Characterization of a candidate Trypanosoma brucei U1 small nuclear RNA gene

We have previously shown that the poly(A) polymerase (PAP) gene of Trypanosoma brucei is interrupted by an intervening sequence. It was postulated that removing this intron by cis-splicing requires a yet unidentified U1 small nuclear RNA (snRNA), which in other organisms engages in base-pair interactions across the 5' splice site during early spliceosome assembly. Here we present a characterization of a 75 nucleotide long candidate T. brucei U1 snRNA. Immunoprecipitation studies indicate that a trimethylguanosine cap structure is present at the 5' end and that the RNA is bound to core proteins common to spliceosomal ribonucleoprotein particles. The U1 snRNA has the potential for extensive intermolecular base pairing with the PAP 5' splice site. We used block replacement mutagenesis to identify sequences necessary for in vivo expression of U1 snRNA. We found that at least two cis-acting elements, tRNA-like A and B boxes, located in the 5'-flanking region are necessary for U1 snRNA synthesis; no internal sequences close to the transcription start site are essential, suggesting a promoter architecture distinct from other trypanosome U-snRNA genes.

Daily production of human tumor necrosis factor in lipopolysaccharide (LPS)-stimulated ex vivo blood culture assays

Tumor necrosis factor (TNF) is a pleiotropic cytokine with immunological and neuroendocrine activities. A useful tool for studying TNF is the measurement of its in vitro and/or ex vivo over-expression, induced by a variety of stimuli on isolated peripheral mononuclear cells or whole blood, respectively. The capacity to over-express TNF, in ex vivo LPS-stimulated whole blood from 18 normal individuals, showed inter-individual variations ranging from high (3 ng/ml) to low (0.7 ng/ml) producers. Although at a lower level, a similar situation was observed in the spontaneous production of the cytokine. In order to detect cyclic effects in these variations, blood samples were taken at 08:00, 12:00, 16:00 and 20:00 hours, from nine healthy volunteers, and cultured in the ex vivo system. TNF and cortisol were measured by immunometric assays. Both, LPS-stimulated whole blood and plasma showed important, individual variations in TNF levels. Although cortisol levels presented a normal circadian cycle, these individual patterns in TNF production were basically conserved during the day (p > 0.05), and no correlation was observed between the levels of the hormone and those of the cytokine. When total TNF levels were determined at 20:00 hours, a moderate, temporary variation pattern of the cytokine production was found. These results suggest that cortisol does not play a predominant role in determining the ex vivo capacity of blood to produce TNF. Presumably, the variable capacity to produce the cytokine may have a strong genetic component.

Tc45, a dimorphic Trypanosoma cruzi immunogen with variable chromosomal localization, is calreticulin

We demonstrate that Tc45, a polypeptide described as an immunogenetically restricted Trypanosoma cruzi antigen in mice, is calreticulin, a dimorphic molecule encoded by genes with variable chromosomal distribution. Previously we showed that IgG from A.SW (H2s) mice immunized with T. cruzi trypomastigotes or epimastigotes and sera from infected humans recognize Tc45, a 45 kD parasite polypeptide. Herein we describe the cloning, sequencing, and expression of the Tc45 gene. A 98% homology in the deduced amino acid sequence was found with a T. cruzi calreticulin-like molecule and 41% with Leishmania donovani and human calreticulin. In the T. cruzi CL Brener clone and in the Tulahuén strain, the gene is located in two and four chromosomes, respectively. Calreticulin was detected in several T. cruzi clones, in the Tulahuén strain, and in T. rangeli, displaying alternative 43 and 46 kD forms.

