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A artrografia com duplo contraste é uma técnica de diagnóstico, que prevê a injeção de um meio de contraste positivo (MCP) no espaço articular, seguido de um meio de contraste negativo, a fim de evidenciar lesões nas superfícies articulares e demais estruturas que as compõem. Essa técnica é um procedimento eficaz e minimamente invasivo, já consolidado na medicina humana e na espécie eqüina, com resultados melhores que os obtidos com métodos usuais de diagnóstico. Este trabalho teve como objetivo descrever e avaliar a técnica de artrografia com duplo contraste, aplicada à articulação do úmero de cães, a qual não consta na literatura. O trabalho apresenta a comparação dessa técnica em relação à artrografia com MCP, na avaliação da superfície articular da cabeça do úmero, porção intra-articular do tendão do músculo bíceps e cápsula articular dos 11 cães submetidos ao exame. O duplo contraste no interior da articulação foi obtido pela combinação de meio de contraste positivo à base de iodo, recobrindo as superfícies articulares e os limites capsulares, e um meio de contraste negativo (ar ambiente), preenchendo o espaço intra-articular. As informações coletadas por quatro radiologistas permitiram concluir que, na avaliação da superfície articular da cabeça do úmero, a técnica de artrografia com duplo contraste demonstra uma melhor imagem em relação à artrografia com MCP, porém, na avaliação do contorno da porção intra-articular do tendão do músculo bíceps, a artrografia com MCP produziu uma imagem melhor que a primeira.(AU)

The double contrast artrography is a diagnostic method in which positive contrast material (MCP) is injected in the joint space followed by negative contrast in order to outline lesions on the articular surfaces and adjacent structures. This technique is an effective and minimally invasive procedure already consolidated in human medicine as well as in the equine species with better results than the ones achieved by using usual diagnostic methods. In dogs this is not widely applied. The present study aimed to describe and evaluate the double contrast artrography technique applied to the humeral joint of canine species to compare with artrography with MCP in the evaluation of the articular surface of humerus head, intra-articular portion of the biceps muscle tendon, and articular capsule of eleven adult dogs. The double contrast within the joint has been produced by combining a small amount of iodine-based half of positive contrast covering the articular surfaces and capsular limits and a larger amount of a negative contrast filling the intra-articular space. The information collected from four radiologists have allowed to conclude that in the evaluation of the articular surface of the humerus head the double contrast artrography technique determinates a better image than with MCP. In addition, in the evaluation of the outline of the intra-articular portion of the biceps muscle tendon the artrography with MCP produced a better image than with double contrast artrography.(AU)

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OBJETIVO: A nefropatia por contraste é a terceira causa de insuficiência renal aguda em pacientes hospitalizados. O objetivo deste estudo foi avaliar a ação da n-acetilcisteína e do alopurinol na proteção renal em ratos de ambos os sexos que receberam diatrizoato. MATERIAIS E MÉTODOS: Ratos Wistar adultos jovens, uninefrectomizados e submetidos a restrição hídrica, receberam solução salina (grupo 1: machos; grupo 2: fêmeas), diatrizoato (grupo 3: machos; grupo 4: fêmeas), diatrizoato e n-acetilcisteína (grupo 5: machos), diatrizoato e alopurinol (grupo 6: machos) e diatrizoato e n-acetilcisteína + alopurinol (grupo 7: machos). A filtração glomerular foi avaliada pela creatinina. O teste t de Student e o teste do sinal foram utilizados para análises estatísticas. RESULTADOS: Ratos que receberam diatrizoato apresentaram elevação estatisticamente significante da creatinina sérica, quando comparados aos controles, porém não houve diferença entre os sexos. Os animais que receberam alopurinol não mostraram aumento significante da creatinina, enquanto a administração de n-acetilcisteína não impediu a elevação da creatinina. CONCLUSÃO: O alopurinol mostrou-se mais efetivo que a n-acetilcisteína na proteção funcional renal ao dano induzido pelo diatrizoato de sódio. Não houve diferença entre os sexos na intensidade do dano renal pelo diatrizoato de sódio.

