The impact of the COVID-19 pandemic on TB diagnosis in the Brazilian prison population, 2020-2021.

BACKGROUND: TB is an infectious disease with a worldwide impact. TB is closely associated with social and housing conditions, exerting a significant impact on the prison population, which is particularly susceptible to the disease. Evidence suggests that the COVID-19 pandemic has exacerbated social vulnerability. This study therefore aimed to analyse the impact of the pandemic on the diagnosis of new cases of TB in the Brazilian prison population in the years 2020 and 2021.METHODS: This is an ecological study involving cases of TB recorded in the prison population of Brazil from 2015 to 2021. Data were collected from the Brazil's Information System for Notifiable Diseases.RESULTS: The incidence of TB in the prison population in Brazil fell from 1,005.9/100,000 population between 2015 and 2019 to 852.3/100,000 population between 2020 and 2021. In 2021, there was a deficit of 539 cases (-7.6%) compared to what was expected for the year. In 2020, there was a 10% reduction in TB diagnoses in January and February, reaching 3.8% in March. A negative percentage was observed in most of the subsequent months. In 2021, the year began with a 21.6% decline in January, returning to positive values only in August and September.CONCLUSION: The first years of the COVID-19 pandemic resulted in underdiagnosis of TB in the Brazilian prison population.

A novel BSA immobilizing manner on modified titanium surface ameliorates osteoblast performance.

Surface modification of medical and dental devices, to improve their biocorrosion resistance and biocompatibility, can be achieved with the multidisciplinary field of biomaterials. Nanostructured titanium dioxide (TiO2) has been employed as surface modifier of titanium-based biomaterials because it can prevent the failure of the devices due to wear mechanisms. Moreover, this oxide surface is mostly terminated by hydroxyl groups (-OH) that can be directly functionalized with biomolecules to improve the biocompatibility of these devices. We explored the influence of 3-aminopropyltrimethoxysilane (APTMS) molecules as spacers in bovine serum albumin (BSA) protein immobilization on the physically hydroxylated surfaces of rutile phase TiO2 films grown by reactive Radio Frequency (RF) magnetron sputtering. X-ray Photoelectron Spectroscopy (XPS) was used to examine the adsorption of BSA and APTMS on the hydroxylated surface of TiO2 thin films. For biological tests, BSA was directly immobilized on the film surface and on the APTMS monolayer. Biological analysis found better osteoblast performance considering gene markers related to cell adhesion after interacting directly with the surface modified by the immobilization of BSA, especially on the surface where this protein was immobilized by APTMS. Additionally, we addressed the relevance of this biointerfaces on extracellular matrix remodeling by zymography analysis. Altogether, our data provides new insights about the cellular and molecular mechanisms covering the improved osteoblastic response of the proposed surface modification.

Nematic liquid crystal in a cylindrical sample: Theoretical analysis of the electrical response.

The electrical responses of a nematic liquid crystal sample confined between two cylindrical surfaces are investigated in the framework of elastic continuum theory. The responses are the result of the molecular reorientation induced by both the applied electric field and the cylindrical geometry of the sample. The nematic medium is considered as a parallel RC circuit since the capacitance and the resistance are under the same difference of potential. The electrical properties, including the total electric current, are determined from the molecular reorientation of the director. The elastic anisotropy has been shown to influence substantially the profile of the electrical current, capacitance, and resistance characterizing the equivalent circuit for the medium.

Elastic anisotropy effects on the electrical responses of a thin sample of nematic liquid crystal.

The electrical responses of a nematic liquid crystal cell are investigated by means of the elastic continuum theory. The nematic medium is considered as a parallel circuit of a resistance and a capacitance and the electric current profile across the sample is determined as a function of the elastic constants. In the reorientation process of the nematic director, the resistance and capacitance of the sample are determined by taking into account the elastic anisotropy. A nonmonotonic profile for the current is observed in which a minimum value of the current may be used to estimate the elastic constants values. This scenario suggests a theoretical method to determine the values of the bulk elastic constants in a single planar aligned cell just by changing the direction of applied electrical field and measuring the resulting electrical current.

Use of a Direct Anatomic Post in a Flared Root Canal: A Three-year Follow-up.

The following case report describes the three-year follow-up after rehabilitation of a flared root canal using a direct anatomic post (a resin composite combined with a prefabricated glass fiber post) associated with metal-free ceramic restoration. The report presents the clinical protocol for the fabrication of the posts, which provide an intimate fit to the remaining root and mechanical properties similar to those of the dental structure. These posts serve as an alternative to conventional metal cores.