Development of an immunoenzymatic assay for the detection of human antibodies against Trypanosoma cruzi calreticulin, an immunodominant antigen

We have developed an indirect immunoenzymatic assay (ELISA) for the detection of human antibodies against calreticulin (formerly known as Tc45), a dimorphic Trypanosoma cruzi antigen, described in our laboratory. PVC microtitration plates were sensitized with the monoclonal anti-calreticulin antibody (MoAb) and reacted with calreticulin present in a partially purified preparation. The presence of anti-T. cruzi calreticulin IgG in sera from infected individuals was tested. The data generated with this assay were validated by correlation, in a regression analysis, with those obtained by an indirect immunoradiometric assay (IRMA). From the 12 seropositive sera (as defined by a commercial test), eight came out positive and four negative in both assays. The 12 human sera were also analyzed in direct immunometric assays (ELISA and IRMA), where the solid phase was sensitized with a whole parasite extract. The direct ELISA and IRMA correlated positively (P<0.01). Further validation of this ELISA was achieved with an indirect immunofluorescense assay. The high degree of significance obtained when the indirect IRMA and ELISA systems were compared, indicated that the relatively small sample number used (12) was statistically satisfactory for the purposes of this investigation. Thus, the IRMA can be replaced by the ELISA, with advantages mainly derived from the cumbersome manipulation of radioactive wastes. The MoAb used as an antigen capture agent in the ELISA proposed here, recognizes a homologous protein in Trypanosoma rangeli, suggesting that individuals infected with this parasite might have crossreactive antibodies. However, the system retains its diagnostic interest, given the facts that the MoAb does not recognize a homologous protein in Leishmania mexicana, Leishmania donovani, or Crithidia fasciculata.

Evaluation of poly(2-hydroxyethyl methacrylate) gels as drug delivery systems at different pH values

Studies of dynamic and equilibrium swelling, structural characterisation and solute transport in swollen poly(2-hydroxyethyl methacrylate) gels (pHEMA) cross-linked with tripropyleneglycol diacrylate (TPGDA) were done for a wide range of TPGDA concentrations. The influence of the pH on these pHEMA properties was evaluated. In swelling studies it was found that in changing the pH from 6.5 to 12.0, a large increase in swelling occurred, from approximately 48 to 55%, for the lowest concentration of TPGDA (1 mol%), and from 40 to 80% for the highest concentration (10 mol%). Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC) measurements were made after the equilibrium swelling of the gels at different pH values, to explain these results. The advantage of using these gels as controlled drug delivery systems is illustrated using salicylic acid (SA) as a model drug. The loading and the release of the SA were made at different pH values and the results obtained showed that it is possible to modulate the hydrogel performance by controlling an external factor, the pH at which the drug loading and release were performed.

[The metabolic-chronotropic relation in patients with heart failure--a correlation with functional capacity]

Previous studies on chronotropic incompetence (CI) in patients with congestive heart failure (CHF) have defined it as the inability to achieve > 80% of age predicted maximum heart rate (HR) (adequacy of HR response to submaximal exercise levels not being considered). The metabolic chronotropic relation (MCR) concept proposed by Wilkoff allows the assessment of the entire chronotropic function. The value of such an approach for the evaluation of CI in patients with CHF, and its relation to exercise capacity, is unclear at present.

METHODS

We imposed maximal symptom-limited treadmill exercise testing while measuring breath-by-breath oxygen consumption, using CAEP protocol, in 25 patients (19 men), 49 +/- 10 years, all in sinus rhythm, with CHF secondary to dilated cardiomyopathy (17) or ischemic heart disease (8), NYHA class II-III. Anaerobic threshold (AT) was attained by all. No exercise was terminated due to arrhythmia or ischemia. MCR was calculated as the slope of the relation between the percentages of HR and metabolic reserves achieved at the end of each exercise stage. Using 2.0 standard deviations below the mean level of MCR in healthy controls, we defined an MCR value < 0.84 as abnormal. The parameters analysed were: age, drug therapy, fractional shortening (FS-%), resting HR (RHR-bpm), exercise duration (DUR-min), peak HR (HRp), peak oxygen consumption (VO2p-ml/kg/min), percentages of predicted maximal HR (% PMHR) and VO2 (% PMVO2), peak ventilatory equivalent for CO2 (VE/VCO2-L/min), time to AT (T-AT), and VO2 at AT (VO2-AT).

RESULTS

MCR was normal (1.01 +/- 0.18-0.86 to 1.19) in 10 patients--Group I, and abnormal (0.66 +/- 0.13-0.42 to 0.81) in 15 (60%) patients--Group II. A similar proportion of patients in both groups were taking ACE inhibitors, digoxin and amiodarone. [table: see text] CI defined as an inability to achieve a % PMHR > 80% occurred only in 6 (24%) patients, all in Group 2 (p = 0.022 versus abnormal MCR).

