Search PubMed⌕ Search

Biomedical subjects

E Keller

Publications and source records attributed to E Keller.

At least 235 records · Page 13Linked to original sources
PubMed1991

[The role and limits of Doppler studies of the uterine arteries].

Döppler study of the uterine arteries investigates the utero-placental vascular bed. It can be used to identify a population at risk of vascular complications, in particular retroplacental hematoma. This type of study is indicated when there is a history of a vascular problem during pregnancy, as well as following the onset during pregnancy of hypertension, pre-eclampsia, delayed intrauterine growth or thrombocytopenia. The measurement technique avoids neighbouring vessels. An abdominal or vaginal approach may be used. The quality of the signal recorded and compliance with practical technical aspects enable long term prediction of the course of the pregnancy and the organisation of appropriate obstetric monitoring.

Evaluation Studies as Topic↗
PubMed1991

[Captopril-renal function scintigraphy in the clarification of arterial hypertension].

Renal artery stenosis (RAS) is a rare cause of hypertension. Radiological tests can disclose the morphological changes, but not their functional effect on renal function and perfusion. Normalization of the blood pressure can be achieved by intervention (operation, percutaneous transluminal renal angiography; PTRA), in cases of prolonged RAS-induced hypertension long-term preservation of the organ function is most important. The purpose of this study was the validation of captopril renography as a screening test for hypertension secondary to RAS prior to PTRA. Captopril renography with 99mTc-MAG 3 has a high sensitivity (94%) and acceptable specificity (88%) for the screening of hypertensive patients. The positive predictive value is 74% and the negative predictive value 98%, compared with the "gold standard" of angiography.

Adolescent↗
PubMed1991

Crescentic glomerulonephritis in Wegener's granulomatosis: morphology, therapy, outcome.

Fourteen patients with Wegener's granulomatosis (WG) and severe renal and extrarenal involvement were studied (serum creatinine on admission 5.8 +/- 3.4 mg/dl). Renal histology showed a necrotizing, crescentic glomerulonephritis in all patients. Despite advanced renal disease on admission cyclophosphamide, steroids (in 13 patients) and plasma exchange (in 9 patients) caused a rapid and sustained improvement of renal function. Four patients required intermittent hemodialysis over a period of one week. After 2 weeks of treatment serum creatinine values below 2 mg/dl (n = 4) indicated a nearly complete recovery of renal function in the long-term follow up (mean serum creatinine achieved after 12 months therapy: 1.1 +/- 0.1 mg/dl (n = 4). Therefore serum creatinine values observed after 2 weeks of therapy, appear to be of prognostic value with regard to renal outcome. No relapse of active WG or progressive renal deterioration was observed during follow-up (22 +/- 13 months) except in one patient with persisting renal impairment. Three patients died (staphylococcus sepsis, intracerebral hemorrhage during hypertensive crisis, pulmonary embolism) during the first two months of therapy. The decline of serum creatinine seemed to be a better indicator of successful therapy than the decrease of anticytoplasmatic antibody (ANCA), erythrocyte sedimentation rate (ESR) and hematuria. On admission ANCA titer neither correlated with serum creatinine, the degree of renal involvement, nor was it of prognostic value. ANCA, serum creatinine and hematuria normalized within 2 to 8 months, whereas ESR and proteinuria remained elevated. Our data indicate a good prognosis of WG even with advanced renal involvement and generalized vasculitis provided aggressive treatment is performed early.

Acute Disease↗
PubMed1990

Successful therapy of meningococcal sepsis in acute disseminated lupus erythematosus with plasmapheresis, immunosuppression, and antibiotics.

A 17-year-old female with a 5-year history of disseminated lupus erythematosus has remained without immunosuppressive therapy for the last 3 years. She was admitted to the hospital for acute abdominal pain, generalized edema, and rapidly developing dyspnea and somnolence. Although all symptoms were consistent with active SLE, septicemia was suspected because of leukocytosis (20,000/microliters), greatly elevated C-reactive protein (45 mg/dl), and normal complement values (C3 0.74 g/l, C4 0.21 g/l). Directly after bacterial blood cultures were prepared, a combined treatment was instituted consisting of plasmapheresis (3 x 2.1 l against fresh frozen plasma), antibiotics, prednisolone, and cyclophosphamide following the last plasmapheresis. Within three days cerebral function returned to normal, edema improved, and CRP fell to 0.5 mg/dl. The blood cultures and pericardial effusion displayed meningococcal colonies.