Effect of operator experience on the outcome of fiber post cementation with different resin cements.

OBJECTIVES: To evaluate the influence of operator experience (dentist vs student) and cementation system (Adper Scotchbond Multi-Purpose [SBMP] + RelyX ARC [1]; Adper Single Bond 2 [SB] + RelyX ARC [2] and RelyX U100 [3]) on the push-out bond strength (BS) of fiber post to radicular dentin. MATERIALS AND METHODS: The roots of 48 extracted human maxillary central incisors were prepared and divided into six groups (n=8), according to combination of the above factors. Glass fiber posts were cemented in accordance with the instructions of the manufacturer of each cementation system. After water storage at 37°C for one week, the roots were cross-sectioned into six 1-mm thick slices and the push-out test was performed (0.5 mm/min). Data were statistically analyzed by two-way analysis of variance and Tukey tests (α=0.05). The BS results obtained by dentist and student for each cementation system were compared using the Student t-test (α=0.05). RESULTS: Higher BS means were observed for the expert operators, irrespective of the cementation system used (p=0.006). RelyX U100 showed the highest bond strength, but it did not differ from SBMP + RelyX ARC. The Student t-test revealed that only RelyX U100 was not affected by the operator's experience. CONCLUSION: Within the limitations of this in vitro study, it can be concluded that the self-adhesive cement RelyX U100 showed the highest bond strength to the root canal in the student's group, and its performance was not affected by the operator's experience.

Rede Paulista de Avaliação de Tecnologias de Saúde: primeiros passos / São Paulo State Health Technology Assessment Network: first steps

A avaliação de tecnologias de saúde é método para estudar produtos, programas e estratégias visando subsidiar decisões para incorporar inovações, usá-las, justificar reformas ou aperfeiçoar melhorias. O Estado de São Paulo está multiplicando sua capacidade de avaliar tecnologias de saúde com o propósito de aprimorar o planejamento do SUS-SP pela integração dos hospitais nas instâncias de gestão estadual e local. A Rede Paulista de ATS já compreende 33 hospitais na SES-SP e outras instituições, contando com mais de uma centena de profissionais aptos.

Deleterious effect of hypothermia in myocardial protection against cold ischemia: a comparative study in isolated rat hearts.

BACKGROUND: There is a growing need to improve heart preservation benefit the performance of cardiac operations, decrease morbidity, and more important, increase the donor pool. Therefore, the objective of this study was to evaluate the cardioprotective effects of Krebs-Henseleit buffer (KHB), Bretschneider-HTK (HTK), St. Thomas No. 1 (STH-1), and Celsior (CEL) solutions infused at 10°C and 20°C. METHODS: Hearts isolated from male albino Wistar rats and prepared according to Langendorff were randomly divided equally into 8 groups according to the temperature of infusion (10°C or 20°C) and cardioprotective solutions (KHB, HTK, STH-1, and CEL). After stabilization with KHB at 37°C, baseline values were collected (control) for heart rate (HR), left ventricle systolic pressure (LVSP), coronary flow (CF), maximum rate of rise of left ventricular pressure during ventricular contraction (+dP/dt) and maximum rate of fall of left ventricular pressure during left ventricular relaxation (-dP/dt). The hearts were then perfused with cardioprotective solutions for 5 minutes and kept for 2 hours in static ischemia at 20°C. Data evaluation used analysis of variance (ANOVA) in all together randomized 2-way ANOVA and Tukey's test for multiple comparisons. The level of significance chosen was P < .05. RESULTS: We observed that all 4 solutions were able to recover HR, independent of temperature. Interestingly, STH-1 solution at 20°C showed HR above baseline throughout the experiment. An evaluation of the corresponding hemodynamic values (LVSP, +dP/dt, and -dP/dt) indicated that treatment with CEL solution was superior at both temperatures compared with the other solutions, and had better performance at 20°C. When analyzing performance on CF maintenance, we observed that it was temperature dependent. However, when applying both HTK and CEL, at 10°C and 20°C respectively, indicated better protection against development of tissue edema. Multiple comparisons between treatments and hemodynamic variable outcomes showed that using CEL solution resulted in significant improvement compared with the other solutions at both temperatures. CONCLUSION: The solutions investigated were not able to fully suppress the deleterious effects of ischemia and reperfusion of the heart. However, these results allow us to conclude that temperature and the cardioprotective solution are interdependent as far as myocardial protection. Although CEL solution is the best for in myocardial protection, more studies are needed to understand the interaction between temperature and perfusion solution used. This will lead to development of better and more efficient cardioprotective methods.

