Fitomassa de adubos verdes e controle de plantas daninhas em diferentes densidades populacionias de leguminosas.

O objetivo deste trabalho foi avaliar a fitomassa de calopogônio, mucuna-preta, mucunarajada,feijão-de-porco, guandu de porte alto, Crotalaria spectabilis e C. breviflora sob diferentes densidades de semeadura (10, 20, 40, 80 e 160 sementes viáveis m-2), e o crescimento de plantas daninhas nessas densidades, em área de tabuleiros costeiros. O experimento foi desenvolvido de maio a agosto de 1996, no Campo Experimental “Antônio Martins”(EMDAGRO/Embrapa-CPATC), em Lagarto, SE. O número de plantas vivas na floração (NPVF) e a matéria seca da parte aérea das leguminosas (MSPA) foram determinados quando, em cada espécie, cerca de 50% das plantas floresceram. Maiores incrementos de MSPA, em resposta ao adensamento populacional, foram observados em C. spectabilis e C. breviflora, seguidas pelo calopogônio, mucuna-preta e mucuna-rajada. Em relação ao feijão-de-porco, a resposta foi negativa, enquanto com o guandu não houve influência. Quanto ao NPVF, as respostas ao adensamento foram lineares e positivas em C. spectabilis, C. breviflora e calopogônio, e quadráticas com ponto de máxima em feijão-de-porco,guandu e mucuna-rajada. Embora nenhum modelo tenha sido ajustado para expressar a relação entre NPVF e adensamento na semeadura de mucuna-preta, a sobrevivência dessa espécie foi reduzida em todas as densidades. Maiores inibições de plantas daninhas ocorreram nas parcelas de mucuna-preta e feijão-de-porco

The Influence Of Sevoflurane And Isoflurane On The Recovery From Cisatracurium-induced Neuromuscular Block [influência Do Sevoflurano E Do Isoflurano Na Recuperação Do Bloqueio Neuromuscular Produzido Pelo Cisatracúrio]

Background and Objectives - The effects of neuromuscular blockers on the neuromuscular junction are potentiated by volatile anesthetics. This study aimed at evaluating the influence of sevoflurane and isoflurane on the recovery of cisatracurium-induced neuromuscular block. Methods - Ninety ASA I and II patients undergoing elective surgeries under general anesthesia were included in this study. Patients were allocated in three groups: Group I (sevoflurane), Group II (isoflurane) and Group III (propofol). All patients were premedicated with intramuscular midazolam (0.1 mg.kg-1) 30 min before surgery. Anesthesia was induced with alfentanil (50 μg.kg-1), propofol (2.5 mg.kg-1) and cisatracurium (0.15 mg.kg-1). Patients were then ventilated under mask with 100% O2 until disappearance of all TOF responses when laryngoscopy and tracheal intubation were performed. Volatile agents for anesthetic maintenance were introduced immediately after tracheal intubation in 2% and 1% concentrations, respectively, for sevoflurane and isoflurane, as well as the propofol continuous infusion (7 to 10 mg.kg-1.h-1) for Group III. All patients received a 50% mixture of O2 and N2O. Neuromuscular function was monitored by adductor pollicis muscle acceleromyography with TOF stimulation at 15-second intervals. Clinical duration of neuromuscular block (T125%) and recovery index (RI=T125.75%) were evaluated. Results - Mean time and standard deviation for clinical duration (T125%) and recovery index (RI=T125.75%) were respectively: Group I (66.2 ± 13.42 min and 23.6 ± 5.02 min), Group II (54.4 ± 6.58 min and 14.9 ± 3.82 min) and Group III (47.2 ± 7.43 min and 16.2 ± 2.93 min). There were significant differences in clinical duration between Groups I and II, I and III and II and III. There was a significant difference in recovery index between Group I and the other groups. Conclusions - The recovery from cisatracurium-induced neuromuscular block