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A Bauer

Publications and source records attributed to A Bauer.

At least 109 records · Page 6Linked to original sources
PubMed2000

Description and validation of a novel liquid metal-free device for venous congestion plethysmography.

We present a newly developed electromechanical sensor with automated calibration for strain-gauge plethysmography (filtrass) and compare it to a conventional mercury-in-Silastic strain-gauge plethysmograph (MSG). Fluid filtration capacity (K(f)) and isovolumetric venous pressure (Piv) of the limb were assessed noninvasively with both devices in 29 healthy volunteers. We found significantly higher K(f) and Piv values with MSG [4.6 +/- 2.0 x 10(-3) ml. min(-1). mmHg(-1). 100 ml tissue(-1) (K(f) units; K(f)U) and 21.2 +/- 8.1 mmHg for Pvi], than with filtrass, giving values of 3.1 +/- 0.8 K(f)U and 15.1 +/- 7.1 mmHg. Because K(f) and Piv are profoundly influenced by the calibration, we investigated the quality of the calibration signal and its impact on the obtained values. We could show that the reproducibility of repeated calibrations was higher with filtrass (58% lower mean +/- SD). The data were grouped according to the quality of calibration, and we found no significant difference in K(f) and Piv between filtrass (3.0 +/- 0.7 K(f)U and 15.9 +/- 6.9 mmHg, respectively) and MSG with good calibration signal (3.3 +/- 0. 8 K(f)U and 18.6 +/- 7.1 mmHg, respectively; no significant difference). However, we obtained significantly higher MSG values (5. 6 +/- 2.0 K(f)U and 23.1 +/- 8.4 mmHg, respectively; P < 0.001) in the group with a bad calibration signal. We suggest that the filtrass sensor, which performs an automatic, standardized calibration procedure and shows a linear signal response to stretch, gives highly reproducible and reliable results and thus is more suitable for routine application.

Adult↗
PubMed2000

Risk factors for cerebral palsy in very low-birthweight infants in the 1980s and 1990s.

One-hundred twenty-nine very low-birthweight infants were treated in Newborn and Infant Care Department of Children's Memorial Health Institute between 1985 and 1994; 89 were taken to prospective neurodevelopmental care. The newborns were divided into two groups. Group I had 38 preterm infants born from 1985 to 1989 and followed up at 7 to 11 years of age. Group II had 51 very low-birthweight infants treated from 1990 to 1994 and followed up at 2 to 5 years of age. Complicated, multiple pregnancy, normal delivery, and extremely low birthweight were significantly more frequent in group II. Very low-birthweight infants were frequently born by cesarean section in severe asphyxia. Only four (7.8%) newborns received surfactant therapy. From 1990 to 1994, respiratory distress syndrome III and IV, and a longer respiratotherapy period were significantly more frequent. From 1985 to 1994, the frequency of sepsis, periventricular leukomalacia, and normal ultrasonography was constant. Intraventricular hemorrhage I, II, and IV were frequently present in the 1990s, and intraventricular hemorrhage III was frequent in the 1980s. Cerebral palsy was diagnosed in 11 (28.9%) children in group I and 18 (35.2%) in group II (not statistically different). Multiple and complicated pregnancy, cesarean section, severe asphyxia, and respiratory distress syndrome did not increase the risk of cerebral palsy in very low-birthweight infants. Periventricular leukomalacia has a more predictive value for cerebral palsy in these infants than did intraventricular hemorrhage.

Cerebral Palsy↗
PubMed2000

Allergic contact dermatitis in patients with anogenital complaints.

OBJECTIVE: Allergic contact dermatitis is a common anogenital disease. STUDY DESIGN: The results of patch testing performed on 1,008 patients evaluated for allergic anogenital contact dermatitis from 21 dermatologic departments in the Information Network of Departments of Dermatology (IVDK) from 1992 to 1997 were analyzed. RESULTS: A final diagnosis of allergic contact dermatitis was made in 351 patients (34.8%). Irritant contact dermatitis was diagnosed in 230 patients (22.8%) and other, nonspecified forms of perianal eczema in 228 patients (22.6%). The remaining cases were due to other distinct dermatologic diseases. Analyzing patch test data from this large group of patients showed that the allergen spectrum resembled that of all patients (54,000) tested from 1992 to 1997. However, dibucaine HCl ranked fourth among contact allergens in the study population. Positive reactions to (chloro-)-methyl-isothiazolinone and to benzocaine were observed more frequently among patients with anogenital complaints as compared to the total IVDK population (3.7% vs. 2.5% and 2.7% vs. 1.5%, respectively). In general, active agents of topical medications and popular remedies, preservatives and ointment bases appeared to cause allergic reactions most frequently. CONCLUSION: Patients with chronic anogenital diseases seem to have a high risk of becoming sensitized. For patch testing we recommend the standard series, dibucaine HCl, propolis, bufexamac and other ingredients from topical preparations according to the patient's history.

