Continuous arteriovenous renal replacement systems for critically ill children

Five different arteriovenous renal replacement systems were used to treat 23 critically ill oliguric or anuric children. Slow continuous ultrafiltration (SCU) was carried out for 8 patient days, continuous arteriovenous haemofiltration (CAVH) for 40, suction-supported CAVH for 56, continuous or intermittent arteriovenous haemodiafiltration (AVHDF) for 3, and continuous arteriovenous haemodialysis (CAVHD) for 24 days. SCU allowed excellent control of fluid overload in 4 patients within 47±17 h. Urea clearances ranged from 5.6±2.1 ml/min per m² (spontaneous CAVH) to 15.3±3.7 ml/min per m² (CAVHD) and enabled good control of azotaemia. Ultrafiltration rates of the different filters ranged from 1.6±0.3 to 11.5±2.4 ml/min per m². The only serious complication was a femoral artery thrombosis in a 1.5-year-old boy. Minor side-effects were local bleeding at the entrance site of the arterial catheter and transient hypotension during suction-supported CAVH. Of 23 patients, 8 died because of progressive multiple organ system failure, a mortality of 35%.     

Effects of simultaneous alcohol and toluene poisoning on the cardiovascular system of rats

A group of rats was fed a control liquid diet while another group was fed a liquid diet containing alcohol up to 36% of the total caloric intake. One-half of both groups was placed in an inhalation chamber supplied with fresh air; the other two half-groups were made to inhale air containing 4000 mg toluene/m³ for 6 hr daily, 5 days a week, for a period of 4 weeks. After exposure the ECG, hematocrit, histological structure of the heart, blood pressure, cardiac output, distribution of the cardiac output to the organs, nutritive blood flow and circulatory resistance of the organs were studied in these groups of animals. The ECG, hematocrit values, and histological and histochemical structure of the heart did not change in any of the groups. Toluene inhalation increased myocardial vascular resistance and reduced cerebral nutritive blood flow. Alcohol ingestion reduced the arterial blood pressure, the cardiac index, and nutritive blood flow to the myocardium, kidney, skin, and carcass, while myocardial and cutaneous vascular resistance as well as the cerebral blood flow fraction increased. It was concluded that the cardiovascular sites of action of toluene and alcohol were not identical.     

Surgical correction of forehead wrinkles,glabellar frown,and ptosis of the eyebrows

Lasting elimination of forehead wrinkles and glabellar frown may be achieved by a partial resectioning of the muscles of the forehead. In those cases in which the eyebrows are also lifted, we use a line of incision which is similar to the blepharoplasty of the upper lids used by Morel-Fatio. We carry out the resectioning of the muscle more extensively than is generally described in the literature. It has hereby been observed that the partial resectioning of the musculus frontalis leads to a smoothing out of the horizontal forehead wrinkles, without a tightening of the skin. The results were always satisfactory both for the patients and the surgeons, and the rate of complication was minimal. A result acceptable to the patient can be achieved only if she has been thoroughly informed in advance.     

Intracerebral hemorrhage related to cerebral amyloid angiopathy and t-PA treatment

Tissue plasminogen activator (t-PA) has been approved as thrombolytic therapy for the treatment of acute myocardial infarction, but this agent can cause serious bleeding complications including intracerebral hemorrhages. Mechanisms underlying the development of these hemorrhages have not been clarified. We report a patient who developed two intracerebral hemorrhages shortly after receiving t-PA for the treatment of an acute myocardial infarction, and who was found to have cerebral amyloid angiopathy at autopsy. Staining of cortical sections with Congo red and an antibody directed against beta amyloid protein (A4 peptide) disclosed specific involvement of most of the subarachnoid and superficial cortical vessels in the region of the two hemorrhages. Based on the findings in this patient and in 6 additional patients reported recently, it is likely that cerebral amyloid angiopathy plays a pathogenic role in some intracerebral hemorrhages associated with the administration of t-PA. The cautious use of t-PA with heparin in patients who are elderly or demented may be advisable.     

Protein stability: electrostatics and compact denatured states.

Globular proteins can be denatured by changing pH and ionic strength. Much recent evidence has led to the surprising conclusion that there are two acid-denatured states: one highly unfolded and the other more compact, sometimes called the "molten globule." Here we describe a molecular theory for electrostatic stability of globular proteins based on the properties of the constituent amino acids: oil/water partition coefficients, pK values of the titratable groups, and their temperature dependences. Predicted denaturation temperatures vs. pH are in good agreement with experiments of other workers on myoglobin. The theory also predicts two populations of denatured species, one open and the other more compact, with densities in the range found experimentally for molten globular states. In addition, it predicts a phase diagram (stability vs. pH, ionic strength) in good agreement with experiments of Goto and Fink [Goto, Y. & Fink, A. L. (1989) Biochemistry 28, 945-952; and Goto, Y. & Fink, A. L. (1990) J. Mol. Biol. 214, 803-805]. The well-known salt destabilization of myoglobin has been generally considered evidence for ion pairing, but the present theory, based on smeared charge repulsion, explains the salt destabilization at low pH without ion pairing. In addition, for myoglobin the theory predicts salt stabilization at high pH, as observed for beta-lactamase by Goto and Fink.