Comparative analysis of the performance of various crystalloid cardioplegic solutions on myocardial protection after prolonged cold ischemia.

INTRODUCTION: The quality and effectiveness of myocardial protection are fundamental problems to expand the use of and consequently good outcomes of donated hearts for transplantation. OBJECTIVE: The purpose of this investigation was to compare the cardioprotective effects of Krebs-Henseleit, Bretschneider-HTK, St Thomas, and Celsior solutions using a modified nonrecirculating Langendorff column model of isolated perfused rat heart during prolonged cold storage. MATERIALS AND METHODS: After removal 36 rat hearts underwent isolated perfusion into a Langendorff apparatus using Krebs-Henseleit solution for a 15-minute period of recovery; we excluded organs that did not maintain an aortic pressure above 100 m Hg. Subsequently, we equally distributed the hearts into four groups according to the cardioprotection solution; group 1, Krebs-Henseleit (control); group II, Bretschneider-HTK; group III, St Thomas; and group IV, Celsior. Each heart received the specific cardioplegic solution at 10°C for 2-hour storage at 20°C, before a 15 minutes perfusion with Krebs-Henseleit solution for recovery and stabilization. After 60 additional minutes of perfusion, every 5 minutes we determined heart rate (HR), coronary flow (CF), left ventricular systolic pressure (LVSP), and positive and negative peak of the first derivative of left ventricular pressure (+dP/dt and -dP/dt, respectively). RESULTS: Comparative analysis by Turkey's test showed the following performances among the groups at 60 minutes of reperfusion: HR: II = IV > III > I; CF: II = IV > I = III; LVSP: IV > I = II = III; +dP/dt: IV > I = II = III; and -dP/dt: IV = II > I = II. CONCLUSION: Cardioprotective solutions generally used in clinical practice are not able to avoid hemodynamic alterations in hearts exposed to prolonged ischemia. Celsior solution showed better performance than Bretschneider-HTK, St Thomas, and Krebs-Henseleit.

Effect of water storage on resin-dentin bond strengths formed by different bonding approaches.

OBJECTIVES: The purpose of this study was to evaluate the influence of water storage on resin-dentin bond strengths [microTBS] using different adhesive bonding approaches. MATERIALS AND METHODS: Flat superficial dentin surfaces of 24 extracted human third molars were exposed and polished to create a standardized smear layer. The teeth were randomly distributed into four different groups: Three-step etch-and-rinse (Adper Scotchbond Multi-Purpose, 3M ESPE-SBMP), two-step etch-and-rinse (Adper Single Bond 2, 3 M ESPE-SB); two-step self-etch (AdheSE, Ivoclar/Vivadent-AD); and self-etch 1 step (Adper Prompt L-Pop, 3M ESPE-LP). Following the adhesive application (n = 6), resin composite was incrementally applied (Filtek Supreme XT-3 M ESPE) in order to obtain bonded sticks, with a cross-sectioned area of 0.81 mm2. The bonded sticks were randomly divided and assigned to be tested after one day [OD] (n 30) or six months [6 M] of water storage [6 M] (n = 30). RESULTS: Two-way ANOVA and Tukey's test showed that none of the adhesives showed degradation after 6 M. SB achieved the highest microTBS both in the [OD] (49.13 MPa) and [6M] (40.27 MPa). Despite the highest values in both time evaluations, the microTBS of SB significantly reduced after 6M. LP showed the lowest microTBS in both periods of evaluation (18.35 and 18.34 MPa). CONCLUSIONS: Although a significant degradation was only observed for SB, this was the adhesive that showed the highest microTBS after 6 M of water storage.

Influence of evoked compound action potential on speech perception in cochlear implant users.

UNLABELLED: Electrically Evoked Compound Action Potential is a measure of synchronous cochlear nerve fibers activity elicited by electrical stimulation of the cochlear implant. The electrophysiological nerve responses may contribute to explain the variability in individual performance of cochlear implant recipients. AIM: To compare speech perception tests performances of cochlear implant users according to the presence or absence of intraoperative neural telemetry responses. MATERIAL AND METHOD: Prospective study design with 100 "Nucleus 24" cochlear implant users divided in two groups according to the presence or absence of intraoperative neural telemetry responses. Speech perception tests were performed after 6 months of continuous use of the device and compared among groups. RESULTS: Intraoperative action potentials were observed in 72 % of individuals. Open-set sentence test results were better in implant users who had neural telemetry responses when compared to implant users in whom this potential was absent (averages 82.8 % versus 41 %, p = 0.005). There was a strong association between post meningitis-related deafness and absence of intraoperative potentials. CONCLUSION: The absence of intraoperative neural telemetry responses was associated with worse performances in speech perception tests and meningitis as etiology of deafness. On the other hand, the presence of these potentials suggests excellent prognosis.

