Structural characterization of a metal-based perfusion tracer: copper(II) pyruvaldehyde bis(N4-methylthiosemicarbazone)

Copper(II) pyruvaldehyde bis(N4-methylthiosemicarbazone), Cu(PTSM), has been obtained as a dark red crystalline solid from EtOH-DMSO solvent mixture and structurally characterized by x-ray crystallography. The molecule possesses the expected pseudo-square planar N2S2 metal coordination sphere; however, the copper center also interacts through its axial coordination site with the sulfur atom of an adjacent Cu(PTSM) molecule in the crystal lattice. The structure of this compound is compared with the structures of other metal complexes that have been proposed in the nuclear medicine literature as perfusion tracers.

Persistent pulmonary hypertension of the newborn treated with hyperventilation: clinical features and outcome

Twenty-seven infants with severe persistent pulmonary hypertension of the newborn were seen in 33 months. Asphyxia with or without meconium aspiration was the cause in the majority of cases. Other causes were group B streptococcal sepsis and acute fetal blood loss. The mortality rate was 11%. Twenty-three of the 24 survivors were followed. Their age at follow-up ranged 12-37 months. The mean score for mental development was within the normal range while that for psychomotor development was 1 standard deviation below normal. Seven infants were judged to be at risk of attention deficit disorder. Predictor variables related to these outcomes were cardiotocography, meconium aspiration, first pH, highest PaCO2 after resuscitation and mother's education. All infants except one were perceived as normal by their parents.

Dynamics of melittin in water and membranes as determined by fluorescence anisotropy decay

Fluorescence anisotropy decay measurements were performed on melittin in water and in membranes of dimyristoylphosphatidylcholine. The fluorescence of the single tryptophan residue of melittin and of a pyrene label attached to melittin was detected. In water, the slowest relaxation process in the anisotropy decay occurs with a relaxation time of 1.5 or 5.5 ns in the case of low or high ionic strength and corresponds to rotational diffusion of monomeric or tetrameric melittin. Superimposed on this slow process are fast processes in the subnanosecond range reflecting fluctuations of the fluorophores relative to the polypeptide backbone. In membranes, the fast relaxation processes are not much altered. A slow process with a relaxation time of 35 ns is observed and assigned to orientational fluctuations of the melittin helices in membranes.

Physicians' attitudes to after-hours callers: a five year study in a university based family practice centre

A study of 8179 after-hour calls over a five year period is reported from a single training family practice centre. The analysis of the perceived validity of after-hours calls and the physicians' reactions to these contacts showed important differences with regard to patients' race, sex and age and frequency of calls per patient. Negative attitudes were particularly evident in relation to frequent users of after-hours services, black female patients, psychological problems and calls for prescriptions. Possible explanations for these differences are discussed.

Patent ductus arteriosus and retinopathy of prematurity in infants below 27 weeks gestation

Retrospective study of infants who survived the neonatal period after delivery at 24-26 weeks gestation revealed patency of the ductus arteriosus (PDA) in 44%. The mean birthweight of infants who developed PDA was lower. Retinopathy of prematurity (ROP) was seen in 79% of survivors with 24% having grade III or IV involvement. All but one of the more severe grades of ROP occurred among infants with PDA. Infants with PDA required more prolonged ventilatory support. Perinatal factors did not have a significant role in the development of these complications.

Acetyl benzyl disulfide

S-Benzylthio thioacetate, C9H10OS2, Mr = 198.31, monoclinic, P2(1), a = 5.7112(5), b = 8.1912(5), c = 10.6486(8) A, beta = 92.230(8) degrees, V = 497.8(1) A3, Z = 2, Dm = 1.32(1), Dx = 1.323 Mg m-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.47 mm-1, F(000) = 208, T = 299(1) K, RF = 0.024 for 812 reflections. In this molecule, the S-S [2.024(1) A] and S-C [1.802(3), 1.825(4) A] distances are typical and the C-S-S-C dihedral angle [-80.5(1) degree] lies at the lower end of the range reported for related compounds. The acetyl and disulfide groups are coplanar to within +/- 0.01 A. As a consequence, the molecule exhibits a short [3.078(2) A [intramolecular S...O contact.

