Showing papers by "University of São Paulo published in 1992"

Chronic inhibition of nitric oxide synthesis. A new model of arterial hypertension.

Abstract: Recent studies have indicated that acute inhibition of nitric oxide biosynthesis in the rat promotes arterial hypertension and renal vasoconstriction. We evaluated the renal and systemic effects of 4-6 weeks of nitric oxide blockade in Munich-Wistar rats receiving the nitric oxide inhibitor nitro-L-arginine orally. Age-matched untreated rats were used as controls. In an additional seven rats, nitric oxide blockade was carried out in conjunction with oral administration of the novel angiotensin II antagonist losartan potassium. Tail-cuff pressure rose progressively in nitro-L-arginine-treated rats, reaching 164 +/- 6 mm Hg at 4-6 weeks, compared with 108 +/- 3 mm Hg in controls. In rats concomitantly receiving losartan, tail-cuff pressure reached 125 +/- 6 mm Hg, still elevated compared with rats receiving losartan alone (98 +/- 3 mm Hg). Nitro-L-arginine-treated rats presented marked renal vasoconstriction and hypoperfusion, as well as a 30% fall in glomerular filtration rate and a 39% increase in filtration fraction. Treatment with Losartan normalized glomerular filtration rate, but not filtration fraction or renal vascular resistance. Plasma renin activity was elevated after nitro-L-arginine treatment. Renal histological examination revealed widespread arteriolar narrowing, focal arteriolar obliteration, and segmental fibrinoid necrosis in the glomeruli. In a separate group of rats, nitro-L-arginine administered for 1 week induced hypertension that was partially reversed by acute L-arginine, but not D-arginine or L-glycine, infusions. We conclude that chronic nitric oxide blockade may constitute a new model of severe arterial hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

The spectral input systems of hymenopteran insects and their receptor-based colour vision.

Abstract: Spectral sensitivity functions S(λ) of single photoreceptor cells in 43 different hymenopteran species were measured intracellularly with the fast spectral scan method. The distribution of maximal sensitivity values (λmax) shows 3 major peaks at 340 nm, 430 nm and 535 nm and a small peak at 600 nm. Predictions about the colour vision systems of the different hymenopteran species are derived from the spectral sensitivities by application of a receptor model of colour vision and a model of two colour opponent channels. Most of the species have a trichromatic colour vision system. Although the S(λ) functions are quite similar, the predicted colour discriminability curves differ in their relative height of best discriminability in the UV-blue or bluegreen area of the spectrum, indicating that relatively small differences in the S(λ) functions may have considerable effects on colour discriminability. Four of the hymenopteran insects tested contain an additional R-receptor with maximal sensitivity around 600 nm. The R-receptor of the solitary bee Callonychium petuniae is based on a pigment (P596) with a long λmax, whereas in the sawfly Tenthredo campestris the G-receptor appears to act as filter to a pigment (P570), shifting its λmax value to a longer wavelength and narrowing its bandwidth. Evolutionary and life history constraints (e.g. phylogenetic relatedness, social or solitary life, general or specialized feeding behaviour) appear to have no effect on the S(λ) functions. The only effect is found in UV receptors, for which λmax values at longer wavelengths are found in bees flying predominantly within the forest.

Multicenter Study of the Prevalence of Diabetes Mellitus and Impaired Glucose Tolerance in the Urban Brazilian Population Aged 30–69 yr