Adolescent↗
PubMed1990

Velocity prediction in corrective saccades during smooth-pursuit eye movements in monkey.

It has been noted in a variety of studies in both humans and monkeys that saccades made during smooth pursuit eye movements are usually quite accurate. Since saccades are known to be planned on the basis of neuronal information existing at some interval of time before the actual onset of the movement, it is generally accepted that some sort of prediction or use of visual motion velocity is combined with static position error in the execution of these saccades to moving targets. However, statistical treatment of this response in humans has provided evidence for alternative mechanisms, including a strategy of saccading ahead in the direction of target motion without any incorporation of actual speed information about target motion in the response. We reinvestigated this question quantitatively in the monkey on a large data base of saccades. We found evidence that supports the hypothesis that information about target speed per se is used in this species in the production of saccades to moving targets. Multiple linear regression analysis supported the hypothesis that information about the position error and the target velocity that exists at about 100 ms prior to the saccade onset are both required to provide a statistical explanation of saccade size during pursuit eye movements under the conditions of our experiments.

Animals↗
PubMed1990

Effect of chronic variable stress on monoamine receptors: influence of imipramine administration.

Adult male rats were exposed to a series of unpredictable stressors, a paradigm considered to be a model of experimental depression, with or without concurrent administration of imipramine. One day after the last stress event of the chronic regime, binding of cortical beta-adrenoreceptors and the behavioral serotonin (5-HT) syndrome induced by 5-methoxy-N,N,dimethyltryptamine (5-MeODMT) were determined in all the experimental groups. Stressed rats showed an "up-regulation" of cortical beta-adrenergic sites, while similar values to control rats were observed when stressed animals were administered imipramine. Regarding the behavioral 5-HT syndrome, comparable behavioral scores were observed between controls and chronically stressed rats. The combination of chronic exposure to different stressors with imipramine treatment resulted in a significant increase of forepaw treading and Straub tail scores. The probable facilitation of behavioral deficits induced by this scheme of chronic stress and the recovery following concurrent administration of imipramine are discussed.

Animals↗
PubMed1990

A sensitive sandwich enzyme immunoassay for measurement of insulin on microtiter plates.

A sensitive enzyme immunoassay for the measurement of insulin in human sera on microtiter plates was established. The assay is based on the sandwich technique with guinea pig anti-insulin IgG adsorbed at microtiter plate wells, human insulin as standard and the same anti-insulin IgG labeled with horseradish peroxidase. Standards used cover a range from 0 to 1200 pmol/l with a detection limit of 10 pmol/l. Coefficients of variation between 3-7% for intraassay precision and 5-11% for interassay precision were obtained over the concentration range of 80-1000 pmol/l. The correlation of EIA-data with those of a commercially available double antibody radioimmunoassay (r = 0.98) could be expressed by the equation: EIA = 0.97 RIA - 57 pmol/l. Normal fasting serum insulin concentrations in healthy subjects ranged from 11-165 pmol/l. In subjects with potentially diminished basal values concentrations of 10-79 pmol/l were determined. The insulin response in oral glucose tolerance tests of children was discussed, who had a constitutional tall stature or Turner's syndrome, respectively.

Adult↗
PubMed1990

[Prevention of vaginal prolapse in hysterectomy by suspension of the vaginal stump].

For prophylaxis of enterocele and of prolapse of the vagina following hysterectomy, the vaginal stump is fixed in at-risk patients to the sacro-uterine ligaments (known as McCall's suture) or to the sacro-spinal ligament (Amreich-Richter method). We report on the indications and results obtained in 101 sacro-spinal fixations and 211 McCall sutures in vaginal hysterectomy and 118 McCall sutures in abdominal hysterectomy. From 1975 to 1981 sacro-spinal fixation was only occasionally employed in prophylaxis of enterocele. After introduction of the McCall suture in 1982, the use of this method has been steadily increasing and has largely replaced sacrospinal fixation for prophylactic purposes. Nevertheless we are still using this often in cases of total prolapse, since in that situation, the fixation of the vaginal stump to the sacrouterine ligaments (in most cases weakly developed) is insufficient and does not offer enough support. Of a total of 350 McCall sutures performed to date, postrenal anuria occurred twice after kinking of the ureters, a typical complication that requires removal of the McCall suture. In a total of 174 sacro-spinal fixations of the vaginal stump for prophylactic or therapeutic indications, pronounced intraoperative haemorrhage took place in about 5% of the cases, whereas in one case, there was an abscess formation due to an infected haematoma. Technical details on both methods and on avoiding complications are discussed.