CONCLUSIONS

In CHF patients, CI assessed as an abnormal MCR is frequent, and relates to an impaired exercise capacity.

[The nonpharmacological treatment of atrial fibrillation]

The authors describe the main forms of nonpharmacological treatment of atrial fibrillation considering catheter ablation and surgical therapy. A new methodology to modify atrioventricular conduction is discussed as well its long-term results. All studies are non-randomised with selected patients, which makes the development of a therapeutical algorithm difficult. However, the results have shown that it is possible to recover sinus rhythm through surgery or catheter ablation and to control the ventricular rate either by His ablation or modification of atrioventricular conduction.

[The influence of therapy (sympathomimetic amines versus vasodilators) in the indexes of ejection fraction derived from an analysis of Doppler aortic flow]

PURPOSE

To assess the influence of inotropic IV therapy--dobutamine and/or dopamine--versus vasodilator therapy--nitroprusside, captopril or hydralazine--in aortic flow ejection phase indexes obtained by pulsed Doppler echocardiography.

METHODS

In 17 patients admitted to the ICU (11 males, 62 +/- 14 years, 9 with ischemic cardiomyopathy and 8 with dilated cardiomyopathy, all in sinus rhythm), with congestive heart failure, and submitted to tailored therapy, 53 serial pulsed Doppler and hemodynamic evaluations were made as the therapy changed the hemodynamic and clinical status. Considering serial consecutive evaluations, a hemodynamic improvement was obtained only with inotropics in 13 (group A), and with vasodilators in only 15 (group B). The following ejection phase indexes were calculated from Doppler registers: average acceleration (AvAc) and ejection force (EFor), calculated according to the formula: Efor = 1.06 x Aortic Orifice Area x AvAc x Acceleration Velocity Time Integral.

RESULTS

Arterial blood pressure increased in gr A (76.2 +/- 14.1 to 81.4 +/- 14.8 mm Hg, p < 0.05) and decreased in gr B (85.1 +/- 12.6 to 76.2 +/- 9.7 mm Hg (p < 0.05). In both groups there was a significant (p < 0.05) increase in cardiac output (CO)-from 3.9 +/- 1.1 to 4.9 +/- 1.4 L/min in group A, and from 3.9 +/- 1.2 to 4.4 +/- 1.2 L/min in group B. CO increased 18.7% in group A and 13.8% in group B (NS). There was a decrease in pulmonary capillary wedge pressure (PCWP) from 19.5 +/- 6.0 to 15.1 +/- 5.8 mm Hg in group A (p < 0.05), and from (16.9 +/- 5.7 to 12.1 +/- 4.6 mm Hg in group B (p < 0.05). PCWP decreased 19.7% in group A and 27.8% in group B (NS). Systemic vascular resistance (SVR) changed from 18.2 +/- 7.0 to 16.2 +/- 7.1 Wood U in group A (p < 0.05), and from 22.3 +/- 9.3 to 17.7 +/- 5.7 Wood U in group B (p < 0.05). In group A, AvAc increased-from 1347 +/- 611 cm.s-2 (p < 0.05), as did Efor-from 15.4 +/- 10.7 to 20.2 +/- 11.0 g.cm,s-2 (p < 0.05), whereas in group B there was no significant change in either AvAc-from 1337 +/- 284 to 1277 +/- 256 cm.s-2, or Efor-from 22.7 +/- 17.0 to 23.8 +/- 15.0 g.cm.s-2.

CONCLUSIONS

Vasodilator therapy, although inducing hemodynamic changes similar to inotropics, does not alter the ejection phase indexes. Therefore, AvAc and Efor, in spite of being calculated from the aortic flow, are independent of the changes in PCWP and SVR and seem to reflect changes in inotropism in the clinical setting.

