Use of percutaneous silastic central venous catheters in neonates and the management of infectious complications.

A prospective study of 35 patients in the neonatal intensive care unit was conducted to examine the safety and feasibility of percutaneous Silastic central venous catheters for the provision of prolonged parenteral alimentation. Particular attention was directed to the possibility of maintaining these lines through intercurrent episodes of infection. Catheters were placed in 34 infants (97%). At the time of insertion, 21 patients (62%) weighed less than 1000 gm and 13 patients (38%) weighed less than 750 gm. The average duration of catheterization was 32.0 +/- 18.2 (SD) days; 19 patients (56%) had lines in place for more than 30 days. Mechanical difficulties complicated the course of five patients (15%). Four cases of bacteremia were identified; this represents 3.7 infections/1000 days of catheter use. All infections were caused by methicillin-resistant staphylococci. Two patients required catheter removal to clear their infection, but in two of the four bacteremic patients, the infection was cleared and the line was sterilized by the administration of antibiotic therapy through the central catheter. We conclude that Silastic central venous catheters can be used safely to deliver intravenous nutrition to extremely small preterm infants over a prolonged period of time, and in carefully selected patients, successful treatment of complicating infections may be achieved without catheter removal.     

The pitfalls of the dexamethasone suppression test: A biological marker of endogenous depression?

In the past few years there have been numerous publications which have stressed the value of the dexamethasone suppression test (DST) as a diagnostic marker of endogenous depression. Our own studies in 333 psychiatric inpatients and 121 healthy subjects did not reveal a differential diagnostic use for the DST. This result is in good agreement with other results in the literature. Our data demonstrate that intervening variables such as severity of illness, weight loss, sleep disturbances, situational stress, drug and alcohol withdrawal, and the pharmacokinetics of dexamethasone have an important influence on DST results, regardless of the diagnostic classification.     

Fetal lumbar spine: measuring axial growth with US

Ultrasound (US) can be used to visualize vertebral segments, suggesting a quantitative means of studying vertebral column growth in utero and thus a means of detecting developmental abnormalities. US images of the lumbar spine were obtained in 128 clinically normal fetuses between the gestational age of 11 through 41 weeks. A large-aperture, dynamically focused US system capable of regional magnification was used. Average lumbar spacing was calculated from distance between centrums of at least four lumbar bodies. The average distance between lumbar centrums increased nearly linearly throughout the second and third trimesters (r2 = 0.98). Enhanced anatomic display implies new capabilities for recognizing developmental abnormalities antenatally.     

Results of animal experiment study of a new enucleation filling of bio-vitroceramics--Bioverit I and II (bioactive and biocompatible)]

The results with two new enucleation prothesis made of Bioverit are presented. After unilateral enucleation 14 rabbits received bioreactive, 14 rabbits biocompatible and 9 rabbits nylon prostheses. Implantation periods: 1-13 months. The tissue surrounding of the prostheses was studied histologically, the ceramic electron microscopically. Of 28 ceramic prostheses, 26 were adapted very well. Bioverit ist excellently suited as orbital prosthetic material, even half-open implants are possible.     

Does timolol modify retinal hemodynamics in patients with normal pressure glaucoma?]

In 31 patients with normal-pressure glaucoma, retinal blood flow, diameter of the retinal vessels and velocity were measured with 2-point fluorometry and automatic measurement of the diameters before and after administration of 0.5% timolol over 2 weeks. After timolol therapy the tension was significantly decreased (before therapy: 18.26 +/- 2.50; after therapy: 15.61 +/- 2.56 mm Hg, P < or = 0.01). The arterial and venous diameters and blood flow were nearly unchanged, but a slight increase in the arterial and venous velocity was noted. We conclude that timolol does not significantly influence the retinal hemodynamics in patients with normal-pressure glaucoma.     

Change in glycemia in a four-year interval in younger-onset insulin-dependent diabetes.

Hyperglycemia is an important risk factor for the development of retinopathy and nephropathy in people with diabetes mellitus. There are few population-based data on changes in glycemia over time. The purpose of this study was to examine changes in glycemia, as measured by glycosylated hemoglobin in 1980 to 1982 and in 1984 to 1986, in a large population-based study of people who were diagnosed to have diabetes before the age of 30 years and who used insulin (n = 697). Glycosylated hemoglobin was measured by a microcolumn technique at both examinations. There was a significant (P < .001) fall in the mean glycosylated hemoglobin from 10.8 to 10.1% over the 4-year interval of the study. In contrast, there was no change in the glycosylated hemoglobin (6.2%) in a similarly aged nondiabetic comparison group over the same period. The decrease in mean glycosylated hemoglobin over the 4-year period in the diabetic group was associated with several characteristics of diabetes management. These include changes in the insulin regimen (going from intermediate- or long-acting insulin only to combinations with short-acting insulin), an increase in the number of doses of insulin per day, and a higher frequency of self-monitoring of blood glucose level. It was also associated with an increased number of reported insulin reactions. These data suggest that recent changes in treatment and management of diabetes may be related to a significant decrease in glycemia.     

Buoyant density characterization of neoplastic cell populations in patients with chronic B-lymphocytic leukemia

Leukemic cells from a series of patients with chronic B-lymphocytic leukemia (CLL) were analyzed for their buoyant density on discontinuous Percoll gradients. The density profile varied markedly between different patients and also between samples from different body compartments within the same patient. A good correlation was observed between buoyant density and maturation stage of the leukemic clones as judged by Ig-expression and their reactivity with a panel of monoclonal antibodies. Phorbol-ester-induced changes in the leukemic cells were found to be accompanied by a general decrease in their buoyant density. No correlation between density and clinical parameters such as cell counts, clinical stage and survival could be noted. Buoyant density characterization of leukemic B-cell populations is seen as a useful, rapid and simple marker of compartmentalization within the B-lymphocyte maturation spectrum but its clinical relevance remains to be established.