Search PubMed⌕ Search

Biomedical subjects

F Becker

Publications and source records attributed to F Becker.

At least 55 records · Page 3Linked to original sources
PubMed2000

Preoperative intraarterial thrombolysis before surgical revascularization for popliteal artery aneurysm with acute ischemia.

Because a popliteal artery aneurysm (PAA) generates emboli that progressively deteriorate the distal arterial network, they can constitute limb-threatening lesions. In 20 to 40% of cases, discovery of PAA coincides with sudden occlusion and resulting acute ischemia. In 40 to 60% of these patients, surgical revascularization fails and amputation is required. The objective of this prospective study was to assess the value of intraarterial thrombolysis to restore distal runoff before surgical revascularization. Between January 1, 1992 and December 31, 1996, we treated 15 PAA causing acute ischemia in 15 male patients with a mean age of 66.7 years (range, 44 to 87 years). Diagnosis was documented by clinical examination and ultrasound imaging. Intraarterial thrombolysis was performed under arteriographic control through a multiperforated catheter inserted by the anterograde femoral route to the thrombus. After an initial bolus of 100,000 U of urokinase, 600,000 to 1,600,000 U was continuously infused over a period of 6 to 18 hr. Heparin sodium was administered throughout thrombolysis. Surgical revascularization was performed within 1 to 4 days (mean, 2 days) after thrombolysis by exclusion and bypass in 14 cases and percutaneous transluminal angioplasty with stenting in 1 case. The ensuing results showed that, if performed carefully, intraarterial thrombolysis can safely prepare patients presenting with occluded PAA with acute ischemia for surgical revascularization to restore distal runoff. We use this combined technique routinely in our department. Morbidity is low in comparison with the risks of amputation.

Acute Disease↗
PubMed2000

The "galloping" history of intermittent claudication.

Intermittent claudication (IC) due to arterial occlusive disease was first diagnosed by the French veterinary surgeon Jean-François Bouley jeune in a horse drawing a cabriolet in the streets of Paris as early as 1831. The animal was repeatedly exercised and always started to limp with the hind legs at similar work loads. Autopsy revealed partially thrombosed aneurysm of the abdominal aorta and occlusions of both femoral arteries which were correctly identified as the cause of IC. In 1858 the famous neurologist Jean-Martin Charcot working at the Salpêtrière in Paris first discovered the condition in a patient, who was wounded by a bullet during the conquest of Algery and developed iliac artery aneurysm obliterated by a thrombus. He was aware of the first description in veterinary medicine. In Germany IC was also first mentioned in horses (Rademacher, 1838). 13 reports of patients were contributed by the neurologist Heinrich Erb in 1898 and 1904. Some interesting features of the phenomenon of IC like the amount of exercise necessary to provoke it, localization, social relevance, prolongation of the Achilles tendon reflex, decrease of maximal plantar flexion force of the foot and production of "Lewis factor p" are summarized. In human patients arteriosclerosis is the well recognized principal cause of arterial obstructions, in horses, however, the lesions are due to infection by the roundworm Strongylus vulgaris. In the fascinating life cycle the larvae migrate into the intima of small and large arteries and provoke aneurysms and intravascular thrombosis.

Animals↗
PubMed2000

Transrenal fixation of aortic stent-grafts for the treatment of infrarenal aortic aneurysmal disease.

PURPOSE: We evaluated our early experience with the transrenal fixation of aortic stent-grafts to determine the efficacy of this procedure and its effects on renal artery patency and hemodynamics. METHODS: Twenty-eight patients (22 men) had endoluminally placed modular bifurcated stent-grafts with a bare spring structure at the proximal end crossing the origin of both renal arteries; no patient with infrarenal fixation was included for analysis. The mean age of the patients was 75 +/- 7 years (range, 58-86 years); the mean aneurysm size was 5.8 +/- 0.8 cm (range, 4.7-7.2 cm). Eight patients had preoperative or intraoperative angiographic evidence of renal artery atherosclerotic disease, but only four vessels had luminal narrowing of 50% or greater. No complications were noted during stent-graft placement, and all patients have returned for follow-up visits, ranging from 1 to 12 months (mean follow-up, 6 +/- 4 months). Follow-up evaluations included clinical assessment, duplex ultrasound scan of the renal arteries and kidneys, and computed tomographic angiography. RESULTS: No evidence of lobular or sublobular perfusion defects of the renal parenchyma was detected postoperatively. Two patients exhibited postoperative changes in renal artery hemodynamics-one progressing from a 30% diameter reduction to a greater than 60% diameter stenosis at the 12-month follow-up visit and one with a normal renal artery preoperatively having elevated flow velocities indicative of a greater than 60% stenosis at the 1-month visit. Of 19 patients with normal preoperative renal function, only one has had persistently elevated serum creatinine levels. CONCLUSION: We conclude from this experience that the transrenal placement of open stents is safe and effectively excludes the aneurysm, potentially expanding the availability of this technique to more patients with a short infrarenal aortic neck. Long-term follow-up is essential to determine the overall efficacy of this technique and to identify potential effects on renal artery hemodynamics or kidney function.