Use of combination of low-dose cyclosporine and RS-61443 in a rat hindlimb model of composite tissue allotransplantation

Despite technical feasibility, composite tissue allotransplantation has not been applied clinically because of immunosuppressive toxicity associated with these highly antigenic allografts. Combination immunosuppression therapy can help overcome this obstacle by allowing lower doses of individual drugs and minimizing toxicity. RS-61443 (mycophenolate mofetil), an effective immunosuppressant that inhibits lymphocyte proliferation, was tested at subtherapeutic doses in combination with cyclosporine (CsA) in a rat hindlimb allotransplantation model with a major antigenic mismatch at the MHC. Five groups were studied: untreated autograft controls (n=4), untreated allograft controls (n=6), allografts receiving low-dose CsA 1.5 mg/kg/day (n=11), allografts receiving low-dose RS-61443 15 mg/kg/day (n=17), and allografts receiving combination low-dose CsA 1.5 mg/kg/day + RS-61443 15 mg/kg/day (n=18). The autograft controls survived indefinitely, while untreated allograft control animals developed severe rejection within 12 days. Subtherapeutic CsA and RS-61443 monotherapy groups developed acute rejection in 64% and 100% of rats, respectively. In contrast, only 11% of rats receiving combination therapy with CsA + RS-61443 at these same subtherapeutic doses developed acute rejection (P < or = 0.0013). Bone marrow toxicity, manifested primarily by anemia and measured objectively by hematocrits, was reduced significantly (P=0.04) in animals receiving low-dose RS-61443 therapy when compared with high-dose controls. These results confirm that subtherapeutic RS-61443 + CsA combination therapy is efficacious in preventing rejection while minimizing toxicity.

Hsp47 and the translation-translocation machinery cooperate in the production of alpha 1(I) chains of type I procollagen

Hsp47, an endoplasmic reticulum resident protein, has gelatin-binding and procollagen-binding properties and has been hypothesized to function as a molecular chaperone in regulating procollagen folding and/or assembly. In this report, we further investigate the interaction of Hsp47 with polysome-associated alpha 1(I) procollagen chains following antisense treatment of 3T6 cells. For these studies, we employed phosphorothioate oligodeoxynucleotides directed to the first five codons of Hsp47 that straddle the predicted translation initiation site of mouse Hsp47. Cells depleted of Hsp47 in this manner were observed to produce diminished amounts of fully elongated nascent alpha 1(I) procollagen while accumulating shorter procollagen peptides associated with peptidyl-tRNA. Pulse-labeling of cells with [35S]methionine followed by treatment with puromycin and immunoprecipitation with anti-Hsp47 and anti-procollagen antibodies revealed that Hsp47 is associated with alpha 1(I) procollagen at a very early point during translocation of the nascent procollagen chains. Although Hsp47 appears to possess properties similar to grp78/BiP, Hsp47 binding early during translocation favors a more specialized specific function relative to chain selection or completion of stable folding in type I procollagen.

[The assessment of the histomorphological characteristics of the arteria gastroepiploica dextra and its potential as an artery for myocardial revascularization]

OBJECTIVE

Comparative analysis of the histomorphological characteristics of left (LIMA) and right (RIMA) internal mammary arteries, right gastroepiploic (RGEA) and anterior descending artery (ADA) with evaluation of the respective prevalence of atherosclerotic changes.

SETTINGS

Laboratory of Anatomo-Pathology of a Central Hospital with necropsy material obtained from consecutive individuals, deceased of a non-cardiac cause and older than 60 years.

MATERIAL AND METHODS

In 31 cadaver fragments of the RIMA, LIMA, GEA and ADA, were obtain, subsequently fixed and stained in order to become evident the structure of the medial layer, and the presence of possible atherosclerotic changes (intimal Hyperplasia, cholesterol clefts, foam-cells, inflammatory cells infiltrate, rupture of the internal elastic lamina, medial fibroses and calcifications).

RESULTS

1--The RGEA has the structure of a muscular artery as the ADA, opposed to the LIMA and RIMA that are elastic arteries. 2--The atherosclerotic changes were predominantly found in the ADA with no significative differences in there prevalence in the RIMA, LIMA or RGEA.

CONCLUSIONS

The RGEA despite having histological characteristics diverse than the LIMA and RIMA, has a similar prevalence of atherosclerotic changes and intimal hyperplasia; those allow us to predict a behaviour and a long-term patency comparable, when used as bypass graft for myocardial revascularization.