Effect of acute hypovolemic hypotension on cerebral metabolism in newborn piglets

To evaluate the temporal changes in cerebral energy metabolism in shock during the perinatal period, we studied cerebral blood flow (CBF) and other metabolic variables in newborn piglets subjected an acute hypovolemic hypotension (HVH). By 30 minutes following HVH, the cardiac output dropped 64%, but the CBF was maintained. Serum glucose rose 110% baseline, resulting in an increase in brain glucose delivery. Cerebral metabolic rate of glucose also increased 246%, while that of oxygen remained unaffected. Further, at 30 minutes of HVH, systemic arterial lactate levels increased 250%, but cerebrospinal fluid (CSF) lactate levels remained in the normal range. By contrast, at 60 minutes following HVH, the CBF dropped 60%, the cerebral metabolic rate for glucose dropped 45%, and that of oxygen 43% of the respective baseline values. A profound systemic lactatemia was noted (500% baseline value), with a concomitant rise in the CSF lactate levels to 190% baseline value. These findings suggest that post-hemorrhagic hypovolemia can be divided into two arbitrary, but distinct phases: 1) An initial phase of relative compensation lasting approximately 30 minutes, during which time the brain utilization of metabolic substrates is well preserved. 2) A later phase of decompensation by 60 minutes of HVH, during which time the CBF as well as brain utilization of metabolic substrates drop significantly. By this time a loss of blood-CSF or brain-CSF barrier for lactate can be seen. The findings of this study may have important implications in the treatment of hemorrhagic shock in the perinatal period.

Geographic variation in the onset of decline of ischemic heart disease mortality in the United States

This report examines geographic variation in the onset of the decline of ischemic heart disease (IHD) mortality in white males aged 35-74 during the period 1968-78. Using a quadratic regression model, State Economic Areas (SEAs) were classified as experiencing onset of the decline in 1968 or earlier, 1969-72, or 1973 or later. In the United States as a whole, approximately one-third of SEAs experienced a late onset of the decline (after 1968). Metropolitan SEAs were in advance of non-metropolitan, and the Northeast and Pacific states showed earlier onset than the South and midsections of the country. The acceleration of the national decline after 1972 appears to be due to declines in areas in which rates had been increasing or in plateau until that time. Evidence about geographic variation in the onset of decline may provide clues about social and environmental factors responsible for the decline.

Antenatal and intrapartum events influencing outcome in very low birth-weight infants

The influence of antenatal and intrapartum events and the route of delivery on Apgar scores and short-term outcome was studied in 359 singleton very low birth-weight infants who were resuscitated adequately at birth and had no lethal congenital anomalies. When stratified according to gestation the occurrence of antepartum haemorrhage, pregnancy-induced hypertension and amnionitis had no influence on the outcome while cord prolapse in infants less than 26 weeks resulted in 100% mortality. Prolonged rupture of membranes significantly improved the chances of their survival. The route of delivery did not influence survival, but greater numbers of babies between 27 and 30 weeks delivered by the breech had lower Apgar scores both at 1 and 5 minutes. Survival was dependent on gestational age and the condition at birth among this group of very low birth-weight infants.

Hypotony and experimental rubeosis iridis in primate eyes. A clinicopathologic study

Rubeosis iridis was produced in cynomolgus monkeys by subjecting their eyes to severe surgically induced hypotony. New vessels on the iris showed characteristic fenestrations of endothelial cell walls as well as mitotic activity.

Effect of application pressure and gestational age on transfontanel pressure in healthy neonates

We developed and evaluated a transducer holder and calibrated, spring-loaded applicator for the Ladd intracranial pressure monitor. The transducer holder/applicator combination allows reproducibility of application pressure and assures coplanarity of the transducer and the skin of the anterior fontanel. Measured transfontanel pressure (TFP) increased with increasing application pressure. Mean TFP was 9.1 +/- (SD) 2.6 cm H2O with an application pressure of about 10 g/cm2 in a group of healthy preterm and term infants at 6 h postnatal age. Birth weight, gestational age and mode of delivery did not affect TFP, allowing use of a single normative value and set of confidence limits in all infants at 6 h of postnatal age.