OBJECTIVE: Contrast medium-induced nephropathy is the third most frequent cause of iatrogenic acute renal failure involving inpatients. The present study was aimed at evaluating the protective effect of n-acetylcysteine and allopurinol in both male and female rats receiving diatrizoate. MATERIALS AND METHODS: Thirty-five young adult Wistar rats submitted to hydric restriction were divided into groups as follows: groups 1 and 2 (respectively male and female rats) receiving saline solution; groups 3 and 4 (respectively male and female rats) receiving diatrizoate; group 5 (male rats) receiving diatrizoate and n-acetylcysteine; group 6 (male rats) receiving diatrizoate and allopurinol; and group 7 (male rats) receiving diatrizoate and n-acetylcysteine + allopurinol. The glomerular filtration was evaluated by measurement of creatinine clearance. Student's t-test and the test of signal were utilized for statistical analysis. RESULTS: Animal models receiving allopurinol did not present a significant increase in the creatinine levels, while n-acetylcysteine did not prevent the creatinine levels increase. CONCLUSION: Allopurinol has shown to be more effective than n-acetylcysteine in the renal function protection against sodium diatrizoate-induced damages. No difference has been found between male and female groups as regards the intensity of sodium diatrizoate-induced renal damages.

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To determine if radiocontrast impairs vascular relaxation of the renal artery, segments (4-5 mm in length) of canine renal artery were suspended in vitro in organ chambers to measure isometric force (95% O2/5% CO2, at 37 C). Arterial segments with and without endothelium were placed at the optimal point of their length-tension relation and incubated with 10 microM indomethacin to prevent synthesis of endogenous prostanoids. The presence of nonionic radiocontrast (iohexol, Omnipaque 350, 1 ml in 25 ml control solution, 4% (v/v)) did not alter endothelium-dependent relaxation to acetylcholine in rings precontracted with both norepinephrine and prostaglandin F2alpha (N = 6). When the rings were precontracted with prostaglandin F2alpha, the presence of ionic contrast did not inhibit the relaxation of the arteries. However, in canine renal arteries contracted with norepinephrine, the presence of ionic radiocontrast (diatrizoate meglumine and diatrizoate sodium, MD-76, 1 ml in 25 ml control solution, 4% (v/v)) inhibited relaxation in response to acetylcholine, sodium nitroprusside (N = 6 in each group), and isoproterenol (N = 5; P < 0.05). Rings were relaxed less than 50% of norepinephrine contraction. Following removal of the contrast, vascular relaxation in response to the agonists returned to normal. These results indicate that ionic radiocontrast nonspecifically inhibits vasodilation (both cAMP-mediated and cGMP-mediated) of canine renal arteries contracted with norepinephrine. This reversible impairment of vasodilation could inhibit normal renal perfusion and act as a mechanism of renal failure following radiocontrast infusion. In the adopted experimental protocol the isoproterenol-induced relaxation of renal arteries precontracted with norepinephrine was more affected, suggesting a pivotal role of the cAMP system.

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To determine if radiocontrast impairs vascular relaxation of the renal artery, segments (4-5 mm in length) of canine renal artery were suspended in vitro in organ chambers to measure isometric force (95 percent O2/5 percent CO2, at 37ºC). Arterial segments with and without endothelium were placed at the optimal point of their length-tension relation and incubated with 10 æM indomethacin to prevent synthesis of endogenous prostanoids. The presence of nonionic radiocontrast (iohexol, Omnipaque 350, 1 ml in 25 ml control solution, 4 percent (v/v)) did not alter endothelium-dependent relaxation to acetylcholine in rings precontracted with both norepinephrine and prostaglandin F2alpha (N = 6). When the rings were precontracted with prostaglandin F2alpha, the presence of ionic contrast did not inhibit the relaxation of the arteries. However, in canine renal arteries contracted with norepinephrine, the presence of ionic radiocontrast (diatrizoate meglumine and diatrizoate sodium, MD-76, 1 ml in 25 ml control solution, 4 percent (v/v)) inhibited relaxation in response to acetylcholine, sodium nitroprusside (N = 6 in each group), and isoproterenol (N = 5; P < 0.05). Rings were relaxed less than 50 percent of norepinephrine contraction. Following removal of the contrast, vascular relaxation in response to the agonists returned to normal. These results indicate that ionic radiocontrast nonspecifically inhibits vasodilation (both cAMP-mediated and cGMP-mediated) of canine renal arteries contracted with norepinephrine. This reversible impairment of vasodilation could inhibit normal renal perfusion and act as a mechanism of renal failure following radiocontrast infusion. In the adopted experimental protocol the isoproterenol-induced relaxation of renal arteries precontracted with norepinephrine was more affected, suggesting a pivotal role of the cAMP system.

