Effect of hemodialysis on whole blood viscosity.

PURPOSE: The purpose of the present study was to examine the effect of hemodialysis procedures on the hemoconcentration status of end-stage renal disease (ESRD) patients. METHODS: We measured whole blood viscosity (WBV) of 30 ESRD patients using a scanning-capillary-tube viscometer before and after hemodialysis. The blood sample size required for WBV measurements was approximately 3 mL. Pre-dialysis specimens for viscosity measurements were obtained via the fistula needle or Perma catheter prior to initiating hemodialysis, and post-dialysis specimens were drawn from the arterial sample port of the hemodialysis line 3.5 hours after initiation of dialysis treatment. RESULTS: Changes in WBV were measured at high and low shear rates: 80% of patients showed an increased high shear viscosity, whereas 73% of patients demonstrated an increased low shear viscosity. The actual percentage increase in WBV observed after hemodialysis at high and low shear rate ranges varied broadly in the 30 patients. CONCLUSIONS: The observed increase in the WBV of ESRD patients over hemodialysis procedures indicates that a segment of patients experience increased flow resistance, particularly at the microcirculatory level. In addition, for the segment of patients experiencing marked increases in WBV during hemodialysis, the vessel wall at the dialysis fistula is exposed to blood with a higher viscosity than at the beginning of the process. The higher blood viscosity at the dialysis fistula is directly related to increased kinetic force and shear stress on the vessel wall, which may be playing a role in increasing the risk of stenosis.

Morbilidad y mortalidad de recien nacidos con peso de nacimiento inferior a 1.500 gramos. / Morbidity and mortality of newborn infants with birth weight less than 1,500 grams

Se estudian 121 RN con PN inferior a 1.500 g., nacidos en la Maternidad del Salvador el ano 1982. La morbilidad mas frecuente fue la ictericia con un 54,6%, le siguen los problemas metabolicos y el S.D.R. La mortalidad global del grupo fue de 61,2% con una mortalidad del 100% para el grupo con PN inferior a 750 g. La primera causa de muerte fue prematurez extrema, le siguen en frecuencia el SDR y luego la hemorragia intracraneana

Ensayo clinico de un medidor transcutaneo de bilirrubina. / Clinical trial with a transcutaneous bilirrubinometer

Se estudia la confiabilidad clinica de un bilirrubinometro transcutaneo en un grupo de 188 recien macidos de la Maternidad del Hospital Salvador con un total de 357 mediciones, comparandolo con las mediciones de bilirrubina serica efectuadas en un bilirrubinometro estandar. El total de ninos estudiados se divide en 5 grupos distintos de acuerdo a sus caracteristicas clinicas y tratamientos efectuados, encontrandose una correlacion estadisticamente significativa en todos ellos, pero solo en 2 grupos con valores de r elevados (.79 y .91).No se aconseja por ahora su uso clinico rutinario y se comentan otras publicaciones extranjeras que utilizan el mismo instrumento

Ictericia en recien nacidos de madres con colestasia intrahepatica del embarazo. Influencia de la leche materna. / Jaundice in newborn infants from mothers with intrahepatic cholestasis of pregnancy. Influence of maternal milk

Se estudian 30 recien nacidos de madres con colestasia intrahepatica del embarazo y 30 controles. Ambos grupos tienen niveles comparables de bilirrubinemia en los primeros seis dias de vida. Se encontro un numero importante de muestras de leche materna y inhiben la conjugacion de bilirrubina in vitro, pero no hubo relacion con los niveles de bilirrubina serica de los recien nacidos. La capacidad inhibitoria de la leche materna es directamente proporcional al contenido total de acidos grasos libres de las muestras analizadas

Infeccion intrahospitalaria por Klesbsiella pneumoniae en un brote de sepsis en recien nacidos. / Cross infection due to Klebsiella pneumoniae in an outbreak of sepsis in newborn infants