Parathyroid allotransplantation in the treatment of complicated idiopathic primary hypoparathyroidism

Parathyroid allotransplantation was performed in a 25-year-old woman with idiopathic hypoparathyroidism that had been diagnosed at age 4 years. Long-term medical management of the primary condition with vitamin D and oral calcium supplementation was complicated by multiorgan calcinosis and renal failure. At the age of 21 years she received a successful cadaver renal allograft. Four years later she developed calcinosis cutis with widespread skin necrosis. Medical control of calcium and phosphate metabolism was unsatisfactory and the skin necrosis became progressive and life threatening. A parathyroid allograft that was performed with tissue from a parathyroid adenoma resulted in normalization of the serum calcium and phosphorus levels with arrest and subsequent healing of the skin necrosis. Later failure of the parathyroid allograft was followed by successful retransplantation of normal parathyroid tissue from a cadaver organ donor.

Renal response to frusemide in preterm infants with respiratory distress syndrome during the first three postnatal days

The renal effects of frusemide treatment in infants with respiratory distress syndrome shortly after birth and during the first three postnatal days were evaluated. Eighty five infants were randomly assigned to two groups. Forty two received three doses of intravenous frusemide (1 mg/kg) starting at age, mean (SD) 7.5 (4.1) hours and given at approximately 24 hour intervals. Forty three control infants were treated similarly but were not given frusemide. The groups were comparable in birthweight, gestational age, and Apgar score and in pulmonary status, blood gases, serum electrolytes, and postnatal age. Infants who received frusemide had significantly higher fractional excretion of sodium and chloride at 12 to 24, 24 to 48, and 48 to 72 hours, and higher calcium excretion at 24 to 48 and 48 to 72 hours after entry into the study than control infants. The study group had a significantly higher urine output and greater weight loss than the control group at 48 to 72 hours after entry into the study. There was no significant difference between groups in serum sodium, potassium, and calcium and in fractional excretion of potassium and the glomerular filtration rate. Infants with an Apgar score of more than 3 had higher urine output and had a better diuretic response to frusemide than those with a lower score. The results suggest that perinatal hypoxia may play an important role in renal function and in diuretic response to frusemide shortly after birth and early in the postnatal life of infants with respiratory distress syndrome.

Bovine surfactant (surfactant TA) therapy in immature baboons with hyaline membrane disease

As a prelude to clinical trials with a bovine surfactant (surfactant TA), in human infants with hyaline membrane disease, pulmonary and hemodynamic changes following its instillation in premature baboons were investigated. Baboons, delivered by cesarean section at 141 +/- 3.5 days (mean +/- SD, 77% gestation), were provided with intensive care. At 2 hours of age in one group (n = 10), 100 mg/kg of surfactant TA (reconstituted bovine surfactant, Tokyo Tanabe Co., Tokyo) was instilled into the lungs. Sequential measurements and monitoring of pulmonary and hemodynamic variables were carried out in these ten baboons and in a control group of five baboons for 16 hours, at which time the experiments were electively terminated. At birth, the pulmonary compliance, findings of chest radiographs, ratio of arterial PO2 to alveolar PO2, and respirator variables needed to maintain normal blood gas and acid base status were identical in both groups and indicative of severe hyaline membrane disease. Following surfactant instillation, the treated group demonstrated a rapid increase in PO2 with significantly improved ratio of arterial PO2 to alveolar PO2 (from a mean +/- SD pretreatment value of 0.21 +/- 0.11 to 0.45 +/- 0.11 by 16 hours). Pulmonary compliance improved similarly (from pretreatment value of 0.18 +/- 0.06 mL/cm H2O/kg to 0.27 +/- 0.09 mL/cm H2O/kg). Significant reduction in respirator support variables could be achieved in all treated animals; however, in the control animals, the pulmonary status worsened as evidenced by increasing mean airway pressure and respirator variables to keep normal blood gas and acid base status, thus worsening compliance. At autopsy, pulmonary pressure-volume curves were significantly different with large hysteresis obtained in the surfactant-treated group. Although no deleterious effect on hemodynamics was noted in surfactant TA-treated animals, a large patent ductus arteriosus was demonstrated by aortography. Increased lung blood flow, probably due to a large patent ductus arteriosus flow, was demonstrated by radiolabeled microsphere technique. The physiologic significance and clinical relevance of these findings in premature baboons treated with surfactant TA are discussed.