[The sensitivity and specificity of the clinical, serological and tomographic diagnosis of Toxoplasma gondii encephalitis in the acquired immunodeficiency syndrome (AIDS)]

Toxoplasmic encephalitis (TE) is among the most common neurologic affections and it is the most prevalent cause of intracerebral mass lesions in AIDS patients. All patients with AIDS hospitalized at the Hospital de Clínicas de Porto Alegre between May/85 and December/91 (516 cases) had their files revised to determinate TE prevalence, serology, sensitivity and specificity of the computed tomography (CT) brain scan, clinical findings and serology to make its diagnosis. The prevalence on CT was 13% (presumptive diagnosis). Blood serology and cerebrospinal (CSF) serology to toxoplasma were positive respectively in 65% and 49%. Autopsies of 125 patients were also revised with a prevalence of 22% (definite diagnosis). CT scan had 65% of sensitivity and 82% of specificity. Sensitivity and specificity of serology on blood was respectively 95% and 30%, while the cerebrospinal fluid (CSF) serology had 77% of sensitivity and 56% of specificity. The following clinical findings were considered: fever (sensitivity = 92%; specificity = 56%), neurological focal signs (sensitivity = 59%; specificity = 82%) and headache (sensitivity = 41%; specificity = 69%). We conclude that, based on the high serology sensitivity and high CT scan specificity, they constitute an useful approach to make TE diagnosis.

[Contribution of Holter monitoring in the diagnosis of a case of Prinzmetal's angina]

Prinzmetal angina is a peculiar kind of angina pectoris, in which Holter monitoring has been particularly useful for diagnosis. In this paper it is reported a 56 years old male patient with coronary artery spasm induced during coronary arteriography in which the Holter electrocardiography was of most importance for decision making.

Large Area Position Sensitive Detector Based on Amorphous Silicon Technology

We have developed a rectangular dual-axis large area Position Sensitive Detector (PSD), with 5 cm × 5 cm detection area, based on PIN hydrogenated amorphous silicon (a-Si:H) technology, produced by Plasma Enhanced Chemical Vapor Deposition (PECVD). The metal contacts are located in the four edges of the detected area, two of them located on the back side of the ITO/PIN/A1 structure and the others two located in the front side. The key factors of the detectors resolution and linearity are the thickness uniformity of the different layers, the geometry and the contacts location. Besides that, edge effects on the sensor's corner disturb the linearity of the detector. In this paper we present results concerning the linearity of the detector as well as its optoelectronic characteristics and the role of the i-layer thickness on the final sensor performances.

Coronariographic significance of heart rate variation related to ischemic episodes in patients undergoing peripheral vascular surgery

OBJECTIVES

To evaluate the characteristics of myocardial ischemia during daily life and their coronariographic significance in a group of patients with proven coronary artery disease undergoing peripheral vascular surgery.

SETTING

Department of Cardiology--Central Hospital--Lisbon.

METHODS

In 14 patients undergoing peripheral vascular surgery and in whom coronariography revealed coronary significative lesions, Holter monitoring was performed during a 24-hour period. Two groups of ischemic episodes were considered: Group A constituted by 44 episodes detected in patients with left main or three vessel disease and group B by 12 episodes detected in patients with one ot two vessel disease. In each group the ischemic parameters were studied.

RESULT

The incidence of myocardial ischemia was 64%. Statistically significant differences were observed between group A and B concerning the mean heart rate variation from two minutes before the onset of ST-segment depression to its onset (2.39 bpm vs 8.75 bpm; p < 0.05), from the onset of ST-segment depression to its maximal depression (4.43 bpm vs 16.67 bpm; p < 0.001) and from two minutes before St-segment depression to its maximal depression (6.82 bpm vs 25.4 bpm; p < 0.00001). No differences were found in duration and maximal ST-segment depression.

CONCLUSION

Particular characteristics of heart rate variation related to the ischemic episodes seem to have a relation with the severity of coronary artery disease in patients undergoing peripheral vascular surgery.

