxycholic acid in the treatment of intrahepatic cholestasis of pregnancy was investigated in an open pilot study. Five patients received 1 gm/day of ursodeoxycholic acid during 20 days and another three patients received two identical periods of treatment separated by a 14-day interval free of the drug. Pruritus and serum levels of total bile salts and glutamic-pyruvic transaminase improved significantly during treatment with ursodeoxycholic acid. In the three patients who received two periods of treatment with ursodeoxycholic acid, pruritus and the laboratory alterations relapsed in the second week after the drug was discontinued, but they improved again when ursodeoxycholic acid was readministered. No adverse reactions were detected in the mothers or in their babies. All newborns were thriving normally during a follow-up period that lasted 5 mo after delivery. It is concluded that UDCA appears to be safe when administered in late pregnancy; its promising efficacy in the treatment of intrahepatic cholestasis of pregnancy should now be confirmed in controlled clinical trials.

[Symptomatic effect of epomediol in patients with cholestasis of pregnancy]

Epomediol is a terpenoid that prevents and reverses cholestasis induced by ethinylestradiol in the rat, apparently by improving liver cell membrane fluidity. Assuming that the pathogenesis of intrahepatic cholestasis of pregnancy (ICP) is related with increased estrogen levels, we studied the effects of epomediol in this disease. Patients hospitalized due to ICP received epomediol 900 mg/day (n = 7), or 1,200 mg/day (n = 4) orally, during 15 days. Biochemical parameters of liver dysfunction (serum bilirubin, bile salts, aminotransferase, alkaline phosphatases) were not modified during nor after epomediol administration. The severity of pruritus was significantly reduced in comparison to pretreatment status, with both doses of epomediol. A greater amelioration of pruritus was observed in patients treated with epomediol 1,200 mg/day than in patients who received 900 mg/day (to 20.7 +/- 6.2, as percent of pre-treatment severity score, versus 48.8 +/- 7.5 respectively; p < 0.05). After epomediol administration was stopped, pruritus relapsed in 6 patients; 3 of them had received the higher drug dose. After delivery, pruritus vanished and liver function tests returned to normal, in all patients. No adverse effects attributable to the drug were observed in the mothers or in their babies. The beneficial effect of epomediol on pruritus in patients with ICP appeared greater in this study than that observed recently in similar patients who received a placebo.

[Left ventricular mechanics in Chagas' disease and primary dilated myocardiopathies. A hemodynamic study]

The evolution of several mechanical parameters of left ventricular function was studied in 32 control subjects, 171 chronic chagasic and 60 primary dilated cardiomyopathy patients, which were submitted to an extensive invasive and non-invasive protocol. Preload and afterload (end-diastolic and end-systolic stress), contractile status (ejection fraction), the magnitude (mass/index) and adequacy of hypertrophy (mass/volume ratio) and afterload (systolic stress/volume ratio) were derived from the invasive explorations. There was an increased afterload in 25% of chronic chagasic patients without other evidence of early myocardial damage, which was accompanied by signs of inadequate hypertrophy. Both findings increased further with the progression of the disease. Systolic performance was initially preserved, but showed a progressive depression paralleling the clinical evolution. Patients with dilated cardiomyopathy showed a mechanical profile similar to chagasic patients with advanced degree of myocardial damage. The hemodynamic determination of mass index, mass/volume ratio, end-systolic and end-diastolic stress seem to be the best parameters for detection of early abnormalities in loading conditions of the heart in chronic Chagas, disease, and for indication and evaluation of the results of vasodilator therapy in both groups of patients.

S-adenosyl-L-methionine in the treatment of patients with intrahepatic cholestasis of pregnancy: a randomized, double-blind, placebo-controlled study with negative results

S-Adenosyl-L-methionine has been reported to induce beneficial effects in intrahepatic cholestasis of pregnancy. Because cholestasis of pregnancy has a high prevalence in Chile and a deleterious effect on fetal prognosis, we decided to verify the efficacy of S-adenosyl-L-methionine in this disease. Eighteen patients with pruritus that appeared during pregnancy and with elevated serum levels of bile salts (68.1 +/- 15.9 mumol/L; mean +/- S.E.M.) and ALT (226 +/- 50 KU/L) were enrolled in a prospective double-blind study comparing the effects of the drug with a placebo. S-Adenosyl-L-methionine, 900 mg, or placebo was administered in daily intravenous infusions for 20 days. Every 5 days liver function tests were done and pruritus was assessed using a preestablished score. No significant differences in pruritus or in serum levels of bile salts, ALT, bilirubin and alkaline phosphatases were seen during or after treatment between patients who received S-adenosyl-L-methionine (n = 9) or placebo (n = 9). No relevant adverse reactions were detected. Most patients had cesarean sections because of reasons unrelated to the therapeutic trial. All newborns had Apgar scores greater than 7 and normal postnatal development. Our patients had moderately severe to severe cholestasis of pregnancy as indicated by the onset of pruritus before wk 32 of pregnancy. Seven of nine multiparous patients had a past history of recurrent cholestasis of pregnancy. In this study, the administration of S-adenosyl-L-methionine during 20 days did not improve intrahepatic cholestasis of pregnancy.