Adult↗
PubMed2000

[Monascus purpureus: a new fungus of allergenic relevance].

Anaphylactic reactions to food containing allergens in the consumption or preparation of food are well known. However, allergy in the preparation of sausages have rarely been described. In the present study a 26-year-old butcher was investigated who had a severe anaphylactic reaction developing sneezing, rhinitis, conjunctivitis, generalised pruritus, followed by widespread urticaria, Quincke's oedema and dyspnoe after starting to prepare sausages containing red yield rice. Red yield rice is produced from polished and washed rice by means of the fungus Monascus purpureus. It was the first time that Monascus purpureus could be shown as allergic agent by means of prick-to-prick test, Cellular Antigen Stimulation Test (CAST) and different other immunoblots.

Adult↗
PubMed1999

Impaired ferritin mRNA translation in primary erythroid progenitors: shift to iron-dependent regulation by the v-ErbA oncoprotein.

In immortalized cells of the erythroid lineage, the iron-regulatory protein (IRP) has been suggested to coregulate biosynthesis of the iron storage protein ferritin and the erythroid delta-aminolevulinate synthase (eALAS), a key enzyme in heme production. Under iron scarcity, IRP binds to an iron-responsive element (IRE) located in ferritin and eALAS mRNA leaders, causing a block of translation. In contrast, IRP-IRE interaction is reduced under high iron conditions, allowing efficient translation. We show here that primary chicken erythroblasts (ebls) proliferating or differentiating in culture use a drastically different regulation of iron metabolism. Independently of iron administration, ferritin H (ferH) chain mRNA translation was massively decreased, whereas eALAS transcripts remained constitutively associated with polyribosomes, indicating efficient translation. Variations in iron supply had minor but significant effects on eALAS mRNA polysome recruitment but failed to modulate IRP-affinity to the ferH-IRE in vitro. However, leukemic ebls transformed by the v-ErbA/v-ErbB-expressing avian erythroblastosis virus showed an iron-dependent reduction of IRP mRNA-binding activity, resulting in mobilization of ferH mRNA into polysomes. Hence, we analyzed a panel of ebls overexpressing v-ErbA and/or v-ErbB oncoproteins as well as the respective normal cellular homologues (c-ErbA/TRalpha, c-ErbB/EGFR). It turned out that v-ErbA, a mutated class II nuclear hormone receptor that arrests erythroid differentiation, caused the change in ferH mRNA translation. Accordingly, inhibition of v-ErbA function in these leukemic ebls led to a switch from iron-responsive to iron-independent ferH expression.

5-Aminolevulinate Synthetase↗
PubMed1999

Rate- and site-dependent effects of propafenone, dofetilide, and the new I(Ks)-blocking agent chromanol 293b on individual muscle layers of the intact canine heart.

BACKGROUND: Recent in vitro studies have demonstrated regional differences in electrophysiological properties of individual left ventricular muscle layers. Controversy exists on the relevance of these findings for the situation in vivo. Thus, this study was designed to determine whether the in vivo canine heart exhibits regional differences in left ventricular refractoriness and in the susceptibility to sodium and potassium channel blockers. METHODS AND RESULTS: In 16 dogs, 36 needle electrodes (12 mm long, 4 bipolar electrodes, interelectrode distance 2.5 mm) were inserted into the left ventricular wall. By use of a computerized multiplexer-mapping system, the spread of activation in epicardial, endocardial, and midmyocardial muscle was reconstructed during ventricular pacing at 300- and 850-ms basic cycle length (BCL). Effective refractory periods (ERPs) were determined at baseline and after application of propafenone (2 mg/kg), dofetilide (30 microg/kg), or chromanol 293b (10 mg/kg) by the extrastimulus technique (BCL 300 and 850 ms). At baseline, activation patterns and ERPs were uniform in all muscle layers. Propafenone homogeneously decreased conduction velocity and moderately prolonged ERPs without any regional differences. Dofetilide and chromanol 293b did not affect the spread of activation. Dofetilide exhibited reverse use-dependent effects on ERP, still preserving transmural homogeneity of refractoriness. Chromanol 293b led to a regionally uniform but more pronounced increase in local ERPs at faster than at slower pacing rates. CONCLUSIONS: At the heart rates applied, the in vivo canine heart does not exhibit regional differences in electrophysiological properties. Given the homogeneity of antiarrhythmic drug effects, induction of local gradients of refractoriness is obviously not a common mechanism of proarrhythmia in normal hearts.