[The neuropathological findings in the acquired immunodeficiency syndrome (AIDS): a review of 138 cases]

This is an autopsy study performed in a retrospective fashion to determine the incidence of diseases that could affect the central nervous system in AIDS. For this purpose, 138 autopsies of patients with AIDS performed at the "Hospital de Clínicas de Porto Alegre", Brazil, between January/85 and December/90 were studied. All the brains were evaluated macroscopically and microscopically mainly through hematoxylin-eosin staining and if necessary special techniques like PAS, Grocott, Giemsa and Ziehl-Nielsen were done. Results have revealed 29 (21%) cases with cerebral toxoplasmosis; cryptococcosis in 17 (12%); tuberculosis in two (1%) and one case (0.7%) of candidiasis. Besides these inflammatory lesions, 15 (10%) presented vascular lesion; 8 (6%) had gliosis and 7 (5%) cases had suggestive findings of HIV encephalopathy. We can conclude that the CNS is a important target affected by AIDS and that cerebral toxoplasmosis is the principal disease in the CNS in AIDS patients.

[Hemodynamic assessment after heart transplantation]

OBJECTIVE

Comparative analysis of the results of the hemodynamic evaluations performed at the preoperative period, during the first week and at the end of the first and second years, after orthotopic heart transplantation.

DESIGN

Retrospective study of hemodynamic evaluation of patients submitted to orthotopic cardiac transplantation from April 1987 to April 1990.

SETTING

Transplanted patients admitted at the cardiology and cardio-toracic surgery departments of the Hospital Santa Marta.

PATIENTS

15 patients (eleven males and four females) aged 21 to 55 years (mean = 33.3 +/- 10.5), with the preoperative diagnosis: dilated cardiomyopathy in 11, ischemic heart disease in three and hypertrophic cardiomyopathy in one patient. All the patients were on triple immunosuppressive therapy (cyclosporine A, azatioprine and prednisolone) at the time of the first week evaluation. Three of the eight patients evaluated at the end of the first year were with double immunosuppressive regimen (without steroids), seven at NYHA functional class I and one patient at class II. The three patients evaluated at the end of the second year were on triple immunosuppressive regimen and in class I.

INTERVENTIONS

We considered, preoperatively (PrOp), at the first week (1W), and at the end of the first (1Y) and second (2Y) years: mean right atrial pressure (RA), systolic pulmonary arterial pressure (PAs), mean pulmonary arterial pressure (PAm), pulmonary capillary wedge pressure (PCW), mean systemic arterial pressure (SAm), cardiac index (CI), pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR). At 1Y and 2y there were also considered the left ventricular end-diastolic pressure (LVEDP) and the ejection fraction (Ej).

RESULTS

(table; see text) The results found at 2Y were similar to those showed at 1Y. At 1Y and 2Y LVEDP and Ej were normal.

CONCLUSIONS

A high prevalence of mild to moderate hemodynamic disturbances characterizes the early post-operative period in cardiac transplantation. Abnormal pressures on right atrium, pulmonary artery, pulmonary capillary wedge pressure, are found on a significant number of patients, and pulmonary and systemic vascular resistances are also elevated. However at the end of the first year there is a significant improvement compared with the first week. Normality is the hallmark of hemodynamic evaluation performed in transplant recipients at the end of the first and second years.

[Exercise test parameters after acute myocardial infarction. Relationship with coronary angiography]

OBJECTIVE

To analyze the relation between characteristics of symptom-limited treadmill exercise stress test, after acute myocardial infarction (MI) and coronariographic results (number of diseased vessels). Both tests were performed before hospital discharge.

DESIGN

Retrospective study with comparative analysis between variable defined groups.

POPULATION AND SETTING

From 232 patients interned in the department of Cardiology of Hospital de Santa Marta with a first acute MI, a population of 112 patients submitted to exercise stress test and coronary angiography before discharge were selected (aged 29 to 69 years).

METHODS

Symptom-limited treadmill exercise stress tests were performed according to Bruce protocol, with no heart-rate limitation. The following parameters were analyzed: Stress test duration (DUR); Double product variation (varDP); Metabolic equivalent units (METS); Maximal heart rate (FCmax); Percentage of the maximal reached heart rate (% FCmax); Incidence of ST segment depression (InfST); Maximal ST segment depression (Max-InfST); Onset minute of ST segment depression (MinInfST); Heart rate at the onset of ST segment depression (FCInfST); Double product at the onset of ST segment depression (DPInfST); Recovery minute of ST segment depression (MinRInfST); Onset minute of angina (MinAng); Heart rate at the onset of angina (FCAng); Double product at the onset of angina (DPAng).

