Search PubMed⌕ Search

Biomedical subjects

E Olsen

Publications and source records attributed to E Olsen.

At least 91 records · Page 5Linked to original sources
PubMed1985

Spontaneous endotoxinemia in premature infants: correlations with oral feeding and bowel dysfunction.

Infants admitted to a tertiary care nursery were tested serially to determine the frequency and epidemiology of spontaneous endotoxinemia, a phenomenon suggested by previous studies. Plasma and stools were tested for endotoxin-like activity (ELA) using a Limulus amoebocyte lysate method and results were correlated with clinical data. We detected ELA in plasma of 28 of 47 infants (60%) tested throughout their hospital stay: only two of 58 separate episodes could be attributed to infection. Endotoxinemia was not consistently associated with classical signs of fever, shock, and jaundice. Prior to oral feeding, little or no ELA was detected in stools and endotoxinemia was ascertained in only six of 45 infants (13%). With feeding, fecal ELA concentrations rose sharply, and endotoxinemia was detected in 56% of remaining infants (p less than 0.001). Bowel disease predisposed to endotoxinemia: 16 of 20 infants (80%) with necrotizing entercolitis or difficult establishment on feeding were affected, compared to five of 17 infants (29%) without such problems (p less than 0.01). Fecal ELA concentrations were not abnormally elevated in those with bowel disease. We conclude that endotoxinemia occurs commonly in immature infants as their fecal flora develops with feeding but the amount of circulating endotoxin required for injury and the patterns this takes require further investigation.

Endotoxins↗
PubMed1985

Clobetasol propionate versus fluocinonide creams in psoriasis and eczema.

A double-blind, parallel comparison was made of the short-term efficacy and safety of three times daily regimens of 0.05% clobetasol propionate cream and 0.05% fluocinonide cream in 114 adolescent and adult patients with psoriasis and 113 with eczema. After 2 weeks of topical applications, patients were assessed according to (1) investigators' overall judgment of clinical response, (2) degree of severity of specific signs and symptoms, and (3) patients' evaluation of improvement. In all three response categories in psoriasis, and in two of three in eczema, clobetasol was statistically significantly superior to fluocinonide (p less than 0.05-p less than 0.001). Healing commenced more rapidly with clobetasol and there was no indication of tachyphylaxis. In contrast, the healing rate with fluocinonide slowed noticeably after the first week, and there was a greater tendency to relapse following fluocinonide treatment. Both regimens were safe: drug-related side effects were generally mild and occurred most commonly with fluocinonide therapy in eczema patients. Overall, drug-related effects occurred in 4% of patients receiving clobetasol and 12% receiving fluocinonide (p less than 0.05). Transient morning plasma cortisol reductions below 5 micrograms/dl occurred in 6% of clobetasol-treated patients, reverting to normal within 1 week of the end of treatment.

Administration, Topical↗
PubMed1984

In search of mediators of skin vasodilation induced by transcutaneous nerve stimulation: III. Increase in plasma VIP in normal subjects and in Raynaud's disease.

Previous studies have shown that the widespread and sustained cutaneous vasodilation which can be induced by low-frequency transcutaneous nerve stimulation (TNS) in humans is dependent on a central serotonergic pathway leading to peripheral sympatho-inhibition. In addition, in a bioassay study, the release of a peripheral vasodilator was suggested. However, the TNS-induced dilator response was not blocked by antagonists to a series of known endogenous vasodilators. In the present study another candidate, the vasoactive intestinal polypeptide (VIP) was monitored by means of a specific radioimmunoassay. The results showed an increase in plasma VIP from 5.6 pmol X l-1 before TNS to 7.3 pmol X l-1 after TNS (median values for 15 normal volunteers; P less than 0.05 for the 30% increase). Patients with Raynaud's disease displayed lower levels of VIP than the normal group (median 3.7 pmol X l-1 for 20 patients; P less than 0.01 for the difference from normals). TNS-induced rewarming of the extremities in Raynaud patients was paralleled by 35% increase in plasma VIP (median 5.0 pmol X l-1; P less than 0.01 for the TNS-dependent increase). The results suggest that the TNS-induced increase in plasma VIP parallels the increase in skin temperature in the extremities. However, a causal relationship between the increase in plasma VIP and cutaneous vasodilation remains to be determined. Possible origins of the TNS-dependent increase in plasma VIP are discussed.

Electric Stimulation↗
PubMed1984

Bacterial endotoxins in umbilical cord blood of neonates.

We tested umbilical cord blood from 255 infants for evidence of bacterial endotoxins. Using a Limulus lysate gelation technique, endotoxin-like activity (ELA) was detected in 13 (9.1%) of 142 term infants and in 23 (20.3%) of 113 preterm infants (p less than 0.05), in concentrations ranging from 30 to 3,000 pg Escherichia coli equivalent activity per milliliter of plasma. No factors predisposing to endotoxemia could be detected in term pregnancies but among ELA+ premature infants, placental cultures more frequently revealed gram-negative species (p less than 0.05). Cord blood endotoxemia in the concentrations observed was without obvious consequence in mothers and term infants. Our data confirm the existence of natal endotoxemia, a potential mechanism of perinatal injury.

Endotoxins↗
PubMed1984

The effect of chloral hydrate on genioglossus and diaphragmatic activity.