Animals↗
PubMed1999

The glucocorticoid receptor is required for stress erythropoiesis.

The glucocorticoid receptor (GR) coordinates a multitude of physiological responses in vivo. In vitro, glucocorticoids are required for sustained proliferation of erythroid progenitors (ebls). Here, we analyze the impact of the GR on erythropoiesis in vivo, using GR-deficient mice or mice expressing a GR defective for transactivation. In vitro, sustained proliferation of primary ebls requires an intact GR. In vivo, the GR is required for rapid expansion of ebls under stress situations like erythrolysis or hypoxia. A particular, GR-sensitive progenitor could be identified as being responsible for the stress response. Thus, GR-mediated regulation of ebl proliferation is essential for stress erythropoiesis in vivo.

Anemia↗
PubMed1999

[A severe epicutaneous test reaction to the bufexamac in a hemorrhoidal therapeutic preparation].

HISTORY AND FINDINGS: A 49-year-old woman presented with acute perianal vesicular/bullous contact dermatitis. Other areas were over the trunk, face, neck and wrists. She reported occasional application of an ointment (Mastu S) to treat her hemorrhoids. INVESTIGATION: Patch tests (basic series, anal block, own ointment, local anesthetic, cosmetics) provoked strong vesicular and bullous reactions of persisting crescendo type, spreading far beyond the site of application, to Bufexamac, to a derivative of hydroxxamine acid, and to local applied ointment with mild or moderate antiinflammatory action. TREATMENT AND COURSE: A week after the patch tests there was a flare-up of the previous foci of dermatitis. These reactions subsided two days later after intravenous injection of prednisolone. The skin lesions healed after rapid reduction of the systemic treatment and local application of corticosteroids, bathing with tanning substances and basic preparations. CONCLUSION: While Bufexamac is not absorbed when applied rectally, perianal contamination may not be avoidable on intra-anal application and can produce sensitization.

Acute Disease↗
PubMed1999

[Giant condylomata acuminata (Buschke-Löwenstein tumor)].

HISTORY AND ADMISSION FINDINGS: A 59-year-old woman had for 3 weeks been suffering from painful, moist skin changes on the external genitals, for 3 months having noticed vegetations in the anogenital and perineal region. She had been fatigued and lacking in energy since then. Her last gynecological examination had been 20 years ago. Examination of the skin on admission revealed extensive plaque and cauliflower-like warts and large areas of maceration in the anogenital region, the labia and perineum, with large areas of maceration. Nodules were clearly palpable in the left labium majora: the inner aspects were markedly reddened and had some cutaneous erosions. These findings suggested giant condyloma (GC; Buschke-Löwenstein tumour). INVESTIGATIONS: Biopsy showed marked condylomatous epithelial proliferations which, with the formation of markedly thickened epithelial cones, had reached the stage of a verrucous carcinoma. TREATMENT AND COURSE: Under local anti-inflammatory and adstringent medications the inflammatory reaction quickly subsided. Vulvectomy was performed to remove the tumour. CONCLUSION: Giant condyloma (Buschke-Löwenstein tumour) is a rare pseudocancereous lesion. If human papilloma viruses of type 16 or 18 is demonstrated in the lesions, malignant degeneration should be considered. Histological examination is essential to differentiate it from squamous cell carcinoma.

Carcinoma, Verrucous↗
PubMed1999

Liver-specific imaging with SHU 563A: diagnostic potential of a new class of ultrasound contrast media.

The purpose of this study was to evaluate the imaging properties and diagnostic potential of the novel polymeric ultrasound contrast agent SHU 563 A. After i. v. injection, the agent circulates in the blood pool for about 10 min and is then subsequently sequestered by the RES cells predominantly in the liver. The acoustic emission capabilities enable a very sensitive detection during the blood pool phase and after uptake in the RES cells, contributing to differential diagnosis as well as detection of liver lesions. During a multicenter study, 28 patients with liver lesions were examined. In all patients the results were compared to baseline ultrasound and Contrast enhanced Spiral CT. With respect to lesion size and location, very good agreement between SHU 563 A ultrasound and Spiral CT was achieved. Additional lesions could be shown in the RES phase by SHU 563 A enhanced ultrasound. 26 further patients were examined in other indications. The results in all 54 patients indicate good safety and tolerance of SHU 563 without limitations for diagnostic use. SHU 563 A enhanced ultrasound adds significantly to the detection and delineation of focal liver lesions by improving conspicuity due to RES based contrast after uptake.