was longer during anesthesia with volatile agents as compared to propofol. The most pronounced effect was observed with sevoflurane.525517524Rupp, S.M., Miller, R.D., Gencarelli, P.J., Vecuronium-induced neuromuscular blockade during enflurane, isoflurane, and halothane anesthesia in humans (1984) Anesthesiology, 60, pp. 102-105Vanlinthout, L.E.H., Booij, L.H.D.J., Van Egmond, J., Effect of isoflurane and sevoflurane on the magnitude and time course of neuromuscular block produced by vecuronium, pancuronium and atracurium (1996) Br J Anaesth, 76, pp. 389-395Suzuki, T., Iwasaki, K., Fukano, N., Duration of exposure to sevoflurane effects dose-response relationship of vecuronium (2000) Br J Anaesth, 85, pp. 732-734Xue, F.S., Liao, X., Tong, S.Y., Dose-response and time-course of the effect of rocuronium bromide during sevoflurane anaesthesia (1998) Anaesthesia, 53, pp. 25-30Wulf, H., Ledowski, T., Linstedt, U., Neuromuscular blocking effects of rocuronium during desflurane, isoflurane, and sevoflurane anaesthesia (1998) Can J Anaesth, 45, pp. 526-532Withington, D.E., Donati, F., Bevan, D.R., Potentiation of atracurium neuromuscular blockade by enflurane: Time-course of effect (1991) Anesth Analg, 72, pp. 469-473Ortiz, J.R., Percaz, J.A., Efecto de la técnica anestésica sobre la recuperación del bloqueo neuromuscular por cisatracurio (2001) Rev Esp Anestesiol Reanim, 48, pp. 117-121Braga, A.F.A., Potério, G.M.P., Braga, F.S.S., Influência do sevoflurano e do isoflurano na duração do bloqueio neuromuscular produzido pelo rocurônio (2001) Rev Bras Anestesiol, 51, pp. 2-9Miller, R.D., Way, W.L., Dolan, W.M., Comparative neuromuscular effects of pancuronium, gallamine and succinylcholine during forane and halothane anesthesia in man (1971) Anesthesiology, 35, pp. 509-514Agoston, S., Interactions of volatile anaesthetics with rocuronium bromide in perspective (1994) Eur J Anaesth, 11 (SUPPL. 9), pp. 107-111Yasuda, N., Lockhart, S.H., Eger E.I. II, Comparison of kinetics of sevoflurane and isoflurane in humans (1991) Anesth Analg, 72, pp. 316-324Yasuda, N., Lockhart, S.H., Eger E.I. II, Kinetics of desflurane, isoflurane, and halothane in humans (1991) Anesthesiology, 74, pp. 489-498Wulf, H., Kahl, M., Ledowski, T., Argumentation of the neuromuscular blocking effects of cisatracurium during desflurane, sevoflurane, isoflurane or total i.v. anaesthesia (1998) Br J Anaesth, 80, pp. 308-312Mallampati, S.R., Gatt, S.P., Gugino, L.D., A clinical sign to predict difficult tracheal intubation: A prospective study (1985) Can J Anaesth, 32, pp. 429-434Oris, B., Crul, J.F., Vandermeersch, E., Muscle paralysis by rocuronium during halothane, enflurane, isoflurane, and total intravenous anesthesia (1993) Anesth Analg, 77, pp. 570-573Shanks, C.A., Fragen, R.J., Ling, D., Continuous intravenous infusion balanced, enflurane, or isoflurane anesthesia (1993) Anesthesiology, 78, pp. 649-651Hemmerling, T.M., Shuettler, J., Schwilden, H., Desflurane reduces the effective therapeutic infusion rate (ETI) of cisatracurium more than isoflurane, sevoflurane, or propofol (2001) Can J Anaesth, 48, pp. 532-537Pollard, B.J., Interactions involving relaxants (1994) Applied Neuromuscular Pharmacology, pp. 202-228. , Pollard BJ, Oxford, Oxford University PressVitez, T.S., Miller, R.D., Eger E.I. II, Comparison in vitro of isoflurane and halothane potentiation of d-tubocurarine and succinylcholine neuromuscular blockades (1974) Anesthesiology, 41, pp. 53-56Waud, B.E., Waud, D.R., The effects of diethyl ether, enflurane and isoflurane at the neuromuscular junction (1975) Anesthesiology, 42, pp. 275-280Waud, B.E., Decrease in dose requirements of d-tubocurarine by volatile