Efeitos do potencial de ação neural sobre a percepção de fala em usuários de implante coclear / Influence of evoked compound action potential on speech perception in cochlear implant users

O Potencial de Ação Composto Evocado Eletricamente reflete a atividade do nervo auditivo, podendo ser registrado através dos eletrodos do implante coclear. A determinação dos elementos neurais estimuláveis pode contribuir para explicar a variabilidade de desempenho entre indivíduos implantados. OBJETIVO: Comparar o desempenho nos testes de percepção da fala entre pacientes que apresentaram e que não apresentaram potencial de ação composto evocado eletricamente no momento intra-operatório. MATERIAL E MÉTODO: Estudo prospectivo no qual 100 indivíduos usuários do implante coclear Nucleus 24 foram divididos em dois grupos de acordo com a presença ou ausência do potencial de ação intra-operatório. Após 6 meses de uso do dispositivo, os resultados dos testes de percepção de fala foram comparados entre os grupos. RESULTADOS: O potencial foi observado em 72 por cento dos pacientes. A percepção no teste de frases em formato aberto foi melhor nos indivíduos com presença de potencial (média 82,8 por cento contra 41,0 por cento, p = 0,005). Houve associação entre ausência do potencial e etiologia da surdez por meningite. CONCLUSÃO: Ausência de potencial neural intraoperatório esteve associada ao pior desempenho na percepção da fala e à etiologia da surdez por meningite. Por outro lado, a presença do potencial de ação intraoperatório sugere ótimo prognóstico.

Electrically Evoked Compound Action Potential is a measure of synchronous cochlear nerve fibers activity elicited by electrical stimulation of the cochlear implant. The electrophysiological nerve responses may contribute to explain the variability in individual performance of cochlear implant recipients. AIM: To compare speech perception tests performances of cochlear implant users according to the presence or absence of intraoperative neural telemetry responses. MATERIAL AND METHOD: Prospective study design with 100 "Nucleus 24" cochlear implant users divided in two groups according to the presence or absence of intraoperative neural telemetry responses. Speech perception tests were performed after 6 months of continuous use of the device and compared among groups. RESULTS: Intraoperative action potentials were observed in 72 percent of individuals. Open-set sentence test results were better in implant users who had neural telemetry responses when compared to implant users in whom this potential was absent (averages 82.8 percent versus 41 percent, p = 0.005). There was a strong association between post meningitis-related deafness and absence of intraoperative potentials. CONCLUSION: The absence of intraoperative neural telemetry responses was associated with worse performances in speech perception tests and meningitis as etiology of deafness. On the other hand, the presence of these potentials suggests excellent prognosis.

Lycopene and beta-carotene protect in vivo iron-induced oxidative stress damage in rat prostate.

It has been suggested that iron overload may be carcinogenic. In the present study, we evaluated the effect of plasma and prostate carotenoid concentration on oxidative DNA damage in 12-week-old Wistar rats treated with intraperitoneal (ip) ferric nitrilotriacetate (Fe-NTA) (10 mg Fe/kg). Plasma beta-carotene and lycopene concentrations were measured as a function of time after ip injection of carotenoids (10 mg kg(-1) day(-1) beta-carotene or lycopene) in rats. The highest total plasma concentration was reached 3 and 6 h after ip injection of lycopene or beta-carotene, respectively. After 5 days of carotenoid treatment, lycopene and beta-carotene were present in the 0.10-0.51 nmol/g wet tissue range in the prostate. Using a sensitive method to detected 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) by HPLC/EC, the level of 8-oxodGuo in rat prostate DNA was significantly higher (6.3 +/- 0.6 residues/10(6) dGuo) 3 h after Fe-NTA injection compared with control rats (1.7 +/- 0.3 residues/10(6) dGuo). Rats supplemented with lycopene or beta-carotene for 5 days prior to Fe-NTA treatment showed a reduction of about 70% in 8-oxodGuo levels to almost control levels. Compared with control rats, the prostate of Fe-NTA-treated animals showed a 78% increase in malondialdehyde accumulation. Lycopene or beta-carotene pre-treatment almost completely prevented lipid damage. Epidemiological studies have suggested a lower risk of prostate cancer in men reporting a higher consumption of tomato products. However, before associating this effect with tomato sauce constituents, more information is required. The results described here may contribute to the understanding of the protective effects of carotenoids against iron-induced oxidative stress.

