Persistent fetal circulation: an evolving clinical and radiographic concept of pulmonary hypertension of the newborn

The roentgenographic presentations of 11 newborn infants with hypoxemia secondary to pulmonary vasospasm and subsequent right-to-left shunting of blood through the foramen ovale and/or ductus arteriosus (persistent fetal circulation) are described (P. F. C. Syndrome). One infant had radiographically normal lungs, while ten had pulmonary parenchymal abnormalities including hyaline membrane disease [4], meconium aspiration syndrome [4], or an ill defined pattern of retained lung fluid [2]. The roentgenographic appearance of the lungs, however, was discordant with the severe hypoxemia observed in most. Heart size was variable but some degree of cardiomegaly was commonly present. Tolazoline, a potent vasodilator, was useful diagnostically and may have resulted in increased survival. An expanded clinical and roentgeonographic concept of the PFC syndrome is suggested.     

Effects of glutathione-oxidizing agents on microtubule assembly and microtubule-dependent surface properties of human neutrophils

In human peripheral blood polymorphonuclear leukocytes and lymphocytes, GSH-oxidizing agents promote the movement of surface-bound concanavalin A (Con A) into caps and inhibit the assembly of microtubules (MT) that is normally induced by Con A binding. Con A capping and inhibition of MT assembly occur when GSH levels in cell suspensions are decreased by 30-70%, and return to GSH to control levels is accompanied by the appearance of cytoplasmic MT and by inhibition of the capping response with Con A. Oxidation of GSH markedly stimulates the hexose monophosphate shunt, and regeneration of GSH occurs rapidly. The data indicate that MT cannot be assembled or maintained in the face of decreased GSH levels. Thus, GSH homeostasis becomes critical during physiological events such as phagocytosis which simultaneously induce the assembly of MT and the production of agents like H2O2 that can oxidize GSH.     

Glucose turnover in the post-absorptive rat and the effects of halothane anaesthesia

1. Rates and rate coefficients of glucose utilization and replacement in post-absorptive rats, either conscious or under halothane anaesthesia, were determined in a thermoneutral environment by using [5-3H]- and [U-14C]glucose. Label was not injected into rats under halothane until about 0.5h after anaesthesia was initiated. 2. Comparison with the results for 24h-starved rats in the preceding paper [Heath et al. (1977) Biochem. J. 162, 643-651] showed that insulin concentrations were considerably higher but rate coefficients for glucose utilization were little altered in post-absorptive rats. Sensitivity to insulin was thus considerably increased by a 24h period of starvation in the rat. 3. Fractional recycling of glucose carbon in post-absorptive rats was under one-half of that in starved rats, reflecting the larger contribution of liver glycogenolysis to glucose production in the former. 4. In post-absorptive rats halothane decreased the mean rate of glucose utilization by about 17%. This decrease was associated with an increase in mean plasma insulin concentration, showing that halothane decreased sensitivity to insulin. 5. Recycling was slightly increased by halothane, indicating that the contribution of liver glycogen to the total glucogenic rate was decreased, probably because liver glycogen concentration were about 40% lower throughout the rate determinations in halothane. 6. Comparison of our results with earlier work shows that during and shortly after induction of halothane anaesthesia glucose turnover must have been greatly increased whereas from about 0.5h after induction it was decreased.     

Response of plasma fibronectin to major body burn

The ability of macrophages of phagocytize particulate matter is largely dependent on fibronectin, a nonspecific opsonin found in plasma. Fibronectin depletion, resulting in reticuloendothelial system (RES) depression, occurs following a variety of physical insults. RES depression may contribute to postinjury sequelae such as respiratory distress syndrome and septicemia. Fibronectin concentration was measured in the plasma of sheep with chronic lung lymph fistulas subjected to controlled thermal injury. Fibronectin levels were significantly (p < 0.05) decreased at 4, 24, 48, and 72 hours following burning. Fibronectin concentration decreased in parallel with serum albumin concentration; serum globulin concentrations did not decrease. Fibronectin concentration had an inverse relationship to lung lymph flow, a reflection of pulmonary transvascular fluid filtration rate. The role of fibronectin in the pathogenesis of postinjury respiratory distress syndrome deserves further exploration.     

Postmortem anterograde tracing of intrahypothalamic projections of the human dorsomedial nucleus of the hypothalamus

Together with the paraventricular nucleus (PVN), the dorsomedial nucleus of the hypothalamus (DMH) acts as one of the hypothalamic centers that integrate autonomic and central information. The DMH in the rat brain has extensive intrahypothalamic connections and is implicated in a wide variety of functions. Up until now, no knowledge has been available to indicate that the human DMH might have functions similar to those of the rat DMH. In the present study, intrahypothalamic efferent projections of the human DMH were revealed by a recently developed in vitro postmortem tracing method. It was found that the most densely innervated areas are the PVN, the ventromedial nucleus of the hypothalamus, and the area below the PVN. Other significant terminal fields include the periventricular nucleus, the lateral hypothalamic area, and the medial part of the anteroventral hypothalamic area. Scarce fibers project to the suprachiasmatic nucleus, infundibular nucleus, posterior hypothalamic nucleus, and posterior part of the bed nucleus of the stria terminals. The projections of the ventral and dorsal part of the DMH show some differences. The dorsal part of the DMH has denser projections to the dorsal part of the PVN than to the ventral part of the PVN. In contrast, the ventral part of the DMH has denser projections to the ventral part of the PVN. Labeled fibers in the PVN from ventral and dorsal DMH appear to run near many vasopressin and oxytocin neurons of different sizes, and also near some corticotropin- releasing hormone neurons, suggesting that the DMH neurons may directly affect the functioning of these PVN neurons. In many aspects, the observed projections of the human DMH resemble those of the rat, indicating that the organization of DMH intrahypothalamic projections of human is similar to that of rat. The functional significance of DMH intrahypothalamic connections is discussed.     

Impact of apple procyanidins on sensory perception in model cider (part 1): Polymerisation degree and concentration

The impact of the degree of polymerization and of the concentration of procyanidins in a model solution of French cider was investigated. Four purified fractions of procyanidins at three concentrations were added in a solution containing water, ethanol, fructose and malic acid. The four studied sensory characteristics (bitterness, astringency, sweetness and sourness) were modified according to the concentration of procyanidins. The degree of polymerization (DP) of procyanidins influenced only bitterness and astringency but this impact was not the same for all concentrations. Despite the fact that pH, fructose and malic acid concentrations were the same in all samples, the perception of sweetness and sourness were modified according to the concentration of procyanidins.