Abstract: OBJECTIVE To assess the prevalence of diabetes and IGT in the urban adult Brazilian population. RESEARCH DESIGN AND METHODS We used a two-stage, multicenter, cross-sectional survey in a random sample of 21,847 individuals aged 30–69 yr from nine large cities. Subjects were first screened by FCG. All positive screenees (FCG ≥ 5.6 mM/L) and every sixth consecutive negative screenee were administered a 75 g OGTT and classified as diabetic, IGT, or normal (nondiabetic) according to WHO recommendations. OGTT findings from the negative screenees were extrapolated to all negative screenees after adjustments for potential biases. RESULTS The overall rates were 7.6 and 7.8% for diabetes and IGT, respectively. Men (7.5%) and women (7.6%) had similar rates of diabetes. Similar rates resulted with whites (7.8%) and nonwhites (7.3%). Diabetes prevalence increased from 2.7% in the 30–39-yr age-group to 17.4% in the 60–69-yr age-group. Diabetes was more prevalent among less educated people, but this difference disappeared after adjusting for age. Family history of diabetes was associated with a twofold increase in diabetes prevalence (12.5 vs. 5.8%); the same increase occurred with obesity (11.6 vs. 5.2%). Undiagnosed diabetes accounted for 46% of the total prevalence. Among previously diagnosed cases, 22.3% were not under treatment, 7.9% were on insulin, 40.7% were on oral agents, and 29.1% were on dietary treatment only. Self-reported diabetes prevalence was 0.1, 3.2, and 11.6% in the age groups 70 yr, respectively. CONCLUSIONS The prevalence of diabetes in Brazil is comparable with that of more developed countries, where it is considered a major health problem.

Molecular genetics of steroid 5α-reductase 2 deficiency

Abstract: Two isozymes of steroid 5 alpha-reductase encoded by separate loci catalyze the conversion of testosterone to dihydrotestosterone. Inherited defects in the type 2 isozyme lead to male pseudohermaphroditism in which affected males have a normal internal urogenital tract but external genitalia resembling those of a female. The 5 alpha-reductase type 2 gene (gene symbol SRD5A2) was cloned and shown to contain five exons and four introns. The gene was localized to chromosome 2 band p23 by somatic cell hybrid mapping and chromosomal in situ hybridization. Molecular analysis of the SRD5A2 gene resulted in the identification of 18 mutations in 11 homozygotes, 6 compound heterozygotes, and 4 inferred compound heterozygotes from 23 families with 5 alpha-reductase deficiency. 6 apparent recurrent mutations were detected in 19 different ethnic backgrounds. In two patients, the catalytic efficiency of the mutant enzymes correlated with the severity of the disease. The high proportion of compound heterozygotes suggests that the carrier frequency of mutations in the 5 alpha-reductase type 2 gene may be higher than previously thought.

Chemical stratigraphy of the Paraná lavas (South America): classification of magma types and their spatial distribution

Abstract: A new classification scheme has been developed to assign the lava flows of the Parana continental flood basalt province (South America) into geochemically distinct magma types, with six basaltic major and trace element abundances and/or ratios. By mapping out the spatial distribution of these magma types within the lava sequences, it has been possible to determine the internal stratigraphy of the lava pile on a regional scale. Previous studies on road profiles traversing the well-exposed coastal Serra Geral escarpment of southern Brazil are summarised together with results from some new sampled sections. More widespread stratigraphical investigations of the Parana lavas have been hampered by the lack of sufficient topographic relief and the cover of sedimentary rocks. However, access to drill-core chippings from nine boreholes in the central Parana region has provided a unique opportunity to investigate the stratigraphy of the otherwise inaccessible deeper levels of the lava pile and to map out stratigraphic variations in three dimensions. The borehole samples have indicated cated a stacking of units of different magma types all overlapping towards the north, which suggests that the main locus of magmatism moved northwards with time within the Parana basin. This migration could be related to the northward propagation of rifting during the initiation of the South Atlantic Ocean. Maps of the surface distribution of samples of each magma type show a pattern consistent with the stratigraphy inferred from the boreholes, although suggesting that the shift in magmatism may have been towards the northwest. On the basis of geochemical similarities between magma types and their inferred stratigraphical relationships, it is proposed that the Parana can be divided into two principal magmatic centres: (1) an older one in the south, comprising the Gramado, Esmeralda and Urubici magma types; and (2) a younger one, developed about 750 km to the north, formed by the Pitanga, Paranapanema and Ribeira magma types.

Persistent blood pressure increase induced by heavy smoking.