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Polymorphonuclear neutrophils (PMN) have an important role in the host defence response to infection. These cells produce large amounts of reactive oxygen species (O(2).(-), H(2)O(2) and ONOO(-)) with microbicidal activity. PMN are commonly isolated from peripheral blood by sedimentation through a gradient of density (Ficoll-Hypaque gradient and dextran), yielding a highly homogeneous cellular population. However, some cellular activation due to membrane perturbation is also expected. We studied how the production of reactive oxygen species and release of myeloperoxidase (MPO) from blood PMN are affected by the use of the Ficoll-Hypaque density gradient. PMN isolated by spontaneous sedimentation and total blood were used for comparisons. Lucigenin- and luminol-enhanced chemiluminescence was used to estimate the production of reactive oxygen from intact cells and shown to be higher for cells isolated by density gradient both in the absence and presence of added stimuli. The release of MPO, estimated by the chemiluminescence of the luminol/H(2)O(2) reaction in the supernatant of PMN incubated in the absence and presence of stimuli and absence and presence of cytochalasin B, was also higher for PMN isolated by a density gradient. In conclusion, it was shown that the PMN isolation procedure affects reactive oxygen species production and MPO release and in some cases may cause a misinterpretation of results.

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It is well known that the radiocontrast-induced ARF depends on risk factors often associated with compromised renal circulation. Since studies have shown that endothelium-dependent vasodilation is impaired in hypercholesterolemia (HC), we studied the effect of radiocontrast (RC) administration (6 ml/kg body wt, via femoral artery) in salt-depleted rats that were kept on a normal cholesterol (NC) or HC diet (4% cholesterol and 1% cholic acid). Inulin clearance (CIn, ml/min/100 g body wt), renal blood flow (RBF; electromagnetic flowmeter, ml/min/100 g body wt), and fractional excretions of sodium, potassium and water (FENa, FEK and FEH2O, respectively), cholesterol (mg/dl), and albumin (g/dl) were measured 24 hours after radiocontrast administration. The administration of RC to HC rats (RCHC) resulted in lower values of CIn compared with NC rats (RCNC) and control rats: 0.36 +/- 0.085 versus 0.76 +/- 0.13 (RCNC; P < 0.01), versus 0.84 +/- 0.03 (control HC; P < 0.01), versus 0.87 +/- 0.06 (control NC; P < 0.01). Hypercholesterolemia per se did not alter renal function, and control HC versus control NC was not significant. Renal blood flow was significantly lower in the RCHC when compared to RCNC (4.3 +/- 0.3 vs. 6.1 +/- 0.3; P < 0.001) and to control animals (control HC 8.2 +/- 0.3; P < 0.001), and control NC 7.5 +/- 0.33 (P < 0.001). To study the role of nitric oxide (NO), HC rats were treated with an infusion of L-arginine or D-arginine (150 mg via femoral artery) in a 50 mg bolus before RC administration and the remaining dose continuously for a period of one hour. The administration of L-arginine to RCHC rats resulted in significantly higher CIn (0.86 +/- 0.1; P < 0.001) when compared to the untreated rats (RCHC). D-arginine did not show a significant difference in CIn (0.49 +/- 0.08). There was a considerable difference between D-arginine RCHC and L-arginine RCHC (P < 0.05). The RBF fall was prevented by L-arginine in RCHC (8.4 +/- 0.23 vs. 4.3 +/- 0.3; P < 0.001), but it was not prevented by D-arginine (5.1 +/- 0.57; P < 0.001). Our data suggest that hypercholesterolemia aggravates nephrotoxicity, which is attenuated by L-arginine but not by D-arginine administration, suggesting that nitric oxide plays a significant role in this model of acute renal failure.