Lycopene and ß-carotene protect in vivo iron-induced oxidative stress damage in rat prostate

It has been suggested that iron overload may be carcinogenic. In the present study, we evaluated the effect of plasma and prostate carotenoid concentration on oxidative DNA damage in 12-week-old Wistar rats treated with intraperitoneal (ip) ferric nitrilotriacetate (Fe-NTA) (10 mg Fe/kg). Plasma ß-carotene and lycopene concentrations were measured as a function of time after ip injection of carotenoids (10 mg kg-1 day-1 ß-carotene or lycopene) in rats. The highest total plasma concentration was reached 3 and 6 h after ip injection of lycopene or ß-carotene, respectively. After 5 days of carotenoid treatment, lycopene and ß-carotene were present in the 0.10-0.51 nmol/g wet tissue range in the prostate. Using a sensitive method to detected 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) by HPLC/EC, the level of 8-oxodGuo in rat prostate DNA was significantly higher (6.3 ± 0.6 residues/10(6) dGuo) 3 h after Fe-NTA injection compared with control rats (1.7 ± 0.3 residues/10(6) dGuo). Rats supplemented with lycopene or ß-carotene for 5 days prior to Fe-NTA treatment showed a reduction of about 70 percent in 8-oxodGuo levels to almost control levels. Compared with control rats, the prostate of Fe-NTA-treated animals showed a 78 percent increase in malondialdehyde accumulation. Lycopene or ß-carotene pre-treatment almost completely prevented lipid damage. Epidemiological studies have suggested a lower risk of prostate cancer in men reporting a higher consumption of tomato products. However, before associating this effect with tomato sauce constituents, more information is required. The results described here may contribute to the understanding of the protective effects of carotenoids against iron-induced oxidative stress.

Lycopene inhibits DNA damage and liver necrosis in rats treated with ferric nitrilotriacetate.

Experimental and epidemiological evidence suggests that lycopene, a carotenoid present in tomatoes, tomato products, and several fruits and vegetables, may play a role in preventing certain cancers in humans. We have investigated the effect of lycopene pretreatment on lipid peroxidation, oxidative damage to DNA, and histopathological changes in liver of animals subjected to intraperitoneal (ip) ferric nitrilotriacetate (Fe-NTA) administration. Compared with control rats, liver of Fe-NTA-treated animals showed a significant increase in the 8-oxo-7,8-dihydro-2'-deoxyguanosine level and a 75% increase in malondialdehyde accumulation concomitant with histopathological changes. Five days of lycopene pretreatment (10 mg/kg body weight, ip) almost completely prevented liver biomolecule oxidative damage and protected the tissue against the observed histological alterations.

Anomalous capillary length in cellular nematic-isotropic interfaces.

The long-standing puzzle of why capillary lengths measured in cellular nematic-isotropic interfaces are much longer than the value of 0.05 A predicted by Mullins-Sekerka theory has been solved. The resolution of the paradox is that in confined systems the substrate-nematic anchoring energy contributes to the capillary length which is greatly increased by selective adsorption of ions on the substrate.

Cocaine-related acute subdural hematoma: an emergent cause of cerebrovascular accident.

A case of "spontaneous" acute subdural hematoma caused by cocaine abuse is described. As an isolated cerebrovascular event, related to cocaine abuse, this is the first report in the literature. It also represents a new differential diagnosis for nontraumatic acute subdural haematomas. The putative pathophysiology of the lesion is discussed.

trans,trans-2,4-decadienal-induced 1,N(2)-etheno-2'-deoxyguanosine adduct formation.