A child presented with obstructive sleep apnea (OSA) and a near-fatal airway obstruction and respiratory arrest shortly after receiving chloral hydrate (CH). We, therefore, hypothesize that CH might selectively depress upper airway maintaining muscles such as the genioglossus and so predispose to airway obstruction. Genioglossus (GG) and diaphragmatic (DIA) integrated electromyograms (I EMGs) were recorded in four cats and four rabbits before and after hypnotic doses of CH ranging from 200-1000 mg/kg. Results were similar in both species. Peak GG I EMG decreased within 10-20 min after CH in seven of eight animals. Average peak GG I EMGs were decreased from 100% before CH to as low as 37.0 +/- 27.2% (SD) after CH (P less than 0.001). Minimum GG I EMGs fell from 47.2 +/- 27.2% of peak values before CH to as low as 16.0 +/- 9.7% after CH (P less than 0.01). Phasic GG I EMGs decreased from 53.8 +/- 25.1% of peak control activity to as low as 20.6 +/- 24.6% after CH (P less than 0.05). By contrast, peak and phasic DIA I EMGs after CH were not significantly different from those before CH administration. We conclude that hypnotic doses of CH may preferentially depress GG activity as compared with DIA activity. Selective depression of airway-maintaining muscular contraction by CH may place susceptible patients at risk for life-threatening airway obstruction and may preclude the use of CH to facilitate sleep for polygraphic evaluations in patients suspected of having OSA.

Animals↗
PubMed1984

Left ventricular mass, volume and biopsy analysis in prediction of ventricular function after surgery for chronic aortic regurgitation.

The serial application of electrocardiography and echocardiography to 67 selected patients undergoing valve replacement for chronic severe aortic regurgitation, documented regression of hypertrophy and chamber size within six to twelve months of surgery in all cases experiencing haemodynamic improvement. Those patients who had persistently increased patterns of myocardial hypertrophy and abnormal end-diastolic dimensions in the presence of normal prosthetic (homograft) function usually had persistent, irreversibly depressed myocardial function postoperatively. Preoperative noninvasive and angiographic characteristics could not predict ventricular function after surgery. Thus we could not precisely define what level of depressed ventricular performance or what degree of dilatation and myocardial hypertrophy constituted an irreversible state from this data. Although operative factors such as myocardial protection during cardiopulmonary bypass may influence postoperative cardiac performance, preoperative histological and histochemical data was useful in delineating irreversible morphological and function changes contributing to a depressed cardiac function, and therefore may be of prognostic importance.

Aortic Valve Insufficiency↗
PubMed1984

A simple method for extended heart-lung preservation by autoperfusion.

A modification of Robicsek's autoperfusing heart-lung preparation preserved normal structure in the canine lung for 8 hrs and in the heart for 12 hrs. Applicable to both heart and heart-lung transplantation, the system would permit a safe extension of preservation time limits.

Animals↗
PubMed1982

Irreversible morphological changes contributing to depressed cardiac function after surgery for chronic aortic regurgitation.

The timing of surgery in chronic aortic regurgitation remains a difficult problem. To identify variables predictive of postoperative haemodynamic improvement, changes in left ventricular mass, volume, morphology, and histochemistry were analysed in 67 patients undergoing surgery for chronic aortic regurgitation. Patients were divided into two groups: those in whom the left ventricular echo diameters returned to normal after operation (51 patients, group A), and those with postoperative dilatation (16 patients, group B). A preoperative biopsy was obtained in all patients; postoperative tissue samples were available in 13 patients (five from group A, eight from group B). Data were correlated with the postoperative clinical, haemodynamic state over a follow-up period of three years. Regression of hypertrophy was usually incomplete. Echocardiographic and angiographic data could not define the type and degree of dysfunction which was irreversible. Massive fibre hypertrophy (mean 34.1 micrometers), moderately or severely increased interstitial fibrous tissue, reduced levels of the myofibrillar and mitochondrial enzymes adenosine triphosphates and succinate dehydrogenase in pre- and post-operative tissue samples correlated with persistent dilation, cardiac failure, and early death (group B). Irreversible morphological and functional changes contributed to a depressed cardiac function after operation. Preoperative ventricular biopsies are thus of prognostic importance in volume overload.

Adolescent↗
PubMed1982

Diagnosis of atrial thrombi by ultrasound.

Left atrial thrombi were shown by two-dimensional echocardiography in three patients with mitral valve disease and neurological symptoms. In two patients the atrial thrombi had probably been the source of a previous cerebrovascular embolus. In the third, two-dimensional echocardiography detected the development of a recent ball-valve thrombus in the left atrial cavity, which caused intermittent obstruction and syncope. Echocardiographic findings were correlated with anatomical and histological data in all three patients. The spatial orientation provided by the multiple imaging planes of two-dimensional echocardiography permitted correct estimates of the size and position of the thrombus, and this mode was superior to the standard M-mode technique for non-invasive imaging of thrombus. Despite limitations of technique and resolution, the information provided by ultrasound can be extremely helpful in the management of patients. Ultrasonic screening (particularly the two-dimensional mode) is to be recommended in patients with neurological symptoms and clinical evidence of cardiac disease or arrhythmia.

Adult↗