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Objetivo: Determinar cual de los medios de contraste (MC) iónicos producía con mayor frecuencia y gravedad de reacciones adversas (RA) en la urografía excretora(UE),en el Hospital Roosevelt,Guatemala, desde abril de 1996 a febrero de 1997.Material y Métodos: Se realizó un estudio prospectivo seleccionando a 200 pacientes sometidos a UE, que fueron divididos en cuatro grupos(cada uno con n=50),según el MC yodado, hidrosoluble, iónico y alta osmolaridad administrado por vía intravenosa (IV) en dosis de 80 a 100 ml:1) iodamida,2) ioxitalamato,3), amidotrizoato y 4)diatrizoato. Se incluyeron pacientes mayores de 12 años, ambulatorios u hospitalizados, sin antecedentes de RA a los MC, asma, sensibilización al yodo y sin insuficiencia cardíaca congestiva. Se clasificacon las RA en leves, moderadas y graves, según la Organización Mundial de la Salud. Se estabaleció el puntaje de gravedad(PG):RA leve=2,RA moderada=4 y RA grave=8; el PG total(PGT) y el PG promedio (PGP). La gravedad se dividió en baja, intermedia y alta. Se usó distribución de frecuencias en porcentajes y chi cuadrado con p menor o igual de 0,05(5/100). Resultados: La frecuencia de RA fue de 31/100. Leves el 93/100, las moderadas el 7/100 y no hubo graves. El 38/100 de los pacientes con iodamida tuvo RA.La frecuencia de RA de los MC tuvo un valor de p=0,713.El amidotrizoato tuvo el PGP m s alto (4,4); el ioxitalamato tuvo el PGP mas bajo (3,3). El 54/100 de los pacientes tuvo gravedad baja y el 46/100 tuvo intermedia. Discusión: La frecuencia de RA a los MC iodamida, ioxitalamato, amidotrizoato y diatrizoato en la UE fue alta, mayor que lo reportado y sin diferencias importantes entre ellos.Las RA leves fueron muy frecuentes y las moderadas raras. La ausencia de RA graves indica la seguridad de los MC. No hubo diferencias importantes en la gravedad. El PG valoró con objetividad la gravedad de las RA a los MCiónicos usados en UE

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Transient vagal bradycardia occurring during coronary arteriography (CA) immediately following intracoronary injection of ionic contrast medium is believed to be a component of the von Bezold-Jarisch reflex (BJ). Data obtained from experimental animals using buspirone (BSP) and other 5-HT1A receptor ligands suggest that these serotonergic receptors modulate the excitability of cardiac vagal motoneurones (CVM). This is a preliminary investigation of the possible effects of BSP in altering the bradycardia of patients submitted to CA for diagnostic purposes. Patients were divided into two age- and race-matched groups: control (C:N = 45, age 58.6 +/- 1.6 years, mean arterial blood pressure (MAP) 109 +/- 2.4 mmHg, heart rate (HR) 79 +/- 2.9 bpm) and BSP-treated (B:N = 14, age 58.9 +/- 2.1 years, MAP 111 +/- 4.5 mmHg, HR 76 +/- 3.4 bpm). The prevalent underlying pathology was coronary artery disease. Patients with acute angina, congestive heart failure, symptomatic arrhythmia and patients requiring atropine were excluded. CA was performed by a standard procedure using diatrizoate (MD-76) as contrast agent. The left and then the right coronary ostia were selectively catheterized and 8 ml of contrast medium was injected (over a period of 3 sec). HR was measured from ECG tracings before and after contrast injection into the left (LC) and right (RC) coronary arteries. Peak bradycardia was measured as the longest R-R interval during the first 15 sec after the injection minus the pre-injection R-R value, and reported as delta R-R. Group B patients received BSP tablets 48 and 24 h before the examination (30 mg/day po). There was no statistically significant difference (P > 0.05) in bradycardia between groups (C:LC = -147 +/- 23, RC = -155 +/- 25; B: LC = -143 +/- 44, RC = -234 +/- 56 msec). These results suggest that, in contrast to experimental animals, the central 5-HT1A receptors of humans are not relevant for modulating the excitability of CVM in the BJ reflex. However, since drugs and diseases can affect the responses, further studies are necessary to clarify this issue.