anesthetics (1979) Anesthesiology, 51, pp. 298-302Brett, R.S., Dilger, J.P., Yland, K.F., Isoflurane causes "flickering" of the acetylcholine receptor channel: Observations using the patch clamp (1988) Anesthesiology, 69, pp. 161-170Lowry, D.W., Mirakhur, R.K., Carroll, M.T., Potency and time course of mivacurium block during sevoflurane, isoflurane and intravenous anesthesia (1999) Can J Anaesth, 46, pp. 29-33Driessen, J.J., Crul, J.F., Jansen, R., Isoflurane and neuromuscular blocking drugs (1986) Anaesth Int Care, 182, pp. 76-82Cannon, J.F., Fahey, M.R., Castagnoli, K.P., Continuous infusion of vecuronium: The effect of anesthetic agents (1987) Anesthesiology, 67, pp. 503-506Shanks, C.A., Pharmacokinetics of the nondepolarizing neuromuscular relaxants applied to the calculation of bolus and infusion dosage regimens (1986) Anesthesiology, 64, pp. 72-86Hunter, J.M., New neuromuscular blocking drugs (1995) N England J Med, 332, pp. 1691-1699Fisher, D.M., Rosen, J.I., A pharmacokinetic explanation for increasing recovery time following larger or repeated doses of nondepolarizing muscle relaxants (1986) Anesthesiology, 65, pp. 286-291Ginsberg, B., Glass, P.S., Quill, T., Onset and duration of neuromuscular blockade following high-dose vecuronium administration (1989) Anesthesiology, 71, pp. 201-205Bock, M., Klippel, K., Nitsche, B., Rocuronium potency and recovery characteristics during steady-state desflurane, sevoflurane, isoflurane or propofol anaesthesia (2000) Br J Anaesth, 84, pp. 43-47Belmont, M.R., Lien, C.A., Quessy, S., The clinical neuromuscular pharmacology of 51W89 in patients receiving nitrous oxide/opioid/barbiturate anesthesia (1995) Anesthesiology, 82, pp. 1139-1145Lepage, J.Y., Malinovsky, J.M., Malinge, M., Pharmacodynamic dose response and safety study of cisatracurium (51W89) in adult surgical patients during N2O-O2-opioid anesthesia (1996) Anesth Analg, 83, pp. 823-829Carpenter, R.L., Eger E.I. II, Johnson, B.H., Pharmacokinetics of inhaled anesthetics in humans: Measurements during and after the simultaneous administration of enflurane, isoflurane, methoxyflurane and nitrous oxide (1986) Anesth Analg, 65, pp. 575-582Wright, P.M.C., Hart, P., Lau, M., The magnitude and time course of vecuronium potentiation by desflurane versus isoflurane (1995) Anesthesiology, 82, pp. 404-411Gill, S.S., Bevan, D.R., Donati, F., Edrophonium antagonism of atracurium during enflurane anaesthesia (1990) Br J Anaesth, 64, pp. 300-305Baurain, M.J., D'Hollander, A.A., Melot, C., Effects of residual concentrations of isoflurane on the reversal of vecuronium-induced neuromuscular blockade (1991) Anesthesiology, 74, pp. 474-47

Priming Versus Bolus. A Comparative Study With Different Cisatracurium Doses [dose Preparatória Versus Injeção Unica. Estudo Comparativo Entre Diferentes Doses De Cisatracúrio]

Background and Objectives - The priming technique is an alternative to shorten nondepolarizing neuromuscular blockers onset time. This study aimed at evaluating maximum neuromuscular block onset, tracheal intubation conditions and cardiocirculatory changes determined by different cisatracurium single or fractional doses. Methods - Participated in this study 80 patients physical status ASA I and II, who were distributed into two groups according to cisatracurium doses: Group I (0.1 mg.kg-1) and Group II (0.2 mg.kg-1). Subgroups were constituted according to the curarization technique employed: subgroups P1 and P2 (priming-dose) - 0.02 mg.kg-1 or 0.04 mg.kg-1 cisatracurium, respectively, followed one minute later, by 0.08 mg.kg-1 or 0.16 mg.kg-1 of the same neuromuscular blocker, respectively; subgroups U1 and U2 - total bolus injection of 