Abstract: Objective: To test the hypothesis that heavy smoking is associated with a persistent increase in blood pressureDesign: In 10 normotensive smokers asked to smoke one cigarette every 15 min for 1 h, blood pressure and heart rate were continuously monitored during the smoking period and during the prec

Glutamate release in experimental ischaemia of the retina: an approach using microdialysis.

Abstract: A rabbit eye model of neural ischaemia is described that uses an increased pressure in the anterior eye chamber to block the capillary supply to the retina. A microdialysis probe placed very close to the retinal surface was used to monitor release of amino acids during ischaemia. A large (two- to threefold) increase in the release of glutamate and O-phosphoserine (twofold), but not of six other amino acids monitored, occurred during initial ischaemia. During reperfusion after release of intraocular pressure, much larger (five- to 10-fold) increases in the release of these amino acids were observed. Parallel ischaemic retinal tissue damage was observed. This damage was prevented by keta-mine applied locally via a superfusion needle, suggesting that glutamate released during ischaemia, and particularly during reperfusion, was responsible for cell death.

Singlet oxygen induced DNA damage.

Abstract: Singlet oxygen generated by photoexcitation and by chemiexcitation selectively reacts with the guanine moiety in nucleosides (kq + kr about 5 x 10(6) M-1s-1) and in DNA. The oxidation products include 8-oxo-7-hydro-deoxyguanosine (8-oxodG; also called 8-hydroxydeoxyguanosine) and 2,6-diamino-4-hydroxy-5-formamidopyrimidine (FapyGua). Singlet oxygen also causes alkali-labile sites and single-strand breaks in DNA. The biological consequences include a loss of transforming activity as studied with plasmids and bacteriophage DNA, and mutagenicity and genotoxicity. Employing shuttle vectors, it was shown that double-stranded vectors carrying singlet oxygen induced lesions seem to be processed in mammalian cells by DNA repair mechanisms efficient in preserving the biological activity of the plasmid but highly mutagenic in mammalian cells. Biological protection against singlet oxygen is afforded by quenchers, notably carotenoids and tocopherols. Major repair occurs by excision of the oxidized deoxyguanosine moieties by the Fpg protein, preventing mismatch of 8-oxodG with dA, which would generate G:C to T:A transversions.

Surgical anatomy of the external branch of the superior laryngeal nerve.

Abstract: Iatrogenic lesions of the external branch of the superior laryngeal nerve (EBSLN) during thyroidectomies are not infrequent due to the possibility of anatomic variations of the relationships of this nerve with the superior thyroid vessels. Therefore, based on an anatomic analysis of 30 superior thyroid poles from 15 fresh cadavers, a new classification of the EBSLN was proposed, considering the jeopardy during a thyroidectomy. Thirty-seven percent of the nerves were type 2, ie, crossing the superior thyroid pedicle less than 1 cm above the superior thyroid pole. It is notable that 20% were type 2b, ie, crossing the vessels below the upper border of the pole, having been considered "high risk." This incidence was comparable with other series, which found dangerous anatomic variations of the EBSLN in the range of 15% to 68%, confirming that a significant proportion of these nerves might be at risk during surgery on the superior thyroid pole.

Corona charging of polymers

Abstract: A review of the corona charging of polymers is presented. After providing a brief account of the corona discharge process and of its application for charging materials, the paper focuses on the evolution of corona triodes that allow the sample surface potential to be monitored during the charging process. Particular emphasis is given to the main contributions arising from research, basically on Teflon FEP and ferroelectric polymers, in which a constant-current corona triode was used. Such a triode system has become a powerful tool in the study of charge transport and ferroelectric properties of polymers, because keeping the charging current constant facilitates matching of the experimental results to a number of theoretical models. >