A number of ring-extended DNA adducts resulting from the reaction of alpha,beta-unsaturated aldehydes, or their epoxides, with DNA bases have been characterized in recent years. These adducts may lead to miscoding during DNA replication, resulting, if not repaired, in mutations that can contribute to cancer development. trans,trans-2, 4-Decadienal (DDE) is one of the highly cytotoxic aldehydes endogenously formed from lipid peroxidation. To evaluate its DNA damaging potential, we have investigated the reaction of DDE with 2'-deoxyguanosine (dGuo) in the presence of peroxides. Three stable adducts were isolated by reverse-phase HPLC. Adduct A1, 3-(2-deoxy-beta-D-erythro-pentafuranosyl)-5,9-dihydro-9H-imidazo[2 , 1-i]purin-9-hydroxy, is a tautomer of 1, N(2)-etheno-2'-deoxyguanosine, a well-known reaction product of epoxy aldehydes with dGuo. Two new diasteroisomeric products, A2-1 and A2-2, 1-¿[3-(2'-deoxy-beta-D-erythro-pentafuranosyl)-5, 9-dihydro-9H-imidazo[2,1-i]purin-9-hydroxy]-7-yl¿-2-one-3-octanol, were isolated and characterized on the basis of their spectroscopic features as 1,N(2)-etheno adducts possessing a carbon side chain with a carbonyl and a hydroxyl group. The proposed reaction mechanism for the formation of adducts A2 involves DDE double epoxidation and hydrolysis of the C4 epoxy group prior to nucleophilic addition of the exocyclic amino group of dGuo to C1 of the aldehyde, followed by cyclization via nucleophilic attack on the C2 epoxy group by N-1 and elimination of H(2)O. After treatment of calf thymus DNA with DDE, formation of adducts A1 and A2 was detected by the LC/ESI/MS-MS technique. These results can contribute to a better understanding of the chemical structures of adducts resulting from the reaction of aldehydes with nucleic acid bases, a necessary step in assessing the genotoxic risks associated with this class of compounds.

Experimental test of the Warren-Langer model in nematic-isotropic planar interfaces.

In a directional solidification apparatus, the recoil of the nonsteady planar nematic-isotropic interface of the liquid crystal 8CB doped with hexachloroethane was measured, for different pulling velocities. Results agree very well with the predictions of our two-sided extension of Warren and Langer's one-sided model [Phys. Rev. E 47, 2702 (1993)], therefore supporting the validity of their ansatz about the evolution of the dopant concentration field. From the comparison between experiment and theory we obtain values for the segregation and diffusion coefficients of hexachloroethane in 8CB comparable to those found in the literature and measured by other methods. Using the same procedure, we measured the value of the segregation coefficient of 8CB doped with water as a function of applied sinusoidal electric field perpendicular to the sample, along the homeotropic direction. The segregation coefficient increases with electric field. In addition, preliminary results on the cellular instability in this system show that the capillary length of the pattern also increases with electric field. To our knowledge, this is the first binary system with continuously tunable segregation coefficient and capillary length.

Volatile cardioplegia: fast normothermic cardiac arrest induction and recovery with halothane in isolated rat hearts.

To study the effect of halothane as a cardioplegic agent, ten Wistar rats were anesthetized by ether inhalation and their hearts were perfused in a Langendorff system with Krebs-Henseleit solution (36 degrees C; 90 cm H2O pressure). After a 15-min period for stabilization the control values for heart rate, force(T), dT/dt and coronary flow were recorded and a halothane-enriched solution (same temperature and pressure) was perfused until cardiac arrest was obtained. The same Krebs-Henseleit solution was reperfused again and the parameters studied were recorded after 1, 3, 5, 10, 20 and 30 min. Cardiac arrest occurred in all hearts during the first two min of perfusion with halothane-bubbled solution. One minute after reperfusion without halothane, the following parameters reported in terms of control values were obtained: 90.5% of control heart rate(266.9 +/- 43.4 to 231.5 +/- 71.0 bpm), 20.2% of the force (1.83 +/- 0.28 to 0.37 +/- 0.25 g), 19.8% of dT/dt (46.0 +/- 7.0 to 9.3 +/- 6.0 g/s) and 90.8% of coronary flow (9.9 +/- 1.5 to 9.4 +/- 1.5 ml/min). After 3 min of perfusion they changed to 99.0% heart rate (261.0 +/- 48.2), 98.9% force (1.81 +/- 0.33), 98.6 dT/dt (45.0 +/- 8.2) and 94.8% coronary flow (9.3 +/- 1.4). At 5 min 100.8% (267.0 +/- 40.6) heart rate, 105.0% (1.92 +/- 0.29) force and 104.4% (48.2 +/- 7.2) dT/dt were recorded and maintained without significant differences (P > 0.01) until the end of the experiment. These data demonstrate that volatile cardioplegia with halothane is an effective technique for fast induction of and prompt recovery from normothermic cardiac arrest of the rat heart.