Search PubMed⌕ Search

Biomedical subjects

J Beyer

Publications and source records attributed to J Beyer.

At least 577 records · Page 32Linked to original sources
PubMedDate not supplied

Value of tumor localization in patients with insulinoma.

Based on our patient material, preoperative localization of insulinoma was correct with sonography in 13 (61.9%) of 21 patients, with computed tomography in 3 (21.4%) of 14 patients, with computed tomography with bolus injection of contrast medium in 11 (73.3%) of 15 patients, with angiography in 20 (66.6%) of 30 patients, and with percutaneous transhepatic portal vein catheterization with selective measurement of insulin in 10 (76.9%) of 13 patients. Intraoperatively, 40 (95.2%) of 42 insulinomas were palpable and 12 of 16 insulinomas were identified during intraoperative sonography. Although 95.2% of the insulinomas can be palpated, we would support additional diagnostic localization since it may improve the reliability of palpation.

Adenoma, Islet Cell↗
PubMedDate not supplied

Multicentre study for diagnostic evaluation of an assay for simultaneous detection of antibodies to HIV-1, HIV-2 and HIV-1 subtype 0 (HIV-0).

The aim of the study was to evaluate a new ELISA for detection of HIV-1, HIV-2 and HIV-1 subtype 0 (HIV-0) antibodies. The assay format is based on the antigen sandwich principle. To enable specific detection of HIV-0 antibodies, in addition to HIV-1 and HIV-2 antigens HIV-0 antigen is used for coating the solid phase and for the conjugate. The results show that all 12 HIV-0 samples tested were detected with a high degree of reactivity, as were all the 1,144 anti-HIV-1 and 424 anti-HIV-2 positive samples. The capacity of the test to enable early detection of seroconversions is equivalent to that of other sandwich ELISAs. The specificity of the assay was determined to be 99.89/99.94% (initial/after retest) using 58,366 samples, which is superior to the other ELISAs used for comparison. Even with difficult samples (i.e. samples of African origin, samples known to cause false-positive reactivity in different ELISAs, or samples containing potential interference factors) there were very few false-positive reactions. Therefore, the new assay is well suited for screening blood donations as well as for evaluating samples from patients of different geographic origin.

Enzyme-Linked Immunosorbent Assay↗
PubMedDate not supplied

Use of amphotericin B aerosols for the prevention of pulmonary aspergillosis.

Invasive pulmonary Aspergillus infections are increasingly recognized among severely neutropenic and/or immunosuppressed individuals. As the infections are usually acquired through the inhalation of Aspergillus conidia, at present prevention of invasive pulmonary aspergillosis consists mainly of the reduction of environmental exposure to aspergillus conidia. More recently, prophylaxis with amphotericin B aerosols has been investigated. Inhalations with amphotericin B aerosols significantly delayed mortality in an animal model of invasive pulmonary aspergillosis and high pulmonary concentrations of amphotericin B could be achieved. In man, pulmonary deposition of amphotericin B could also be demonstrated using commercially available nebulizers. Inhalations were well tolerated with little systemic absorption of the drug. In order to evaluate the efficacy of aerosol amphotericin B administrations for the prevention of invasive pulmonary aspergillosis, a prospective randomized trial has been initiated.

Aerosols↗
PubMedDate not supplied

Selective bilateral blood sampling from the inferior petrosal sinus in Cushing's disease: effects of corticotropin-releasing factor and thyrotropin-releasing hormone on pituitary secretion.

We sought to enhance the sensitivity of selective bilateral blood sampling to determine adrenocorticotropin (ACTH) and prolactin levels in the inferior petrosal sinus (IPS) by administering two stimulatory agents--corticotropin-releasing factor (CRF) and thyrotropin-releasing hormone (TRH). We then determined the ACTH and prolactin levels in the IPS of 10 patients with Cushing's disease. After peripheral administration of both CRF and TRH, ACTH levels were significantly higher on the tumor side in all patients. The prolactin level was significantly higher on the tumor side when CRF or TRH was used to stimulate pituitary secretion. Postsurgical immunohistochemistry studies revealed production of both ACTH and prolactin in tumor cells, explaining the abnormal secretion pattern of the pituitary adenoma. The use of CRF and TRH may therefore improve the reliability of selective blood sampling and tests from the IPS in those cases of Cushing's disease for which noninvasive methods have otherwise failed to clarify the diagnosis.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

The influence of different generations of computer algorithms on diabetes control.

With all control schedules, the management of diabetes is possible using Skyler's algorithm. In general, those control algorithms which do not allow the individual adaptation to changing conditions lead to overinsulinisation. So-called meal-related algorithms do usually minimise the fluctuations in blood sugar. The introduction of self-adapting algorithms, detecting peripheral insulin resistance, may further improve metabolic diabetes control.