[Ventricular mechanics and cardiac arrhythmias in patients with chagasic and primary dilated cardiomyopathy. Echo-electrocardiographic follow-up]

PURPOSE

To determine the prognostic significance of several parameters of left ventricular mechanics and of complex ventricular arrhythmias.

PATIENTS AND METHODS

184 chronic chagasic and 85 primary dilated cardiomyopathy patients were submitted to non-invasive and invasive studies, including Holter monitoring and "M" mode echocardiogram and followed for a maximum of 8 years.

RESULTS

Finding of a depressed left ventricle (LV) systolic function (% AC) was the most important independent prognostic factor in both groups of patients. The presence of complex ventricular arrhythmias had an additional, but very limited, independent prognostic importance, observed only in chagasic patients with depressed LV systolic function. When patients with similar degrees of left ventricular systolic dysfunction, inadequate hypertrophy or increased afterload were compared, chagasic patients had significantly worse prognosis than those with primary dilated cardiomyopathy. This is partly attributed to higher prevalence of complex ventricular arrhythmias.

CONCLUSION

The higher prevalence of complex ventricular arrhythmias in patients with chronic Chagas' disease may explain the prognostic differences between the groups.

[Effects of ursodeoxycholic acid in patients with cholestasis of pregnancy]

In an open, pilot study, the efficacy and safety of ursodeoxycholic acid (UDCA) in the treatment of intrahepatic cholestasis of pregnancy was investigated. Four patients received 1 g/day of UDCA during 20 days and another 2 patients received 2 identical periods of treatment separated by a 14-day interval free of drug. Pruritus and serum levels of total bile salts and glutamic-pyruvic transaminase improved significantly during treatment with UDCA. Although pruritus and the laboratory alterations had a relapse in the second week after UDCA was discontinued, they improved again in the 2 patients who received a second treatment with UDCA. No adverse reactions were detected in the mothers or in their babies. All newborns are thriving normally, in a follow-up that lasted 3 to 6 months after delivery. It is concluded that UDCA appears to be safe when administered in late pregnancy; its promising efficacy in the treatment of intrahepatic cholestasis of pregnancy should now be confirmed in controlled clinical trials.

Ventricular arrhythmias and left ventricular myocardial function in chronic chagasic patients

To study the relationship of complex ventricular arrhythmias to the presence and extent of myocardial damage, 556 chronic chagasic patients were submitted to an extensive protocol, including left ventricular cineangiography and Holter monitoring, and properly classified according to clinical, electrocardiographic and hemodynamic findings. Stages of the clinical-hemodynamic classification corresponded to increasing degrees of myocardial damage, age, prevalence and complexity of ventricular arrhythmias. Myocardial damage (particularly left ventricular dilatation) was the most important clinical factor linked to the presence of complex ventricular arrhythmias. A clear difference in terms of ventricular function was found only when arrhythmias were grouped into simple (Lown grades I and II) and complex (grades III and IV) forms. It is recommended that any classification for chagasic patients must be based on signs of myocardial involvement, instead of clinical or electrocardiographic findings alone. Evaluation should include accurate determination of left ventricular myocardial function, along with the search for the presence of complex ventricular arrhythmias and abnormalities of conduction.

[Chronicle of an announced death: the end of intrinsic asthma]

The word "intrinsic" asthma which is not usually quoted by French authors should be eliminated from the medical vocabulary. Similar past history, clinical symptoms, house or occupational exposure are found in all varieties of asthma. Histological features are the same in atopic asthma and late onset asthma, apparently non allergic. On immunologic point of view there are two types of IgE receptors type I on mastocytes, type II on inflammatory cells, with immunomodulation by IL4 and T lymphocytes. On the other hand, atopic status is an autosomic dominant inherited trait, with a gene locus on the chromosome 11 Q and may be transferred with bone marrow cells graft. Finally asthma appears to be a local variety of IgE hyperresponsiveness to environmental factors. These basic notions have practical consequences and legal aspects.

[Clinical and paraclinical differences between chronic Chagas' cardiomyopathy and primary dilated cardiomyopathies]

With the purpose of establishing clinical and paraclinical differences among chronic chagasic (MCh) and primary dilated cardiomyopathies (MCDP), 96 MCh and 104 MCDP patients with abnormal ECG were submitted to a study protocol which included clinical history, routine laboratory serology for Chagas' diseases, resting ECG, Chest-X-rays, and cardiac catheterisation. Patients with congestive heart failure (CHF) had common clinical and para-clinical findings. However, chagasic patients without CHF showed more prevalence of RBBB and LAH, complex ventricular arrhythmias and more left ventricular dilation while primary dilated cardiomyopathy patients with CHF had predominantly LBBB, simple ventricular arrhythmias, atrial fibrillation and less LV dilation than MCh patients. In order to establish the prognostic value of these findings and response to modern medical therapy, prospective studies on these two groups of patients are needed.