Therapy for Neurocysticercosis: Comparison Between Albendazole and Praziquantel

Abstract: • Praziquantel and albendazole have been recently described as effective drugs for treatment of intraparenchymal brain cysticercosis. We performed a prospective study comparing the efficacy of these drugs. Twenty-two patients were treated with praziquantel and 21 with albendazole. In addition, 16 patients were treated with symptomatic drugs only and used as controls. Treatment was discontinued in two patients receiving praziquantel and one patient receiving albendazole owing to acute decompensation of the increased intracranial pressure, and one of them died. Albendazole and praziquantel were effective when compared with the control group. However, albendazole was significantly more effective than praziquantel in reducing the total number of cysts in the computed tomographic scans (88% vs 50%). Despite these results, however, analysis of clinical course showed a high frequency of neurologic sequelae. Considering the risks and fallibility of anticysticercal therapy, the real solution for this serious disease continues to be prophylaxis of infestation.

Renal denervation normalizes pressure and baroreceptor reflex in high renin hypertension in conscious rats.

Abstract: High renin hypertension is usually accompanied by impairment of the baroreceptor reflexes. This feature has been mostly ascribed to overactivity of the renin-angiotensin system. However, renal nerves could also modulate the baroreceptor reflexes. In the present experiments, the effect of renal denervation on the depressed baroreceptor reflexes was studied in rats subjected to aortic ligation between the renal arteries. Renal denervation of the ischemic kidney was performed at the same time as aortic ligation. The resulting effects on arterial pressure, heart rate, plasma renin activity, and baroreceptor reflex control of heart rate were studied 10-12 days after ligation and denervation. Aortic ligation induced high levels of mean arterial pressure (166 +/- 6 versus 110 +/- 3 mm Hg in controls), heart rate (380 +/- 9 versus 352 +/- 8 beats per minute in controls), and plasma renin activity (44 +/- 5 versus 6 +/- 1.2 ng angiotensin I/ml/hr). The baroreceptor reflex sensitivity for bradycardia and tachycardia was significantly reduced (-0.18 +/- 0.04 and -0.18 +/- 0.05, respectively, versus -2.3 +/- 0.01 and -2.4 +2- 0.1 beats per minute per mm Hg in controls). Denervation of the ischemic kidney attenuated the development of hypertension in aortic-ligated rats (122 +/- 3 mm Hg), lowering heart rate (319 +/- 8 beats per minute) and normalizing baroreceptor reflex sensitivity to bradycardia (-2.0 +/- 0.2 beats per minute per mm Hg) and to tachycardia (-4.0 +/- 0.1 beats per minute per mm Hg). Plasma renin activity was also normalized (4.3 +/- 2.4 ng angiotensin I/ml/hr).(ABSTRACT TRUNCATED AT 250 WORDS)

BCS1, a novel gene required for the expression of functional Rieske iron-sulfur protein in Saccharomyces cerevisiae

Abstract: Respiratory deficient pet mutants of Saccharomyces cerevisiae assigned to complementation group G2 define a new gene, named BCS1, whose product is shown to be necessary for the expression of functional ubiquinol-cytochrome c reductase (bc1) complex. Immunological assays indicate a gross reduction in the Rieske iron-sulfur subunit in bcs1 mutants, while other subunits of the ubiquinol-cytochrome c reductase complex are present at concentrations comparable to the wild type. Transformation of bcs1 mutants with the iron-sulfur protein gene on a multicopy plasmid led to elevated mitochondrial concentrations of Rieske protein, but did not correct the enzymatic defect, indicating that BCS1 is involved either in forming the active site iron-sulfur cluster or providing a chaperone-like function in assembling the Rieske protein with the other subunits of the complex. Both postulated functions are consistent with the localization of BCS1 in mitochondria. To facilitate further studies on this novel protein, BCS1 was cloned by transformation of a bcs1 mutant and its structure determined. The primary structure of the encoded BCS1 protein bears similarity to a group of proteins that have been implicated in intracellular protein sorting, membrane fusion and regulation of transcription. The region of BCS1 homologous to this diverse group of proteins is approximately 200 amino acids long and includes several signature sequences commonly found in ATPases and nucleotide binding proteins.