0.1 mg.kg-1 or 0.2 mg.kg-1 cisatracurium, respectively. Anesthesia was induced with etomidate, preceded by alfentanil. Train of Four (TOF) stimulation was applied at 12-second intervals to monitor neuromuscular function. Maximum neuromuscular blockade onset time, tracheal intubation conditions and changes in hemodynamic parameters (arterial mean blood pressure and heart rate) were evaluated. Results - Mean times for maximum neuromuscular block onset were: Group / (3.90 ± 0.60 min and 3.88 ± 0.74 min, for subgroups P1 and U1, respectively) and Group II (1.40 ± 0.40 min and 2 ± 0.30 min, for subgroups P2 and U2, respectively) with no significant differences. Comparison between subgroups P1 and P2 and between subgroups U1 and U2, has shown statistically significant differences. Tracheal intubation conditions were acceptable in all patients and there were no cardiovascular changes. Conclusions - Fractional cisatracurium doses have not shortened maximum neuromuscular block onset as compared to bolus injections. They have however produced acceptable tracheal intubation conditions without cardiovascular changes.531916Donati, F., Onset of action of relaxants (1988) Can J Anaesth, 35, pp. S52-S58Foldes, F.F., Nagashima, H., Kornak, P.H., Effect of priming (1993) Anaesth Pharmacol Rev, 1, pp. 49-56Koller, M.E., Husby, P., High-dose vecuronium may be an alternative to suxamethonium for rapid-sequence intubation (1993) Acta Anaesthesiol Scand, 37, pp. 465-468Potério, G.M.B., Braga, A.F.A., Condições de intubação traqueal com pancurônio. O princípio do priming-dose (1989) Rev Bras Anestesiol, 39 (SUPPL. 11), pp. CBA26Braga, A.F.A., Potério, G.M.B., Emprego do pancurônio e alcurônio em doses fracionadas na obtenção de relaxamento muscular para intubação traqueal (1993) Rev Bras Anestesiol, 43 (SUPPL. 17), pp. CBA76Braga, A.A., Potério, G.B., Rousselet, M.S., Atracúrio e intubação traqueal: Priming-dose X injeção única (1994) Rev Bras Anestesiol, 44 (SUPPL. 18), pp. CBA115Mellinghoff, H., Radbruch, L., Diefenbach, C., A comparison of cisatracurium and atracurium onset of neuromuscular block after bolus injection and recovery after subsequent infusion (1996) Anesth Analg, 83, pp. 1072-1075Bluestein, L.S., Stinson L.W., Jr., Lennon, R.L., Evaluation of cisatracurium, a new neuromuscular blocking agent, for tracheal intubation (1996) Can J Anaesth, 43, pp. 925-931Mallampati, S.R., Gatt, S.P., Gugino, L.D., A clinical sign to predict difficult tracheal intubation: A prospective study (1985) Can J Anaesth, 32, pp. 429-434Goldberg, M.E., Larijani, G.E., Azad, S.S., Comparison of tracheal intubating conditions and neuromuscular blocking profiles after intubating doses of mivacurium chloride or succinylcholine in surgical outpatients (1989) Anesth Analg, 69, pp. 93-99Baumgarten, R.K., Carter, C.E., Reynolds, W.J., Priming with nondepolarizing relaxants for rapid tracheal intubation: A double-blind evaluation (1988) Can J Anaesth, 35, pp. 5-11Storella, R.J., Jaffe, J., Mehr, E., In vitro investigation of the priming principle for rapid neuromuscular block (1989) Br J Anaesth, 62, pp. 478-482Foldes, F.F., Rapid tracheal intubation with non-depolarizing neuromuscular blocking drugs: The priming principle (1984) Br J Anaesth, 56, p. 663Schwarz, S., Ilias, W., Lackner, F., Rapid tracheal intubation with vecuronium: The priming principle (1985) Anesthesiology, 62, pp. 388-391Redai, I., Feldman, S.A., Priming studies with rocuronium and vecuronium (1995) Eur J Anaesth, 11, pp. 11-13Paton, W.D.M., Waud, D.R., The margin of safety of neuromuscular transmission (1967) J Physiol, 191, pp. 59-90Waud, B.E., Waud, D.R., The margin of safety of neuromuscular transmission