Aged↗
PubMed2000

Feasibility and reliability of ankle/arm blood pressure index in preventive medicine.

Despite its potential usefulness for assessing preclinical atherosclerosis and cardiovascular risk, the ankle/arm blood pressure index (AAI) has not yet been the matter of study evaluating its feasibility and reliability by nonspecialist doctors in a general population. This study was planned for two steps. In step 1, the measurement of AAI, (ratio between Doppler systolic pressure at the ankle for each lower limb and the highest value of Doppler systolic pressure of the two upper limbs), should be performed by 50 general practitioners (GPs), 50 social security center physicians, and 50 occupational health physicians in 3,000 male smokers, 40 to 59 years, without clinical cardiovascular disease. In step 2, AAI measurement, coupled with echography-Doppler of iliofemoral arteries, should be repeated by a specialist in all subjects with decreased AAI (<0.90) and the first two subjects with normal AAI recruited in step 1 by each nonspecialist. The number of physicians and subjects participating in step 1 was lower than planned (80 physicians and 962 subjects) with the greatest defect for GPs (six physicians and 35 subjects) and the prevalence of decreased AAI was low (28 subjects). AAI measurement was repeated in step 2 in only 12 subjects with decreased AAI in step 1 and in 124 subjects with normal AAI in step 1. Five of the six subjects with decreased AAI in step 2 also had decreased AAI in step 1 and 123 of the 130 subjects with normal AAI in step 2 also had normal AAI in step 1. As regards echographic stenosis, decreased AAI had a sensitivity of 44% and a specificity of 98%. AAI seems more feasible for occupational health physicians and social security center physicians and AAI is also reliable for nonspecialists previously trained, but its predictive value as regards echographic stenosis is poor in asymptomatic subjects, which may limit its usefulness for detecting preclinical atherosclerosis.

Adult↗
PubMed2000

[Teaching targets in vascular medicine].

The reference list presented here is a selection of educative objectives performed by the French "Collège des Enseignants de Médecine Vasculaire" for the different levels of the medical initial education course. It was produced through a collective procedure, after selecting the most relevant topics and setting up writing rules based upon docimology, and favoring practical rather than theoretical objectives. The main topics are peripheral obstructive arterial disease, polyatherosclerosis, atherosclerosis risk factors, venous thromboembolic disease, thrombophilia, chronic venous insufficiency, lymphatic insufficiency, leg ulcers, vascular acrosyndromes, cerebrovascular diseases and connective tissue diseases, vascular occupational diseases, vascular adverse effects of drugs, diabetic vascular disease, the vascular consequences of hypertension, vascular malformations and angiodysplasia, inflammatory arterial diseases, and vascular explorations. As a whole they include about 300 objectives for the five teaching levels. We hope that this list will help stimulate production of training courses and documents strongly needed in this field.

Education, Medical↗
PubMed2000

Relationship between different stages of the corpus luteum and the expression of the peroxisome proliferator-activated receptor gamma protein in bovine large lutein cells.