Morphological Classification of galaxies by Artificial Neural Networks

Abstract: We explore a method for automatic morphological classification of galaxies by an Artificial Neural Network algorithm. The method is illustrated using 13 galaxy parameters measured by machine (ESO-LV), and classified into five types (E, SO, Sa + Sb, Sc + Sd and Irr). A simple Backpropagation algorithm allows us to train a network on a subset of the catalogue according to human classification, and then to predict, using the measured parameters, the classification for the rest of the catalogue. We show that the neural network behaves in our problem as a Bayesian classifier, i.e. it assigns the a posteriori probability for each of the five classes considered. The network highest probability choice agrees with the catalogue classification for 64 per cent of the galaxies. If either the first or the second highest probability choice of the network is considered, the success rate is 90 per cent. The technique allows uniform and more objective classification of very large extragalactic data sets.

Shock fluctuations in asymmetric simple exclusion

Abstract: The one dimensional nearest neighbors asymmetric simple exclusion process in used as a microscopic approximation to the Burgers equation. We study the process with rates of jumpsp>q to the right and left, respectively, and with initial product measure with densities ϱ<λ to the left and right of the origin, respectively (with shock initial conditions). We prove that a second class particle added to the system at the origin at time zero identifies microscopically the shock for all later times. If this particle is added at another site, then it describes the behavior of a characteristic of the Burgers equation. For vanishing left density (ϱ=0) we prove, in the scale t1/2, that the position of the shock at timet depends only on the initial configuration in a region depending ont. The proofs are based on laws of large numbers for the second class particle.

Morphologic study of the maxillary molars. Part II: Internal anatomy.

Abstract: The internal anatomy of three hundred and seventy (370) decalcified and cleared human maxillary molars was studied. Seventy-five percent of the first molars, 58% of the second molars and 68% of the third molars studied presented three (3) root canals and 25% of the first molars, 42% of the second molars and 32% of the third molars presented four (4) root canals. The authors observed that the incidence of two root canals in the mesiobuccal root was higher in second maxillary molars than in first maxillary molars.

Myocardial perfusion abnormalities in chronic Chagas' disease as detected by thallium-201 scintigraphy☆

Abstract: Most patients with chronic Chagas' heart disease complain of chest pain. The pathophysiology of this symptom is unknown, although myocardial necrosis and fibrosis are frequent necropsy findings and cardiac autonomic impairment is a prominent feature of the disease. To evaluate the possibility of an ischemic cause for these abnormalities in 23 patients (18 men, aged 32 to 60 years, mean 42) with chronic Chagas' disease complaining of chest pain, thallium-201 myocardial scintigraphy was performed after maximal effort and 4-hour redistribution. Regional wall motion was assessed by radionuclide and contrast angiography. Heart rate responses to sinus respiratory arrhythmia, atropine, phenylephrine and Valsalva maneuver were evaluated in all patients and in 22 normal control subjects. Coronary angiography was performed in 16 patients. Only 1 patient had chest pain and no ischemic electrocardiographic changes occurred in any case during the effort test. Scintigraphic analysis of 7 segments per patient showed perfusion defects in at least 1 segment in all patients. Of 161 myocardial segments 16 showed fixed, 10 reversible, and 22 paradox defects (reverse redistribution). The majority (75%) of the fixed perfusion defects occurred in dyssynergic regions, whereas reverse redistribution predominated in regions with normal wall motion (82%). The reversible defects were present in normal or mildly hypokinetic regions. Markedly impaired parasympathetic cardiac control was present but no significant coronary abnormalities were seen in any of the 16 patients undergoing angiography. It is concluded that whereas fixed defects are likely to correspond to fibrotic or necrotic lesions, reversible and paradox perfusion defects may be caused by regional flow or metabolism derangements, possibly related to abnormal parasympathetic control of the coronary microcirculation.