1. Se estudiaron 17 recien nacidos desde el punto de vista clinico y bacteriologico, que presentaban signos clinicos de sepsis entre abril y septiembre de 1978, y cuyo agente aislado en todos los casos fue Klebsiella pneumoniae. 2. El cuadro clinico se inicio en promedio a los 7.5 dias de vida. Cuatro de los recien nacidos tenian antecedentes de rotura prematura de membranas. No hubo relacion entre las infecciones del embarazo y la sepsis del recien nacido. El 53% nacieron por cesarea. 3. El 53% fue pretermino,el 70% conmenos de 2.500 gr y el 47% con scores de Apgar al minuto igual o menor de 5. 4. El cuadro clinico se manifesto en el 47% con hepatomegalia, el 70% con palidez terrosa, el 53% hipoactividad el 41% con deshidratacion e ictericia, el 35% con apnea. 5. Se aislo Klebsiella pneumoniae en personal y ambiente. 6.A todas las cepas se les practico estudio de sensibilidad a los antibioticos, encontrandose 3 grupos claramente definidos. 7. La mortalidad fue de 41%

Measurement of bilirubin-albumin binding. I. Comparative analysis of four methods and four human serum albumin preparations.

Four methods for the measurement of bilirubin-albumin binding have been compared. Three of these, the fluorescent dye binding (Direct Yellow 7), Sephadex G-25 column chromatography, and the 2-(4-hydroxyazobenzene)benzoic acid (HBABA) dye binding methods demonstrate significant correlations of measured binding capacities for bilirubin over a range of bilirubin/albumin molar ratios. All three methods concurred in the demonstration that fresh adult human sera had a higher molar albumin binding capacity for bilirubin than the purified human serum albumin preparations. The fluorescent dye binding and Sephadex column methods agreed most closely in defining presumed deficiency in binding capacity. The HBABA dye binding method was less consistent and appeared to measure non-bilirubin binding sites on albumin in addition to bilirubin binding sites. The fourth method, the saturation index, yielded highly variable results as compared with the other methods because of an inherent excessive risk of laboratory error.

Development of bilirubin transport and metabolism in the newborn rhesus monkey.

Hepatic transport and metabolism of bilirubin have been examined in term, premature, and postmature newborn Macaca mulatta (rhesus) monkeys with and without prior phenobarbital treatment of pregnant mother and neonate. In untreated neonates a biphasic pattern of physiologic unconjugated hyperbilirubinemia has been observed. Phase I was characterized by a rapid increase in serum bilirubin concentration to 4.5 mg/dl by 19 hours and an equally rapid decline to 1.0 mg/dl by 48 hours of age. Phase II was characterized by a stable elevation at 1.0 mg/dl (four times greater than in the adult) from 48 to 96 hourse of age, followed by a decline to normal adult concentrations thereafter. An identical pattern was observed in 29 normal, term human neonates, but the duration of each phase was approximately three times as long as that in the monkey. Phase I hyperbilirubinemia appears to result from a sixfold increase in bilirubin load presented to the liver in the neonatal period, combined with marked deficieny in hepatic bilirubin conjugation, the rate-limiting step during Phase I. Hepatic uptake of bilirubin is not rate limiting during Phase I but may contribute to Phase II hyperbilirubinemia. An increased bilirubin load persists throughout the first 19 days of life in the monkey. Phase I physiologic jaundice in the monkey neonate was completely eliminated by prenatal maternal and neonatal administration of phenobarbital. A threefold enhancement of hepatic conjugation of bilirubin (glucuronyl transferase activity) during Phase I entirely accounted for the prevention of hyperbilirubinemia. The bilirubin load was unaffected by administration of phenobarbital. Whereas in control neonates the bilirubin load slightly exceeded hepatic bilirubin conjugating capacity and resulted in retention of bilirubin, in phenobarbital-treated neonates, hepatic conjugating capacity slightly exceeded that required for the bilirubin load. Administration of phenobarbital failed to alter Phase II hyperbilirubinemia and did not enhance either maximal hepatic uptake or excretion of bilirubin. Hepatic glucuronly transferase activity was increased threefold during Phase II and during the remainder of the neonatal period. Premature birth retarded maturation of hepatic glucuronyl transferase activity. In one phenobarbital-treated premature monkey neonate, there was no apparent response to treatment. Accelerated maturation of bilirubin uptake, conjugation, and excretion of bilirubin was observed in one postmature monkey neonate.