Lutein cells produce progestins that support pregnancy. Steroidogenesis requires coordination of the anabolic and catabolic pathways of lipid metabolism. Peroxisome proliferator-activated receptors (PPAR) are transcription factors that are central in the regulation of lipid metabolism. Hence, they may play a role in regulation of the development and regression of the corpus luteum. The present study investigated the expression of PPAR-gamma, n during different stages of the corpus luteum. Lutein cells were isolated mechanically from non-pregnant and pregnant heifers on days 5, 12 and 20 of the oestrous cycle (n = 3 for each day). PPAR-gamma in single cells was analysed by flow cytometry. PPAR-gamma 1 and PPAR-gamma 2 isoforms were distinguished by immunoblotting. The cell cycle of the lutein cells was measured by the flow cytometric quantification of DNA in single cells, using propidium iodide staining after ethanol fixation and RNAse treatment, and by the detection of the proliferating cell nuclear antigen (PCNA). The response of the cells to PPAR-gamma agonist 15-deoxy-delta 12,14 prostaglandin J2 (15dPGJ2, 200 and 490 nmol l-1) with and without changing the cell cycle by the anti-apoptogenic drug aurintricarboxylic acid (ATA, 10 mumol l-1) was used as an in vitro model to study the relationship between the cell cycle and PPAR-gamma. The concentration of PPAR-gamma per cell from non-pregnant heifers was significantly higher on day 5 (3.40 +/- 0.30 fmol) compared with that on day 12 (1.34 +/- 0.18 fmol, P < 0.05) and day 20 (0.55 +/- 0.2 fmol, P < 0.05). In pregnant heifers, the concentration of PPAR-gamma was significantly (P < 0.01) higher than in non-pregnant heifers. A decrease in the PPAR-gamma 1 isoform relative to PPAR-gamma 2 was observed in cells on day 12 of the oestrous cycle compared with day 5. The cell cycle (S phase portion in cells on days 5, 12 and 20: 16 +/- 4%, 6 +/- 4% and 4 +/- 3%, respectively) and the portion of cells with PCNA correlated with the amount of PPAR-gamma in non-pregnant heifers. ATA promoted the S phase in cells of non-pregnant heifers (day 12) and the endogenous agonist of PPAR-gamma, 15dPGJ2, inhibited the response to ATA in a dose-dependent manner, indicating that PPAR-gamma plays a role in the arrest of the cell cycle in lutein cells to maintain their differentiated state.

Analysis of Variance↗
PubMed2000

[Allen's test. 1929].

Explore the source record for details and available documents.

Arterial Occlusive Diseases↗
PubMed1999

[The significance of A1 and A2 antibodies against beta-casein in type-1 diabetes mellitus].

BACKGROUND AND OBJECTIVE: The hypothesis that cow's milk components may constitute environmental factors in the pathogenesis of insulin-dependent diabetes mellitus (IDDM) is increasingly gaining in importance. This study for the first time determined, in a family study, antibodies against the most common variants of the beta-casein (A1 and A2). PATIENTS AND METHODS: A total of 1,257 sera--from 287 patients with IDDM, 386 siblings, 477 individual parents and 107 healthy controls--were tested by enzyme-linked immunosorbent assay (ELISA) for anti-beta casein A1- and A2-IgG antibodies. RESULTS: Antibodies against casein were present in all four groups, highest titres being found in diabetics. In all four groups there was an inverse correlation between A1 and A2 antibodies and age (p < 0.001). Increased amounts of anti-casein A1 antibodies were found among patients with IDDM and their siblings. On the other hand, the serum samples from parents and control persons contained antibodies against the A2 variant. The preferential binding of sera to the one or other casein variant was in all four groups statistically significant (p < 0.001). CONCLUSION: Because the A1 variant of beta-casein correlates with the onset of IDDM, but can also occur in normal controls, this may confirm the hypothesis of a defective oral immunotolerance to cow's milk antigens in IDDM.

Adolescent↗
PubMed1999

Expression of the 180-kD ribosome receptor induces membrane proliferation and increased secretory activity in yeast.

Expression of the canine 180-kD ribosome receptor (p180) in yeast cells resulted in a marked proliferation of intracellular membranes. The type of membranes observed varied with the expression of specific portions of p180. Rough membranes predominated when the ribosome binding domain of p180 was present, whereas expression constructs lacking this region resulted in smooth membranes. Northern analysis indicated that expression of the NH(2)-terminal 767 amino acids (DeltaCT), which include the ribosome binding domain, upregulated the transcription and translation of genes involved in exocytosis. The membranes that were proliferated were functional as these cells overcame a temperature-sensitive translocation defect. Most significantly, cells that overexpressed DeltaCT and proliferated rough endoplasmic reticulum exhibited severalfold higher levels of secretion of an ectopically expressed secretory protein. We conclude that p180 expression triggers a cascade of events leading to an increase in secretory potential akin to the terminal differentiation of mammalian secretory cells and tissues.