Near-barrier fusion of Li 11 with heavy spherical and deformed targets

Abstract: The cross sections for the fusion of $^{11}\mathrm{Li}$ with $^{208}\mathrm{Pb}$ and $^{238}\mathrm{U}$ are calculated at near-barrier energies. The coupling of the entrance channel to the soft giant dipole resonance in $^{11}\mathrm{Li}$ is taken into account together with the coupling to the breakup channel $^{9}\mathrm{Li}$+2n. The deformation of $^{238}\mathrm{U}$ is also considered. The cross section is found to exhibit important structure around the barrier.

Basolateral amygdala lesions block diazepam-induced anterograde amnesia in an inhibitory avoidance task.

Abstract: This experiment examined the effects of diazepam (DZP) on acquisition and retention of an inhibitory avoidance response by rats with excitotoxic-induced lesions of central (CE), lateral (LAT), or basolateral (BL) amygdala nuclei. Sham-operated and lesioned rats received i.p. injections of DZP (2.0 mg per kg of body weight) 30 min before training in a continuous multiple-trial inhibitory avoidance task. Retention was tested 48 h later. Acquisition was not impaired by the lesions or the DZP. Retention was impaired in animals with CE and LAT lesions in comparison with sham-operated controls. DZP impaired retention in the sham-operated controls as well as CE- and LAT-lesioned animals but did not affect retention in animals with BL lesions. These findings indicate that the DZP-induced anterograde amnesia for inhibitory avoidance training is mediated through influences involving the BL amygdala nucleus.

Biochemical and immunological characterization of p190-calmodulin complex from vertebrate brain: a novel calmodulin-binding myosin.

Abstract: We have recently identified a novel 190-kD calmodulin-binding protein (p190) associated with the actin-based cytoskeleton from mammalian brain (Larson, R. E., D. E. Pitta, and J. A. Ferro. 1988. Braz. J. Med. Biol. Res. 21:213-217; Larson, R. E., F. S. Espindola, and E. M. Espreafico. 1990. J. Neurochem. 54:1288-1294). These studies indicated that p190 is a phosphoprotein substrate for calmodulin-dependent kinase II and has calcium- and calmodulin-stimulated MgATPase activity. We now have biochemical and immunological evidence that this protein is a novel calmodulin-binding myosin whose properties include (a) Ca2+ dependent action activation of its Mg-ATPase activity, which seems to be mediated by Ca2+ binding directly to calmodulin(s) associated with p190 (maximal activation by actin requires the presence of Ca2+ and is further augmented by addition of exogenous calmodulin); (b) ATP-sensitive cross-linking of skeletal muscle F-actin, as demonstrated by the low-speed actin sedimentation assay; and (c) cross-reactivity with mAbs specific for epitopes in the head of brush border myosin I. We also show that p190 has properties distinct from conventional brain myosin II and brush border myosin I, including (a) separation of p190 from brain myosin II by gel filtration on a Sephacryl S-500 column; (b) lack by p190 of K(+)-stimulated EDTA ATPase activity characteristic of most myosins; (c) lack of immunological cross-reactivity of polyclonal antibodies which recognize p190 and brain myosin II, respectively; (d) lack of immunological recognition of p190 by mAbs against an epitope in the tail region of brush border myosin I; and (e) distinctive proteolytic susceptibility to calpain. A survey of rat tissues by immunoblotting indicated that p190 is expressed predominantly in the adult forebrain and cerebellum, and could be detected in embryos 11 d post coitus. Immunocytochemical studies showed p190 to be present in the perikarya and dendritic extensions of Purkinje cells of the cerebellum.

The source of the growth-promoting factor(s) affects the plating efficiency of Paracoccidioides brasiliensis.

Abstract: We studied the influence of the growth factor (GF) source, concentration and production time on the plating efficiency of Paracoccidioides brasiliensis yeast cells. The highest plating efficiencies were achieved when the GF was derived from a fast growing P. brasiliensis isolate which was not homologous to the plated samples.