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Transient vagal bradycardia occuring during coronary arteriography (CA) immediately following intracoronary injection of ionic contrast medium is believed to be a component of the von Bezold-Jarisch reflex (BJ). Data obtained from experimental animals using buspirone (BSP) and other 5-HT1A receptor ligands suggest that these serotonergic receptors modulate the excitability of cardiac vagal motoneurones (CVM). This is a preliminary investigation of the possible effects of BSP in altering the bradycardia of patients submitted to CA for diagnostic purpose. Patients were divided into two age-and racematched groups: control (C:N=45, age 58.6 + 1.6 years, mean arterial blood pressure (MAP) 109 + 2.4 mmHg, heart rate (HR) 79 + 2.9 bpm) and BSP-treated (B:N=14, age 58.9 + 2.1 years, MAP 111 + 4.5 mmHg, HR 76 + 3.4 bpm). The prevalent underlying pathology was coronary artery disease. Patients with acute angina, congestive heart failure, symptomatic arrhythmia and patients requiring atropine were excluded. CA was performed by a standard procedure using diatrizoate (MD-76() as contrast agent. The left and then the right coronary ostia were selectively catheterized and 8 ml of contrast medium was injected (over a period of 3 sec). HR was measured from ECG tracing before and after contrast injection into the left (LC) and right (RC) coronary arteries. Peak bradycardia was measured as the longest R-R interval during the first 15 sec after the injection minus the pre-injection R-R value, and reported as deltaR-R. Group B patients received BSP tablets 48 and 24 h before the examination (30 mg/day po). There was no statistically significant difference (P>0.05) in bradycardia between groups (C:LC=-147 + 23,RC=-155+25; B:LC=-143 + 44,RC=-234 + 56 msec). These results suggest that, in contrast to experimental animals, the central 5-HT1A receptors of humans are not relevant for modulating the excitability of CVM in the BJ reflex. However, since drugs and diseases can affect the responses, further studies are necessary to clarify this issue.

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In the present study we describe a non-enzymatic technique for the isolation of rat hepatocytes by perfusion of liver through portal vein. The perfusion media consist of 1 mM sodium perchlorate, 5 mM sodium citrate, 10 mM glucose, 129 mM NaCl and 0.1% bovine-serum albumin at pH 7.4. After purification through diatrizoate gradient, electron microscopical studies revealed that most of purified hepatocytes were well preserved and presented a normal ultrastructure, thus correlating with previous biochemical results. The present method enables the recovery of metabolically and morphologically normal hepatocytes.

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In the present study we describe a non-enzymatic technique for the isolation of rat hepatocytes by perfusion of liver through portal vein. The perfusion media consist of 1 mM sodium percholorate. 5 mM sodium citrate, 10 mM glucose, 129 mM NaCl and 0.1 per cent bovine-serum albumin at pH 7.4. After purification through diatrizoate gradient, electron microscopical studies revealed that most of purified hepatocytes were well preserved and presented a normal ultrastructure, thus correlating with previous biochemical results. The present method enables the recovery of metabolically and morphologically normal hepatocytes. (AU)

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In the present study we describe a non-enzymatic technique for the isolation of rat hepatocytes by perfusion of liver through portal vein. The perfusion media consist of 1 mM sodium percholorate. 5 mM sodium citrate, 10 mM glucose, 129 mM NaCl and 0.1 per cent bovine-serum albumin at pH 7.4. After purification through diatrizoate gradient, electron microscopical studies revealed that most of purified hepatocytes were well preserved and presented a normal ultrastructure, thus correlating with previous biochemical results. The present method enables the recovery of metabolically and morphologically normal hepatocytes.