Animals↗
PubMed1999

Reticulocytes and solvents: an epidemiological study.

OBJECTIVES: The aim of the study was to look for a rise in reticulocyte levels in workers exposed to various solvents, in comparison to non exposed control subjects. METHODS: A cohort of exposed workers was selected on the criterion of exposure to solvents, among employees regularly attending the Centre of Occupational Medicine of Molsheim (France) during the second trimester of 1995. Controls were selected over the same period from the voluntary blood donors of the Transfusion Centre of Strasbourg (France). Complete blood counts and flow cytometric reticulocyte counts were determined in all blood samples. RESULTS: Analysis of the haematological parameters displaying significant differences revealed the existence of higher levels of circulating reticulocytes and lymphocytes in workers exposed to solvents than in control subjects. These variations did not appear to depend on the intensity or length of exposure. CONCLUSIONS: This study demonstrates the occurrence of an increase in circulating reticulocytes in relation to occupational exposure to solvents, without as yet providing sufficient information to allow elucidation of the underlying mechanism. An increase in total circulating lymphocytes was observed in the same group of exposed workers. The concomitant rise in absolute values of these two elements of the blood counts is to our knowledge described here for the first time in an epidemiological study.

Adult↗
PubMed1999

'Fou rire prodromique' as the heralding symptom of lenticular infarction, caused by dissection of the internal carotid artery in a 12-year-old boy.

A 12-year-old, right-handed boy experienced a pathological fit of laughter before a sudden right hemiplegia. Magnetic resonance imaging showed a left basal ganglia infarction, induced by a left internal carotid dissection. Arteriography revealed an underlying fibromuscular dysplasia. This case study demonstrates that cerebral artery dissection can occur in children and that a basal ganglia infarction may be preceded by pathological laughter called 'fou rire prodromique'. The clinical and anatomical relationship of this paroxysmal event are discussed.

Carotid Artery Diseases↗
PubMed1999

The Giessen-Bad Oeynhausen family study: improved prediction of type I diabetes in a low incidence population of relatives using combinations of islet autoantibodies in a dual step model.

To determine the value of a combined antibody screening for prediction of type I diabetes in a low incidence cohort, we prospectively studied 882 first-degree relatives (485 parents, 382 siblings and 15 offsprings) for up to 11 years who were not preselected for islet cell antibody (ICA) status. During the observation period, 16 individuals developed diabetes. The first serum sample obtained at study entry was analyzed for ICA and antibodies to insulin (IAA), glutamic acid decarboxylase (GADA) and anti-IA-2ic. A multivariate analysis, according to the Cox proportional hazard model considering the joint effects of all baseline variables, selected the four antibodies and the specific family history as significant risk confounding factors (p < 0.05). Further analysis by Kaplan-Meier Life-table methods confirmed a significantly increasing risk of diabetes with the number of autoantibodies present (p < 0.001). In accordance with the Cox model, relatives with more than one affected family member (a multiplex pedigree) and siblings and offsprings vs. parents were at increased risk of IDDM (p < 0.05). In addition to technical problems, a screening strategy based on initial ICA testing has the potential of missing ICA negative subjects among future cases of type I diabetes (19% were ICA negative in the present study) and we therefore set out to evaluate an alternative approach using a dual step strategy with a combination of GADA and anti-IA-2ic for initial screening followed by retesting of positive individuals for ICA and IAA. The combination of GADA and anti-IA-2ic for primary screening (step 1) proved to be more sensitive, identifying 94% of future cases of type I diabetes compared to 81% using ICA as initial test and this antibody combination identified 93% of those individuals with ICA of 20 JDF or more. Retesting of positive individuals for ICA and IAA (step 2) significantly improved the positive predictive value confering a risk of diabetes for siblings and offsprings with more than 2 antibodies within 5 years of 67% (95%CI: 39-90). We conclude that the prognosis of contracting IDDM in relatives is strongly related to the number of autoantibodies present, but the family history should be additionally considered for individual risk assessment. The proposed screening strategy could overcome the inherent problems of the ICA and IAA assays for large-scale screening. In the present study it allows 5-year risk estimates of up to 67% identifying 94% of future cases of type I diabetes.