Estudo da ocorrência de enteroparasitas em hortaliças comercializadas na região metropolitana de São Paulo, SP, Brasil: I - Pesquisa de helmintos

Abstract: Hortalicas in natura, comercializadas na regiao metropolitana de Sao Paulo, SP (Brasil), foram analisadas atraves de metodologia propria, visando a pesquisa e a identificacao de formas de transmissao de helmintos intestinais de interesse medico. As hortalicas examinadas, constituidas de 50 amostras de cada variedade, foram de: alface (Lactuca sativa), variedades lisa e crespa, escarola (Chichorium sp) e agriao (Nasturtium officinale). Os resultados evidenciaram elevados percentuais de contaminacao em todas as variedades analisadas, porem, as frequencias de helmintos foram maiores no agriao. A escarola apresentou valores medios, geralmente situados entre as alfaces e o agriao. Os numeros medios de ovos e larvas por 100 gramas de amostra, embora elevados, nao apresentaram diferencas estatisticamente significantes entre as quatro variedades de hortalicas estudadas. Uma grande variedade de helmintos, de ocorrencia frequente na populacao residente na Regiao Metropolitana de Sao Paulo, foi observada nas amostras. Os mais frequentes, no entanto, foram: ancilostomideos e Ascaris sp. Recuperaram-se tambem ovos de Toxocara sp, Fasciola sp e de tricostrongilideos, comprovando a ocorrencia de contaminacao das hortalicas por fezes de animais domesticos. Considerando-se os resultados obtidos, ressalta-se a importância das hortalicas na transmissao de helmintiases intestinais, bem como a necessidade de medidas que propiciem uma melhoria na qualidade higienico-sanitaria destes alimentos.

Root form and canal anatomy of maxillary first premolars.

Abstract: The external and internal anatomy of 240 extracted, maxillary first premolars was studied. The external anatomy was studied by measuring each tooth and by observing the direction of the root curvatures from the facial and proximal aspects. The internal anatomy of the pulp cavity was studied by a method of making the teeth translucent. A total of 55.8% of the teeth had a single root, 41.7% had two roots and 2.5% had three roots. Considering all of the first premolars, 17.1% had one canal, 80.4% had two canals and 2.5% had three canals.

The complications of infective endocarditis. A reappraisal in the 1980s.

Abstract: Background.— The frequency of complications of infective endocarditis and their influence on the outcome of the patients changed in the antibiotic era. Therefore, we evaluated the complications in a recent large series of patients with infective endocarditis. Methods.— We studied 300 episodes of endocarditis in 287 patients in a tertiary cardiology referral center. Predisposing cardiac conditions were valvular heart disease in 147 episodes, congenital heart disease in 37, other heart diseases in five, and prosthetic heart valves in 69. In 69 episodes, there was no previous heart disease. The infecting microorganisms were streptococci in 147 episodes, Staphylococcus aureusin 59,Staphylococcus epidermidisin 14, gram-negative bacteria in 16, other gram-positive bacteria in eight, and fungi in four. In 52 episodes, blood cultures were negative. Seventy-eight patients (26%) died. Complications were defined as any clinically unfavorable event occurring during treatment. Results.— A total of 386 complications occurred in 223 episodes (74%); one complication occurred in 128 episodes (57%), two in 57 (26%), three in 18 (8%), four in 13 (6%), five in three (1%), and six or more in three (1%), The complications were as follows: cardiac, 100 occurrences; neurological, 72; septic, 46; associated with medical treatment, 41; renal, 27; extracranial systemic arterial embolism, 16; septic pulmonary embolism, 26; complications related to surgical treatment, 11; acute prosthetic heart valve insufficiency, six; splenic infarction or abscess, three; cardiac rhythm disturbances, three; and other, 19. The distribution of the complications relative to outcome of the patients revealed that fatality exceeded survival rates for neurologic and septic complications. Conclusions.— Complications may be common in patients with infective endocarditis. Cardiac complications were the most common ones, but fatality rates were higher for neurologic and septic complications. Hence, heart failure was replaced by neurologic and septic complications as the leading causes of death in patients with infective endocarditis. (Arch Intern Med.1992;152:2428-2432)