RESULTS

Statistical significant differences were obtained between coronariographic groups concerning the following parameters: DUR: 1-vessel/3-vessel P = 0.02; VarDP: 1-vessel/3-vessel p = 0.008, 2-vessel/3-vessel p = 0.004; METS: 1-vessel/3-vessel p = 0.01. No differences were seen between anterior and inferior myocardial infarctions regarding all the stress test parameters. However in patients with anterior MI significant differences were obtained concerning the following variables: VarDP: 1-vessel/2-vessel p = 0.02; InfraST: 1-vessel/2-vessel p = 0.006, 1-vessel/3-vessel p = 0.03; MaxInfST: 1-vessel/2-vessel p = 0.01, 1-vessel/3-vessel p = 0.0006; Angina: 1-vessel/2-vessel p = 0.0005, 1-vessel/3-vessel p = .001. In inferior myocardial infarctions only the stress duration differed between 1-vessel and 3-vessel groups (p = 0.003).

CONCLUSIONS

Symptom-limited treadmill exercise stress tests, safely performed in our institution, were an important method for post MI evaluation and allowed the diagnosis of a great number of patients with residual ischemia. Statistical significant differences were found in ergometric parameters, between coronariographic groups (defined by the number of diseased vessels), emphasising the importance of stress tolerance analysis.

[Biopsy of the right ventricle endomyocardium. Experience at the Santa Marta Hospital]

OBJECTIVE

To review the experience of Santa Marta Hospital in the right ventricle endomyocardial biopsy technique.

DESIGN

Retrospective analysis of the results, diagnostic value and complications of the myocardial biopsies performed between April/87 and March/90.

PATIENTS AND INTERVENTIONS

255 biopsies were performed; 221 on 13 patients submitted to orthotopic heart transplantation (nine male and four female, aged between 21 and 55 years old), and the remaining on 34 patients (22 male and 12 female aged between 15 and 64 years old), mainly on cardiomyopathies.

RESULTS

In 221 biopsies performed in heart transplant recipients, we found: 109 with no rejection, 21 with moderate rejection, 57 with mild rejection and only one case showed severe rejection. In this group six biopsies were considered inconclusive. In the group of patients not submitted to heart transplantation the histological findings were inespecific in the great majority of the cases. In the 255 procedures four complications were detected (1.56%), with no mortality; two hemopericardium with tamponade (0.78%), one pneumothorax and one atrial fibrillation.

CONCLUSIONS

Endomyocardial biopsy essential for histological diagnosis of acute rejection following heart transplantation has revealed to be a save procedure with a small number of complications.

[Influence of recipient auricular contraction on the left ventricle filling pattern of the transplanted heart studied with pulsed Doppler echocardiography]

OBJECTIVES

to evaluate the influence of recipient atrial contraction (RAC) timing on left ventricular filling pattern (LVFP), assessed by Pulsed Doppler, in orthotopic transplant recipients (OTR).

STUDY DESIGN

prospective study of OTR.

SETTING

patients (pts) submitted to orthotopic heart transplantation at Hospital de Santa Marta, from April/87 to March/89, in routine evaluation.

PARTICIPANTS

nine pts, aged 21 to 55 years (mean = 32 +/- 11), 0.5 to 20 (mean = 7.4 +/- 6.9) months post-operatively.

METHODS

in each pt 40 to 60 (mean 52) consecutive cardiac cycles were analysed; five groups (Gr.) were considered, according to RAC (P wave) position in the cardiac cycle: Gr. I--Early systole, GR. II--late systole, Gr. III--early diastole, Gr. IV--late diastole and Gr. V--absent. The following parameters were studied: peak early diastolic mitral flow velocity (Evel), peak late diastolic mitral flow velocity (Avel), ratio Evel/Avel, (E/A) and pressure half time (PHT).