Ultrasound monitoring of diaphragm activity in bilateral diaphragmatic paralysis

Recovery of diaphragm activity after bilateral diaphragmatic paralysis was monitored in a term infant using a mechanical sector scanner fitted with a 5 MHz transducer. The ratio of diaphragmatic excursion during spontaneous breathing and ventilator assistance was used an objective measure for comparison of diaphragmatic activity during recovery. Ultrasound assessment of diaphragm contraction may be used to study progress in diaphragmatic paralysis.

Kidney and spleen twin grafts in rats: unidirectional graft acceptance in unsuppressed ACI recipients

In previous studies, we have shown that vascularized spleen grafts can facilitate the acceptance of simultaneously implanted hearts, especially if host splenectomy is done 3 days later. The present study shows that the same protocol works not only for hearts but also for kidneys. A total of 59 renal allografts were carried out in various combinations between LEW and ACI rats. The recipients were submitted to bilateral nephrectomy at the time of graft implantation and host splenectomy 3 days later. Graft function was assessed by survival time of the animals. In addition, BUN, creatinine, and hematocrit were measured in selected individuals. The following observations were made: 1) LEW kidneys were rejected at 92 +/- 65 days while ACI kidneys failed at 17 +/- 1.4 days (p less than 0.025). 2) Control animals without simultaneous syngenic functioning spleen implant rejected their LEW kidneys at 30.6 +/- 24.3 days (p less than 0.005). 3) Eleven rats never rejected their LEW kidneys (four single, seven twin grafts). 4) BUN, creatinine, and hematocrit differed significantly in rats with functioning kidneys compared to those in end stage renal failure (p less than 0.0005, p less than 0.0025, and p less than 10(-7) respectively). It is concluded that the presence of the donor spleen can facilitate the acceptance of a simultaneous kidney graft to various degrees, depending on the strain combination.

Assuring quality and confidence in new home care technologies

In summation, a quality assurance program must prepare itself to succeed. The groundwork is often tedious and the orchestration of "hi-tech" programs no easy task. But by spending the time required in the development and educational phases, you will effectively avoid the common pitfalls in implementation of "hi-tech" programs. Patient care will run smoothly from beginning to end. All people involved will receive satisfaction in knowing that no compromise in quality is necessary in the transition from the hospital to the home setting.

Effect of ultrafiltration on peritoneal dialysis drug clearances

To determine the effect of dialysate osmolarity on peritoneal dialysis drug transfer, peritoneal dialysis clearances of theophylline, phenobarbital, and tobramycin were determined in 10 rabbits using dialysate containing 1.5 and 4.25% glucose. Urea and creatinine clearances were also obtained for comparison. Under similar dialysis conditions, the peritoneal clearances of the three drugs remained unchanged for the two types of dialysate. In contrast, the peritoneal clearances of urea and creatinine were significantly higher with the use of 4.25% glucose dialysate (p less than 0.001). Thus, peritoneal dialysis clearances of theophylline, phenobarbital and tobramycin are not significantly affected by hypertonicity-induced ultrafiltration during acute peritoneal dialysis.

The pathophysiology of experimental insulin-deficient diabetes in the monkey. Implications for pancreatic transplantation

In an 11-year study of experimental insulin-deficient diabetes (IDDM) induced in rhesus monkeys by streptozotocin or total pancreatectomy, the authors have found that pathophysiologic changes occur in eye and kidney, which closely resemble the early stages of human insulin deficient diabetes mellitus (IDDM). In addition, morphologic changes of thickening of glomerular capillary basement membrane and expansion of mesangial matrix (by light microscopy) appear within 3 years of onset of hyperglycemia. However, progression to irreversible complications of advanced diabetic nephropathy or proliferative retinopathy, have not occurred. This animal model resembles human disease in that the animals tend to become ketotic unless maintained with exogenous insulin; C-peptide production is low to absent, and large amounts of glycosylated hemoglobin develop within a month of onset. The monkeys differ from humans in the absence of hypertension and hyperlipidemia. The authors suggest that the abnormalities in basement membrane form and function caused by hyperglycemia form the necessary background upon which other factors, such as hypertension and hyperlipidemia, then act to cause irreversible complications. The role of pancreatic transplantation is in prevention of these background changes.