Xylose, glucose, and glucuronic acid conjugation of bilirubin in the newborn rat.

The development and relative contribution of hepatic bilirubin conjugation with glucuronic acid, xylose, and glucose was studied in vitro in newborn rats 1-20 days old. In adult control rats, 75% of the conjugates formed were with glucuronic acid, whereas in 1-day-old newborns, only 50% of the conjugates were with glucuronic acid (P less than 0.02) while xylose and glucose conjugates of bilirubin together were equal to that of glucuronic acid. By day 4, total conjugating capacity increased to adult levels and a mature pattern of distribution. In response to phenobarbital treatment, xylose and glucose conjugation increased 4 days earlier than glucuronide conjugation and maximal induction occurred 8 days sooner for nonglucuronide conjugation than for glucuronide.

The effect of promethazine hydrochloride on bilirubin metabolism in the rat.

The effect of 21 days of promethazine-HC1 administration on hepatic bilirubin metabolism and transport was studied in adult rats. A significant increase in mean cumulative hepatic bilirubin uptake (84.5 +/- 7.6 (SE) mug/100 g/min in controls vs. 110.0 +/- 4.3 in treated rats), mean hepatic glucuronide conjugation (1,330 +/- 86 (SE) mug bilirubin conjugated/g liver/40 min in controls vs. 1.713 +/- 61 in treated rats), and mean maximal hepatic excretion (47.2 +/- 4.9 (SE) mug/100 g/min vs. 63.5 +/- 2.7) was observed in treated animals. Mean total liver weight and total hepatic protein also increased significantly. These observations suggest that promethazine is an inducer of protein and enzyme synthesis in rat liver and is capable of significantly stimulating the three major steps in hepatic disposal of bilirubin.

Various bilirubin conjugates in pregnant and nonpregnant rats with and without phenobarbital treatment.

The relative participation of bilirubin conjugating systems other than uridine diphosphate glucuronic acid-dependent bilirubin glucuronyl transferase in 21-day pregnant (P) and nonpregnant (NP) rats with and without prior phenobarbital (PB) administration was studied. Relative enzyme activities of 74.5%, 17.6%, and 7.9% were observed for glucuronic acid, xylose, and glucose conjugates, respectively, in untreated NP rats. Pregnancy itself did not alter the relative activities. In response to PB administration, P rats increased activity less than NP animals for all three enzymes. The ratios of the three conjugates remained unchanged in both P and NP groups after PB stimulation.

[Mechanisms of catecholamine synthesis disorders in the adrenals of rats subjected to physical fatigue]. / Mekhanizmy narusheniia sinteza katekholaminov v nadpochechnikakh krys pri fizicheskom utomlenii

There was a depression of transformation of noradrenaline, DOPA and thyrosine added in vitro, into catecholamines in the adrenal glands of rats after swimming for a period of 8 hours. This permitted to suppose a depression of the activity of phenylethanolamine-N-methyl-transpherase, DOPA-decarboxylase, and, possibly, of tyrosine hydroxylase under these conditions. After the end of swimming, in the presence of 1-tyrosine, there is at first an activation of noradrenaline synthesis, and then there occurs a gradual normalization (on the 7th day) of adrenaline formation. In rats trained for a period of 2 months the extent of reduction of the catecholamine synthesis in the adrenal glands in response to the 8-hour swimming was much less in comparison with the untrained aniamals.