Adenocarcinoma↗
PubMed1999

Wideband harmonic imaging: a novel contrast ultrasound imaging technique.

A novel ultrasonic imaging method, wideband harmonic imaging, for nonlinear imaging of microbubble contrast agents is evaluated. In wideband harmonic mode, two pulses of alternate phase are send out. The image is then processed from the sum of both pulses, resulting in an image of nonlinear scatterers such as microbubbles. A prototype ultrasound system, Siemens Elegra, was evaluated with in vitro investigations and animal trials, using conventional, harmonic and wideband harmonic settings with the galactose based ultrasound contrast agent Levovist. Wideband harmonic imaging offers superior sensitivity for ultrasound contrast agents compared to conventional imaging and harmonic imaging. At low transmit power settings (MI 0. 1-0.5) the nonlinear response is already sufficient to generate a image of the blood pool distribution of Levovist in the rabbit kidney including the microvasculature, with clear delineation of vessels and perfused parenchyma. At high transmit amplitudes, nonlinear tissue response reduced the apparent image contrast between contrast agent and tissue. The results suggest that wideband harmonic imaging is currently the most sensitive contrast imaging technique, maintaining highest spatial resolution. This may add to image quality and offer new clinical potential for the use of ultrasound contrast agents such as Levovist.

Animals↗
PubMed1999

The Saccharomyces cerevisiae LEP1/SAC3 gene is associated with leucine transport.

Leucine uptake by Saccharomyces cerevisiae is mediated by three transport systems, the general amino acid transport system (GAP), encoded by GAP1, and two group-specific systems (S1 and S2), which also transport isoleucine and valine. A new mutant defective in both group-specific transport activities was isolated by employing a gap1 leu4 strain and selecting for trifluoroleucine-resistant mutants which also showed greatly reduced ability to utilize L-leucine as sole nitrogen source and very low levels of [14C]L-leucine uptake. A multicopy plasmid containing a DNA fragment which complemented the leucine transport defect was isolated by selecting for transformants that grew normally on minimal medium containing leucine as nitrogen source and subsequently assaying [14C]L-leucine uptake. Transformation of one such mutant, lep1, restored sensitivity to trifluoroleucine. The complementing gene, designated LEP1, was subcloned and sequenced. The LEP1 ORF encodes a large protein that lacks characteristics of a transporter or permease (i.e., lacks hydrophobic domains necessary for membrane association). Instead, Lep1p is a very basic protein (pI of 9.2) that contains a putative bipartite signal sequence for targeting to the nucleus, suggesting that it might be a DNA-binding protein. A database search revealed that LEP1 encodes a polypeptide that is identical to Sac3p except for an N-terminal truncation. The original identification of SAC3 was based on the isolation of a mutant allele, sac3-1, that suppresses the temperature-sensitive growth defect of an actin mutant containing the allele act1-1. Sac3p has been previously shown to be localized in the nucleus. When a lep1 mutant was crossed with a sac3 deletion mutant, no complementation was observed, indicating that the two mutations are functionally allelic.

Alleles↗
PubMed1999

Stimulated acoustic emission to image a late liver and spleen-specific phase of Levovist in normal volunteers and patients with and without liver disease.

Quantitative studies were performed to investigate liver- specific uptake of the microbubble Levovist, using stimulated acoustic emission (SAE), which can detect microbubbles even when stationary or slow-moving. These comprised studies of biodistribution comparing the liver and kidney in five normal volunteers, reproducibility in 34 patients, comparison between cirrhotics and controls (n = 9 each) and maximal depth of effect at different frequencies (180 measurements in 31 patients). Stimulated acoustic emission lasted beyond 30 min, with strongly liver-specific properties in each volunteer and was highly reproducible. No difference in the amount of SAE in the superficial liver was seen between cirrhotic and normal livers, but attenuation was higher in cirrhotics. This demonstrates a frequency-dependent effect on liver SAE penetration. We conclude that the liver uptake of Levovist lasts over 30 min, is reproducible, occurs even where diffuse liver disease is present and can be used to assess tissue attenuation in a novel fashion.

Adult↗