Female↗
PubMed1990

Drug therapy in patients undergoing continuous ambulatory peritoneal dialysis. Clinical pharmacokinetic considerations.

Continuous ambulatory peritoneal dialysis (CAPD) is an accepted alternative to haemodialysis in the treatment of end-stage renal failure. The frequently used intraperitoneal administration of antibiotics to treat peritonitis and the possible role of CAPD in the elimination of drugs has stimulated pharmacokinetic research in this field. The 2 principal results derived from these studies are: (1) the elimination capacity of CAPD for drugs given systemically or orally is very low, and (2) drugs administered intraperitoneally rapidly enter the circulation, a significant amount of drug being absorbed from the peritoneal cavity. This pharmacokinetic behavior is easily understood considering some basic and simple pharmacokinetic principles: the higher the volume of distribution of a substance, the lower will be the percentage of drug present in the peritoneal cavity. Thus, a prerequisite for rapid drug elimination by CAPD is a low body volume of distribution of a particular drug. Only in such a case will the drug diffuse into the peritoneal space to a significant extent. For dosing regimens in CAPD patients, the fraction of the dose eliminated by the peritoneal route should be known or estimated. This fraction depends on the relation of the peritoneal clearance to the total body clearance, and on the protein binding of the drug. The low flow rate of the peritoneal effluent (approximately 10 L/day = 7 ml/min) appears to be the most important limiting factor for the low extraction capacity of CAPD. The list of drugs that have been found to be significantly eliminated by CAPD is short: particular mention should be made of the aminoglycosides and some cephalosporins. The data on the peritoneal elimination of vancomycin are inconsistent. Although the intravenous and oral routes have been successfully used for the treatment of peritonitis, the time course of antibiotic concentrations in the peritoneal space appears to favour the peritoneal route of drug administration. During peritonitis, intraperitoneally administered drugs enter the circulation more rapidly and completely, due to the increased permeability of the peritoneal membrane. As long as the dialysate outflow rate and protein binding of the drug are not extensively altered by peritoneal inflammation, however, the extraction capacity of CAPD appears to remain low.

Drug Therapy↗
PubMed1990

[Growth parameters of female athletes during periods of high training load].

Studies of children participating in elite sport training programmes revealed growth disorders. Longitudinal analyses of female gymnasts (whose bone age was distinctly below chronological age) over a period of two years do not suggest a general tendency to growth inhibition. However, the marked variation in the longitudinal data may indicate retardation in individual cases. An evaluation of the growth parameters is of practical importance for the medical care of children participating in intensive training programmes.

Adolescent↗
PubMed1990

[DNA analysis of HLA class II and III genes in sudden infant death (SIDS)].

In 39 cases of SID we studied the polymorphism of HLA-class II genes DRB and DQB and HLA-class III genes C4 (C4A and C4B, genes encoding the fourth complement component) and 21-hydroxylase (21OH-A and 21OH-B, genes encoding the enzyme 21-hydroxylase of the cortisol pathway) by DNA analysis. This study was performed in cooperation with the Institute of Legal Medicine, University of Munich. Compared to healthy controls the percentage of C4B gene deletions, C4B gene duplications (C4B "short") and 21OH-A gene deletions is increased in SIDS. The deviations are statistically not significant. The analysis of the HLA-DR alleles revealed a significant decrease of HLA-DR2 in SIDS compared to controls (p = 0.0016, pc = 0.016). The results of this study indicate a possible role of C4B/21OH-A gene defects as a risk factor in a subgroup of SID cases. This hypothesis has to be confirmed by studying further cases.

Chromosome Aberrations↗
PubMed1990

[The determination of bone age by the Greulich-Pyle and Tanner-Whitehouse methods as a basis for the growth prognosis of tall-stature girls].

Different height predictions of 48 untreated girls with constitutionally tall stature (bone age 10.0-14.0 years) were compared with the final height. The following conclusions were drawn: The height prediction according to Bayley-Pinneau provided the best results. However, by this method the final height of the younger girls is markedly underestimated while that of the older one's is slightly overestimated. Mathematical methods for correction of these errors and for estimation of the growth rates are given in the text.

Adolescent↗