Algorithms↗
PubMedDate not supplied

Comparison of the microvascular response to transcutaneous electrical nerve stimulation and postocclusive ischemia in the diabetic foot.

Neurogenic inflammation, mediated by unmyelinated C-nerve fibers, is part of the acute neurovascular response to injury. Laser doppler flowmetry was used to measure the flare response to transcutaneous electrical nerve stimulation (TENS) and to compare this axon reflex vasodilatation with postischemic hyperemia in the skin of the foot in diabetic and nondiabetic subjects. Twenty-one control subjects and 57 diabetic patients (25 type I; 32 type II; 14 without complications; 14 with neuropathy and without retinopathy; 8 with retinopathy and without neuropathy; 21 with neuropathy and retinopathy) were enrolled in the study. Following TENS, an increase in skin blood flow was found at the dorsum of the foot without any significant difference between the different groups. Compared to the control group, axon reflex vasodilatation was significantly reduced in the group of patients with diabetic neuropathy and in the group of patients with diabetic neuropathy and retinopathy at the pulp of the hallux (61 +/- 15 versus -6 +/- 16; versus 23 +/- 5; p < 0.05, respectively). All investigated groups exhibited a significant increase in skin blood flow after arterial occlusion without any significant difference between the groups. A good association was observed between postocclusive and TENS-induced hyperemia at the dorsum of the foot (r = 0.39; p = 0.0002), but only a weak association was found at the pulp of the hallux (r = 0.24; p = 0.03). TENS-induced hyperemia was associated with a diminished sweat response (p = 0.03), but not with pathological cardiovascular function tests (p = 0.07). Electrical axon reflex vasodilatation is diminished in diabetic patients suffering from peripheral autonomic C-fiber injury, especially in skin rich in thermoregulatory blood flow. The diminished neurovascular response is independent of vascular alterations in diabetes mellitus.

Adult↗
PubMedDate not supplied

Comparison of biosynthetic human insulin and pork insulin during rest, food ingestion, and physical work in insulin-dependent diabetic subjects using a glucose controlled insulin infusion system.

In six insulin-dependent diabetic subjects, we investigated whether differences between biosynthetic human insulin (BHI) and pork insulin are present as measured by an automatic glucose controlled insulin infusion system (GCIIS) (Biostator). The parameters measured were basal insulin requirement and food-dependent insulin requirement, as well as the blood sugar-lowering and insulin-saving effect of standardized physical work. The results show that BHI does not reveal any differences with regard to the basal food-independent and food-dependent insulin requirement compared to pork insulin in insulin-requiring diabetic subjects. Delayed food-dependent initial rise in blood sugar and insulin during physical work, which was observed with BHI, does not show any differences in the integral over 180 min. These investigations confirm the results found in vitro and in animal experiments. At the same time, they indicate discrete differences in the activity spectrum.

Animals↗
PubMedDate not supplied

Treatment with human insulin (recombinant DNA) in diabetic subjects pretreated with pork or beef insulin: first results of a multicenter study.

In two double-blind studies 66 insulin-dependent diabetic subjects pretreated with pork insulin were changed to human insulin (recombinant DNA) or a purified pork insulin preparation (regular and NPH insulin). Sixty-five patients previously pretreated with beef insulin were transferred, in a randomized, double-blind fashion, to human insulin and purified beef insulin of the same preparations (regular and NPH insulin). Patients' metabolic control, as demonstrated by fasting and 1-h postprandial blood glucose, HbA1c, and daily insulin dosage, over 4 mo was unchanged in our four groups compared with the values before changing insulin preparation. No severe hypoglycemic attacks or skin reactions were reported.

Adult↗
PubMedDate not supplied

Incidence of subclinical trigeminal and facial nerve involvement in diabetes mellitus.

We investigated the frequency of subclinical trigeminal and facial nerve involvement in 40 patients with diabetes mellitus and without clinical signs of cranial nerve lesions. 60% of the patients had distal symmetric sensory polyneuropathy which was confirmed by nerve conduction studies. Trigeminal and facial nerve functions were evaluated electrophysiologically using the blink-reflex R1 component (BlinkR-R1), masseter reflex (MassR), the first exteroceptive suppression of the masseter muscle (Mass-ES1), and distal motor latency of the facial nerve (DML VII). Latencies were significantly prolonged for the BlinkR-R1 (p < 0.0001), the Mass-ES1 (p < 0.05), and DML VII (p < 0.005) in diabetics compared with controls. No significant difference was found for the MassR. Prolonged latencies (> mean + 2.5 SD of age-matched controls) were demonstrated for the Mass-ES1 in 12.5%, BlinkR-R1 in 10%, DML VII in 6.2%, and MassR in 5% in individual of patients. Our findings indicate that trigeminal and facial nerve involvement is not infrequent in diabetics, although it is significantly less frequent than limb nerve involvement.

Action Potentials↗