Intrahepatic cholestasis of pregnancy in twin pregnancies

To clarify whether the increase in estrogen levels occurring during twin pregnancies (TP) is associated with a greater risk of developing intrahepatic cholestasis of pregnancy (ICP), we followed up 62 consecutive patients with TP and compared them with single pregnancies delivered in our hospital during 1 year. The prevalence of ICP was significantly higher in twin than in single pregnancies (20.9% versus 4.7%, respectively; P less than 0.001). Urinary estriol excretion was also significantly higher in twin compared to single pregnancies, although no quantitative differences were detected in TP with or without ICP. In multiparous patients with a proband TP affected by ICP, the disease recurred only in further TP, emphasizing the important role that estrogens seem to play in the pathogenesis of ICP. In contrast, in multiparous patients with a proband single pregnancy affected by ICP, the disease occurred in 70.5% of their other single pregnancies, suggesting the presence of a metabolic predisposition in these cases. However, in both groups of multiparous women a notable number of single pregnancies were not affected by the disease, supporting the postulate that the pathogenesis of ICP is multifactorial and that some as yet unidentified environmental factor needs to be present in order to develop the disease and also to modulate its expressivity.

[Left ventricular mechanics in Chagas' disease and dilated cardiomyopathy: echocardiographic study]

For purposes of studying left ventricular mechanics, 184 chronic chagasic and 85 primary cardiomyopathy patients were submitted to an extensive invasive (LV cine, right and left cardiac catheterization and coronarography) and non-invasive protocol. The afterload, (mean wall stress), the contractile status (ejection fraction and circumpherential shortening) and the degree of hypertrophy (mass index) were assessed by M mode echocardiography. There was a very early increase of afterload in 8% of chagasic patients without evidences of LV myocardial involvement in the left cineventriculogram (group I-A). This increased afterload was accompanied by signs of inadequate hypertrophy in 15% of patients with early segmental myocardial damage (group IB). In contrast, ejection fraction and % circumpherential shortening were depressed only in patients with clinical evidences of congestive heart failure. Dilated primary CM patients showed similar findings, except for a more evident depression of contractility in those cases without signs of congestive heart failure (group II) and more hypertrophy than equivalent group III chagasic patients. Measurements of mean systolic wall stress and mass index are valuable parameters for identification of those patients with early increased after-load and inadequate hypertrophy which could benefit from the administration of oral vasodilators.

Enzymatic determination of serum neuron-specific enolase in small cell lung cancers. Utility of the serum neuron-specific enolase/serum nonneuronal enolase ratio

Increasing interest is shown in the determination of the serum neuron-specific enolase for the diagnosis and the follow-up studies of small cell lung cancers. We report results obtained by an enzymatic procedure that permits the simultaneous determination of the neuron and nonneuron-specific enolase and the calculation of the ratio of these two components. The utility of this ratio which characterizes elevations of the serum neuron-specific enolase from a poor or rich source of this component was tested in 38 patients with small cell lung carcinoma and in 57 subjects suffering from other bronchogenic cancers. The control group consisted of 37 blood donors and 56 patients with respiratory disease. For the diagnosis, the sensitivity and the specificity of the enzymatically determined neuron-specific enolase compared well with published results obtained by radioimmunoassay and enzymoimmunoassay. The use of the ratio clearly increases the specificity of the test, since only 5.3 percent of false positive results are found when bronchogenic tumors other than small cell carcinoma are studied. The sensitivity was 76 and 100 percent in diagnosis of limited and extensive forms, respectively. The use of this ratio in the follow-up of the patients and for the determinations in hemolyzed samples is set out.

Role of cardiac atria in the human renal response to changing plasma volume

We examined the role of cardiac atria in the renal response to sequential volume expansion and contraction, during and directly following water immersion. In immersed healthy volunteers (group 1, n = 9) atrial diameter, plasma levels of atrial natriuretic peptide (ANP), and natriuresis increased, whereas renal vascular resistance (RVR) and filtration fraction declined. Each parameter changed in an opposite direction postimmersion. An analysis of transglomerular dextran transport suggests that transglomerular hydraulic pressure difference (delta P) changed in parallel with filtration fraction. Baseline atrial diameter, plasma ANP, RVR, and filtration fraction were significantly elevated in nine recipients of denervated cardiac allografts (group 2). Atrial diameter and plasma ANP changed in parallel with group 1 during and after immersion. However, corresponding reciprocal changes in RVR were smaller and filtration fraction remained constant throughout. From transglomerular dextran transport, we compute that delta P increased progressively during and after immersion, suggesting predominant efferent arteriolar tone. The postimmersed state was associated also with enhanced sodium retention despite sixfold higher plasma ANP than in group 1. These findings are consistent with an effect of cardiac denervation to leave unopposed efferent sympathetic nervous traffic to the kidney. They suggest that the latter is an important modulator of the renal response to changing plasma volume in humans.