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Se realizó un estudio retrospectivo de 117 casos de pacientes afectados por sordera súbita, agrupados según la terapia recibida. Grupo A: Comprende 40 casos tratados con esteroides mas vasodilatadores. 57.5 por ciento de los pacientes mejoraron su condición de sordera. Grupo B: 57 casos tratados con corticoides mas vasodilatadores y amidotrizoato. Mostró recuperación en el 70.2 por ciento y sin recuperación 29.8 por ciento. Grupo C: 20 casos tratdos únicamente con amidotrizoato. Hubo recuperación en el 70 por ciento y sin recuperación en el 30 por ciento. En la mayor parte de este grupo el tratamiento se inició después de la tercera semana de comenzado el cuadro clínico

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A case of rhabdomyolysis associated with an iodinated contrast medium (sodium diatrizoate) in a patient with chronic renal failure is presented for the purpose of discussing this association. Clinical manifestations were: diffuse myalgias, proximal muscular weakness and an acute reversible deterioration of the renal function. Muscle biopsy showed the typical pattern found in rhabdomyolysis, that is, cellular necrosis with no inflammation signs and myolytic areas. The temporal association between the rhabdomyolysis and the use of the contrast medium suggests a causal relationship. The present case allows us to postulate that the skeletal muscle injury was secondary to direct toxicity and/or the compromise of muscle blood perfusion by the contrast medium in a susceptible muscle due to previous renal failure. It is suggested that this group of substances should be incorporated to the list of agents capable of causing non traumatic rhabdomyolysis.

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We describe a patient with a longstanding paraplegia who developed spinal myoclonus on 3 different occasions spanning one year, once after an enhanced CT scan and twice after excretory urographies, one of which was also followed by a generalized tonic-clonic seizure. To our knowledge only one case of spinal myoclonus secondary to the administration of intravenous contrast material in a patient with a spinal arteriovenous malformation has yet been reported. Taken together, the findings in these cases suggest that spinal myoclonus following intravenous iodine administration is indicative of an underlying spinal cord lesion.

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Se presenta un caso de rabdomiolisis asociado al uso de medio de contraste iodado (diatrizoato de sodio) en un paciente con insuficiencia renal crónica con el propósito de comunicar esta asociación. Sus manifestaciones clínicas fueron mialgias difusas, debilidad muscular y deterioro agudo y reversible de la función renal. La biopsia mostró anormalidades típicas de rabdomiolisis. Se presume que, en este caso, el daño muscular fue secundario a toxicidad directa y/o compromiso crítico del flujo sanguínio muscular por el medio de contraste iodado en un músculo susceptible a la injuria por efecto de la insuficiencia renal. Los medios de contraste iodados deben ser adicionados a la lista de fármacos capaces de provocar rabdomiolisis no traumática, la cual puede ser una complicación más común que lo apreciado (AU)

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Se presenta un caso de rabdomiolisis asociado al uso de medio de contraste iodado (diatrizoato de sodio) en un paciente con insuficiencia renal crónica con el propósito de comunicar esta asociación. Sus manifestaciones clínicas fueron mialgias difusas, debilidad muscular y deterioro agudo y reversible de la función renal. La biopsia mostró anormalidades típicas de rabdomiolisis. Se presume que, en este caso, el daño muscular fue secundario a toxicidad directa y/o compromiso crítico del flujo sanguínio muscular por el medio de contraste iodado en un músculo susceptible a la injuria por efecto de la insuficiencia renal. Los medios de contraste iodados deben ser adicionados a la lista de fármacos capaces de provocar rabdomiolisis no traumática, la cual puede ser una complicación más común que lo apreciado

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We describe a patient with a longstanding paraplegia who developed spinal myoclonus on 3 different occasions spanning one year, once after an enhanced CT scan and twice after excretory urographies, one of which was also followed by a generalized tonic-clonic seizure. To our knowledge only one case of spinal myoclonus secondary to the administration of intravenous contrast material in a patient with a spinal arteriovenous malformation has yet been reported. Taken together, the findings in these cases suggest that spinal myoclonus following intravenous iodine administration is indicative of an underlying spinal cord lesion.

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Films from 246 angiograms performed for acute trauma were reviewed for artifacts that mimic arterial pathology. The population studied was young (mean age 31.8 years), and preexisting arterial disease was uncommon. Thirty patients (12%) exhibited 35 artifactual abnormalities. Artifacts included stationary wave formation (15 patients), admixture in the leading edge of the contrast column (7 patients) or streaming from the inside aspect of an arterial curve (13 patients), Mach bands (8 patients), and abnormal densities caused by the mishandling of film (1 patient) or discharge of static electricity (1 patient). These artifacts have typical morphologic appearances and locations that allow differentiation from pathological processes that manifest as intraluminal filling defects or arterial wall irregularity.

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