in the muscle of the diaphragm (1972) Anesthesiology, 37, pp. 417-422Mehta, M.P., Choi, W.W., Gergis, S.D., Facilitation of rapid endotracheal intubations with divided doses of non-depolarizing neuromuscular blocking drugs (1985) Anesthesiology, 62, pp. 392-395Hofmockel, R., Bernad, G., Time-course of action and intubating conditions with rocuronium bromide under propofol-alfentanil anaesthesia (1995) Eur J Anaesth, 12, pp. 69-72Feldman, S.A., Rocuronium: Onset times and intubating conditions (1994) Eur J Anaesth, 9, pp. 49-52Musich, J., Walts, L.F., Pulmonary aspiration after a priming dose of vecuronium (1986) Anesthesiology, 64, pp. 517-519Van Aken, H., Mertes, N., Haess, G.M., Pretreatment technique for fast intubation with vecuronium: Intubation conditions and unwanted effects (1986) Acta Anaesthesiol Belg, 37, pp. 199-204Engbaek, J., Viby-Mogensen, J., Pre-curarization: A hazard to the patient? (1984) Acta Anaesthesiol Scand, 28, pp. 61-62Mahajan, R.P., Laverty, J., Lung function after vecuronium pre-treatment in young, healthy patients (1992) Br J Anaesth, 69, pp. 318-319Aziz, L., Jahangir, S.M., Choudhury, S.N.S., The effect of priming with vecuronium and rocuronium on young and elderly patients (1997) Anesth Analg, 85, pp. 663-666Mirakhur, R.K., Lavery, G.G., Gibson, F.M., Intubating conditions after vecuronium and atracurium given in divided doses (the priming technique) (1986) Acta Anaesthesiol Scand, 30, pp. 347-350Glass, P.S., Wilson, W., Mace, J.A., Is the priming principle both effective and safe? (1989) Anesth Analg, 68, pp. 127-134Miller, R.D., The priming principle (1985) Anesthesiology, 62, pp. 381-382Braga, A.F.A., Potério, G.M.B., Braga, F.S.S., Rocurônio: Dose preparatória versus injeção única (1999) Rev Bras Anestesiol, 49, pp. 379-384Harrop-Griffiths, A.W., Grounds, R.M., Moore, M., Intubating conditions following pre-induction priming with alcuronium (1986) Anaesthesia, 41, pp. 282-286Deepika, K., Kenaan, C.A., Bikhazi, G.B., Influence of the priming technique on pharmacodynamics and intubating conditions of cisatracurium (1999) J Clin Anesth, 11, pp. 572-575Stevens, J.B., Walker, S.C., Fontenot, J.P., The clinical neuromuscular pharmacology of cisatracurium versus vecuronium during outpatient anesthesia (1997) Anesth Analg, 85, pp. 1278-1283Hoffmann, W., Schwarz, U., Ruoff, M., Effects of priming technique on onset profile of cisatracurium (1999) Anaesth Reanim, 24, pp. 130-133Puhringer, F.K., Scheller, A., Kleinsasser, A., The effect of different priming doses on the pharmacodynamics of cisatracurium (2000) Anaesthesist, 49, pp. 102-105Naguib, M., Abdulatif, M., Gyasi, H.D., Priming with atracurium: Improving intubating conditions with additional doses of thiopental (1986) Anesth Analg, 65, pp. 1295-1299Muir, A.W., Anderson, K.A., Pow, E., Interaction between rocuronium bromide and some drugs used during anaesthesia (1994) Eur J Anaesth, 11, pp. 93-98Muir, A.W., Houston, J., Marshall, R.J., A comparison of the neuromuscular blocking and autonomic effects of two new short-acting muscle-relaxants with those of succinylcholine in the anesthetized cat and pig (1989) Anesthesiology, 70, pp. 533-540Cason, B., Baker, D.G., Hickey, R.F., Cardiovascular and neuromuscular effects of three steroidal neuromuscular blocking drugs in dogs (Org 9619, Org 9426, Org 9991) (1990) Anesth Analg, 70, pp. 382-388Savarese, J.J., Lien, C.A., Belmont, M.R., The clinical pharmacology of new benzylisoquinoline-diester compounds, with special consideration of cisatracurium and mivacurium (1997) Anaesthesist, 46, pp. 840-849Doenicke, A.W., Czeslick, E., Moss, J., Onset time, endotracheal intubating conditions, and plama histamina