Adult↗
PubMed1999

Advances in Navy pharmacy information technology: accessing Micromedex via the Composite Healthcare Computer System and local area networks.

The pharmacy profession has long used technology to more effectively bring health care to the patient. Navy pharmacy has embraced technology advances in its daily operations, from computers to dispensing robots. Evolving from the traditional role of compounding and dispensing specialists, pharmacists are establishing themselves as vital team members in direct patient care: on the ward, in ambulatory clinics, in specialty clinics, and in other specialty patient care programs (e.g., smoking cessation). An important part of the evolution is the timely access to the most up-to-date information available. Micromedex, Inc. (Denver, Colorado), has developed a number of computer CD-ROM-based full-text pharmacy, toxicology, emergency medicine, and patient education products. Micromedex is a recognized leader with regard to total pharmaceutical information availability. This article discusses the implementation of Micromedex products within the established Composite Healthcare Computer System and the subsequent use by and effect on the international Navy pharmacy community.

CD-ROM↗
PubMed1999

[Distal cutaneous necrosis, an unusual etiology: hyperhomocysteinemia].

INTRODUCTION: Homocysteine is a sulfur amino acid occurring in methionine intermediary metabolism. It was recently shown to be a vascular risk factor even without high serum levels. CASE REPORT: A 29-year-old woman had painful plantar nodules and necrosis of the fifth toe on the right foot with cyanosis of the forefoot. The histology examination of a nodule biopsy gave the diagnosis of subcutaneous thrombophlebitis. Vascular explorations disclosed advanced-stage arteriopathy of the leg. The methionine loading test was abnormal and search for the heterozygous form of cystathionine ss was positive. DISCUSSION: Different diagnoses could be possible for cases associating an inflammatory venous disease and stage IV arteritis. Latent hyperhomocysteinemia was diagnosed in this case on the basis of the methionine loading test and identification of the heterozygous form of cystathionine ss. Patients with latent hyperhomocysteinemia have an increased risk of both thrombosis and arteritis. Our case emphasizes the importance of searching for hyperhomocysteinemia in patients with early arterial and/or venous thromboembolism, either as repeated episodes or occurring in an unusual territory.

Adult↗
PubMed1998

Sorption Isotherms of Gases by Polymer Membranes in the Glassy State: An Explanation Based on the Nonequilibrium Thermodynamics.

Sorption isotherms of glassy polymers are concave to the pressure axis, and the absolute sorption levels are almost an order of magnitude higher than that of rubbery polymers on the relatively low-pressure side. There are several models to interpret this behavior, and the dual sorption model is the most widely accepted one among them. In the present work, sorption isotherms were first derived from permeation data with several gases for four polymer membranes which might be representative of the dual sorption model: two of them were in a glassy state (cellulose acetate and polyamide), the third one was a block copolymer which was composed of a glassy polymer and a rubbery polymer at the measuring temperature, and the fourth one was a Nafion membrane which was taken as a model membrane because of its channel structure with adsorption sites of charged groups supported by a rubbery polymer. These results did not necessarily support the dual sorption model. Subsequently, the validity of the underlying assumptions of two other sorption models for glassy polymers, that is, the matrix model and the deformation model, were examined and a new equation for the sorption isotherm with an ordering parameter was derived, which implied that the glassy polymer was in a nonequilibrium state and changed from the glassy to the rubbery state by absorbing the gas. Copyright 1998 Academic Press.

Journal Article↗
PubMed1998

PRT1 of Arabidopsis thaliana encodes a component of the plant N-end rule pathway.

Mutants in the PRT1 gene of Arabidopsis thaliana are impaired in the degradation of a normally short-lived intracellular protein that contains a destabilizing N-terminal residue. Proteins bearing such residues are the substrates of an ubiquitin-dependent proteolytic system called the N-end rule pathway. The chromosomal position of PRT1 was determined, and the PRT1 gene was isolated by map-based cloning. The 45-kDa PRT1 protein contains two RING finger domains and one ZZ domain. No other proteins in databases match these characteristics of PRT1. There is, however, a weak similarity to Rad18p of Saccharomyces cerevisiae. The RING finger domains have been found in a number of other proteins that are involved in ubiquitin conjugation, consistent with the proposed role of PRT1 in the plant N-end rule pathway.

Amino Acid Sequence↗