RESULTS

1) Evel and E/A were significantly higher, Avel lower, and PHT shorter, in Gr II and III; 2) Avel was higher and E/A smaller in Gr. IV; 3) no statistically significant differences were found betwenn Gr. I and V, for any of the parameters analised.

CONCLUSIONS

the timing of RAC significantly influences LVFP and it must be considered on Echo-Doppler analysis of diastolic function in OTR.

[Flow in the entry chamber of the left ventricle. Changes with age]

OBJECTIVES

To evaluate the influence of aging in the parameters of the left ventricle diastolic function, using 2D-Doppler echocardiography.

STUDY DESIGN

Prospective study of normals subjects.

MATERIAL AND METHODS

They were studied 38 normals subjects aged between 23-70 years divided in two groups: group A--20 subjects aged less than 45 years (34.5 +/- 6) and group B--18 subjects aged greater than 45 years (55.7 +/- 8.4); we registered the left ventricle inflow flows by 2D-pulsed Doppler Echocardiography and analyzed the following indexes: E and A Velocities, E/A ratio, relations of areas under the curves of flow, E Area/Total Area (EAr/TAr), A Area/Total Area (AAr/TAr), 33% Area/Total Area (33Ar/TAr), 50% Area/Total Area (50Ar/TAr) and A Area/E Area (AAr/EAr).

RESULTS

E Vel and E/A ratio are significantly higher in the group A (p less than 0.001), both decreasing with aging, respectively r = -0.71 and r = 0.63; on the other way, the relative contribution of atrial systole to the left ventricle diastolic filling is significantly higher in the group B(ArA/ArT p less than 0.001; AAr/EAr p less than 0.001), increasing significantly with aging, r = 0.64 and r = 0.69, respectively.

CONCLUSIONS

There is an increasing of atrial contribution to the left ventricular diastolic filling in the elderly, so in comparative studies it must be used control groups with the same age.

[Flow in the entry chamber of the right ventricle: diastolic function indexes in a normal population]

OBJECTIVES

To define normal values of indexes of diastolic function of right ventricle by bidimensional pulsed doppler echocardiography.

STUDY DESIGN

Prospective study of normal individuals.

MATERIALS AND METHODS

Thirty normal subjects by physical examination, electrocardiographic, radiological and echocardiographic criteria, aged between 22-48 (mean 31.2 +/- 6.7) were evaluated. We determined 16 different indexes and correlated them with heart rate, age and body surface; 27% of cases owing to the poor quality of records, were excluded.

RESULTS

Eight indexes were heart rate dependent and for their use is necessary the respective correction; none of them correlated with age or body surface. Areas determined under the curves of flow are very time consuming and require great accuracy determination. So, we had correlated areas with other different indexes in order to obtain other parameters to give us the same information on a easier and quickly way. E/A relation correlated with all areas relations.

CONCLUSIONS

The indexes determined can be considered as normal standard in order to evaluate, by a non-invasive way, right ventricle diastolic function. Nevertheless, the great proportion of records of poor quality is a limitation of the method.

The efficacy of the D2 and 5-HT2 antagonist risperidone (R 64,766) in the treatment of chronic psychosis. An open dose-finding study

After a wash-out period of 1 week, 20 patients suffering from schizophrenia were treated for 4 weeks in an open dose-finding study with a new serotonin-dopamine antagonist risperidone. All patients completed the trial. The mean daily dose of risperidone was 4.6 mg (range 2-10 mg) at completion. Risperiodone had a rapid onset of action: a highly significant decrease of the total BPRS score (Brief Psychiatric Rating Scale) was already noticed at the end of the second week. This decrease was found in all BPRS factors after 4 weeks. In spite of the withdrawal of antiparkinson medication at selection, a clear decrease of EPS (extrapyramidal symptoms), assessed on the Simpson and Angus Scale, was observed. The Global Therapeutic Impression agreed to the BPRS scores, showing a highly significant improvement after 2 weeks of treatment. Risperidone was very well tolerated, only mild side effects were reported. Vital signs, electrocardiographic parameters and laboratory values remained normal during the trial. This study indicates that risperidone can be an effective and well-tolerated alternative in the treatment of chronic schizophrenia, combining an antipsychotic activity, a beneficial effect on anergia and anxiety depression and a low EPS-inducing profile.