Measuring severity in trauma resuscitation

ISS is the most widely used anatomic trauma severity index. This scale uses clinical judgement. It is therefore a subjective method, the validity of which is somewhat questionable. The aim of this study was to compare the clinical index ISS with a new non-specific score; the "simplified acute physiology score" (SAPS). Five-hundred trauma patients were checked retrospectively. Were excluded small traumas which did not require ICU hospitalization. ISS were all calculated by the same specialist and SAPS was drawn out of the initial blood sample examination. The sensitivity (proportion of true positive) and the specificity (proportion of true negative) were calculated for the two scores at all different cut-off points. "Receiver operating characteristic curves" (ROC) were drawn and their areas were compared by means of the Hanley test. The best Youden index, i.e. the fewest false positives for the most true positives, was also calculated. Mean ISS was 23.3 +/- 9.2. Youden index was 0.1; sensitivity and specificity were respectively 57 and 52% for the cut-off points. Mean SAPS was 8.7 +/- 4.3. Youden index was 0.3 and sensitivity and specificity were respectively 68 and 62%. ROC curve area for SAPS was 0.69 +/- 0.02. ROC curve area for ISS was 0.56 +/- 0.03 (p = 0.0001). In trauma, SAPS seemed to be a better predictor of outcome than ISS.     

A late Neandertal femur from Les Rochers-de-Villeneuve, France

In 2002, a Neandertal partial femoral diaphysis was discovered at Les Rochers-de-Villeneuve (Vienne, France). Radiocarbon dated to approximately 40,700 14C years before present, this specimen is one of the most recent Middle Paleolithic Neandertals. The diaphysis derives from an archeological level indicating alternating human and carnivore (mostly hyena) occupation of the cave, reinforcing the close proximity and probable competition of Middle Paleolithic humans with large carnivores for resources and space. Morphological aspects of the diaphysis and ancient DNA extracted from it indicate that it is aligned with the Neandertals and is distinct from early modern humans. However, its midshaft cortical bone distribution places it between other Middle Paleolithic Neandertals and the Chatelperronian Neandertal from La Roche-à-Pierrot, supporting a pattern of changing mobility patterns among late Middle Paleolithic Neandertals on the eve of modern human dispersals into Europe.     

Leucotoxic Activities of Staphylococcus aureus Strains Isolated from Cows, Ewes, and Goats with Mastitis: Importance of LukM/LukF′-PV Leukotoxin

Among the toxins that Staphylococcus aureus is able to secrete, bi-component toxins named leukotoxins target specifically leukocytes, mainly phagocytic cells. Isolates from cows, goats and ewes with mastitis were selected on the basis of the presence or not of the genes encoding the recently described LukM/LukF′-PV leukotoxin. Of the 128 isolates tested, 126 had moderate to high leukotoxic activity to bovine polymorphonuclear cells (PMN). The supernatants of lukM-positive isolates were much more leukotoxic than the supernatants of lukM-negative isolates: mean leukotoxic titers were 122 versus 20 and 581 versus 26 for isolates of bovine and caprine origin, respectively. Among lukM/lukF′-PV positive isolates, those of caprine and ovine origins were more leukotoxic than were isolates of bovine origin (P < 0.01). The two most abundant proteins in the culture supernatant of a highly toxic isolate were purified and identified as the two components of LukM (LukM and LukF′-PV) on the basis of their molecular mass, N-terminal amino acid sequence, and high synergistic activity. LukM/LukF′-PV induced the flattening of bovine PMN at a concentration as low as 3.6 ng/ml (0.1 nM). A higher concentration (18 ng/ml) was necessary to produce the same effect on caprine or ovine PMN. Affinity-purified antibodies to LukM or to LukF′-PV neutralized the leukotoxic effect of all the culture supernatants. They neutralized with the same efficiency the toxic activity of supernatants from lukM/lukF′-PV positive or negative isolates. These results establish that LukM/LukF′-PV is very active on PMN of ruminants and suggest that this leukotoxin could be the most active leukotoxin produced by mastitis isolates. They prompt further studies to delineate the contribution of LukM/LukF′-PV to the pathogenesis of mastitis in ruminants and the protective effect of antibodies to this leukotoxin.     

Fractional excretion of urea as a diagnostic index in acute kidney injury in intensive care patients

Purpose

Acute kidney injury (AKI) is a dynamic process that evolves from an early reversible condition to an established disease. Value of urine indices in the event of AKI is uncertain in critically ill patients. The aim of this study was to evaluate the performance of fractional excretion of urea (FeU) for differentiating persistent from transient AKI in patients admitted to the intensive care unit.

Methods

This was an observational study. Forty-seven patients with AKI according to the RIFLE classification were included. Transient AKI was defined as AKI resolved within 3 days after inclusion. Persistent AKI was defined as persistent serum creatinine elevation or oliguria.

Results

Fractional excretion of urea was lower in case of transient, 33% (25-39), than persistent AKI, 47% (36-61) (P = .001). Areas under the receiver operating characteristic curve for FeU in case of transient AKI were better than those for other urinary indexes, 0.78 (95% confidence interval, 0.63-0.92). Optimal cutoff point according to the receiver operating characteristic curve was 40%. In patients treated with diuretics, FeU was the only predictive index of transient AKI. Fractional excretion of urea gradually increased from days 1 to 7 in transient AKI, whereas plasma creatinine decreased.

Conclusions

Fractional excretion of urea less than 40% was found to be a sensitive and specific index in differentiating transient from persistent AKI in intensive care unit patients especially if diuretics had been administered.     

Selective loss of noradrenergic phenotypic characters in neuroblasts of the rat embryo.

To define the fate of embryonic neuroblasts in rat gut, which transiently express several noradrenergic traits, we investigated the high-affinity uptake of norepinephrine. At 12.5 days of gestation, these cells exhibited immunoreactivity to tyrosine hydroxylase [tyrosine 3-monoxygenase; L-tyrosine, tetrahydropteridine:oxygen oxidoreductase (3-hydroxylating), EC 1.14.16.2] and endogenous catecholamine fluorescence. However, by 13.5 days these noradrenergic neurotransmitter phenotypic characters essentially disappeared. In contrast, norepinephrine uptake, which was also apparent at 12.5 days, persisted at least through 17.5 days. These observations indicate that norepinephrine uptake develops as an additional noradrenergic characteristic in these cells and persists after the disappearance of other noradrenergic traits. Consequently, neurotransmitter phenotypic characters may be transiently displayed during normal development in vivo.     

Changes in intracranial pressure in severe head injured patients in hemodialysis

Two cases of acute post-traumatic renal failure in severely head injured patients are reported. An increase in intracranial pressure (ICP) was shown up by continuous monitoring during haemodialysis: it was more important during conventional haemodialysis than during continuous arteriovenous haemofiltration. Although this effect is well known experimentally, few cases of continuous ICP pressure monitoring have been reported in head injury patients undergoing haemodialysis. The increase in ICP is explained in the dog as a result of blood-brain differences in urea concentration and osmolality leading to an increase in cerebral spinal fluid volume and cerebral tissue swelling. If dialysis is necessary in these patients, it should be carried out early and progressively, the patient's ICP being monitored continuously.