after cisatracurium and vecuronium administration (1998) Anesth Analg, 87, pp. 434-438Lepage, J.Y., Malinovsky, J.M., Malinge, M., Pharmacodynamic dose-response and safety study of cisatracurium (51W89) in adult surgical patients during N2O-O2 opioid anesthesia (1996) Anesth Analg, 83, pp. 823-829Bryson, H.M., Faulds, D., Cisatracurium besilate. A review of its pharmacology and clinical potential in anaesthetic practice (1997) Drugs, 53, pp. 848-866Reich, D.L., Mulier, J., Viby-Mogensen, J., Comparison of the cardiovascular effects of cisatracurium and vecuronium in patients with coronary artery disease (1998) Can J Anaesth, 45, pp. 794-79

Disponibilidade de macronutrientes em cultivares de cana-de-açúcar submetidas à competição com Brachiaria brizantha Macronutrients availability in sugarcane varieties grown under increasing densities of Brachiaria brizantha

Objetivou-se com o trabalho verificar os teores foliares dos macronutrientes e o desenvolvimento das cultivares de cana-açúcar 'RB72454', 'RB867515' e 'SP801816' em competição com populações de Brachiaria brizantha. Os tratamentos utilizados foram: 1) cultivar de cana-de-açúcar 'RB72454' e população de B. brizantha de 0, 1, 3, 7, 15, 32, 40, 32, 64, 92, 88 e 112; 2) 'RB867515' e 0, 1, 4, 14, 10, 18, 28, 30, 36, 54, 52 e 72; 3) 'SP801816' e 0, 1, 3, 6, 14, 20, 24, 26, 26, 32, 46 e 56 plantas m-2. Aos 120 dias após a emergência da cultura, foi quantificada a massa seca (MS) da parte aérea da cana-de-açúcar e da B. brizantha. Aos 290 dias após a emergência (DAE), foram coletadas amostras das folhas +3 (terceira folha a partir do ápice das plantas), nas quais foram avaliadas as concentrações de nitrogênio total, fósforo, potássio, magnésio e cálcio. Com o aumento da população de B. brizantha, observou-se redução da MS somente na cultivar 'RB72454'. O aumento na população de B. brizantha reduziu a concentração de fósforo em todas as cultivares, nitrogênio em 'RB72454' e 'SP801816', potássio e magnésio para 'RB72454'. Nas populações mais elevadas de B. brizantha, houve maior competição pelos nutrientes disponíveis no meio, sendo o fósforo o mais limitante. A cultivar 'RB72454' foi a menos competitiva pelos nutrientes no solo. As cultivares apresentaram redução média de 76% na produtividade de colmos na densidade máxima de B. brizantha.<br>This trial aimed to verify foliar levels of macronutrients and development of sugarcane cultivars 'RB72454', 'RB867515' and 'SP801816' under competition with populations of Brachiaria brizantha. The field trial was installed where treatments were: 1) Sugarcane 'RB72454' and B. brizantha population of 0, 1, 3, 7, 15, 32, 40, 32, 64, 92, 88 e 112; 2) 'RB867515' e 0, 1, 4, 14, 10, 18, 28, 30, 36, 54, 52 e 72; 3) 'SP801816' e 0, 1, 3, 6, 14, 20, 24, 26, 26, 32, 46 e 56 plants m-2. At 120 days after crop emergence, the crop and weed shoot dry mass (MS) was analyzed. At 290 days, samples of the 3rd leaf were collected. From these samples, concentration of total nitrogen, phosphorus, potassium, calcium and magnesium where measured. As the competition increased, a reduction in MS was observed only for 'RB72454'. Increases in population B. brizantha caused reduction in leaf phosphorus concentration for all varieties; nitrogen reduction for 'RB72454' and 'SP801816', as well as potassium and magnesium for 'RB72454'. There was higher competition for nutrients as B. brizantha population was increased, being phosphorus the more limiting nutrient for growth under competition. The variety 'RB72454' demonstrated lower competitive ability in relation to the other ones. All varieties presented average reduction of 76% in the yield in maximum density of B. brizantha