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T Fuchs

Publications and source records attributed to T Fuchs.

At least 37 records · Page 2Linked to original sources
PubMed2001

Precise amounts of a novel member of a phosphotransferase superfamily are essential for growth and normal morphology in Caulobacter crescentus.

The Caulobacter crescentus chromosomal clp locus contains the genes encoding the components of ClpXP, a multisubunit protease required for cell cycle progression in this organism. Here, we report the identification and characterization of cicA, a gene located between the clpX and clpP genes on the Caulobacter chromosome. cicA is a novel morphogene in C. crescentus and, like clpX and clpP, is essential for growth. A conditional cicA mutant stopped growth, but retained viability under restrictive conditions. In contrast, an increased concentration of CicA led to an immediate loss of the normal rod shape, an almost 10-fold increase of the cell's volume and a cell division block. In parallel with this drastic morphological change, cells rapidly lost viability. Primary sequence analysis suggested that the cicA gene encodes a member of a large superfamily of phosphotransferases, that include phosphoserine phosphatases, the ATPase domain of P-type ATPases and receiver domains of response regulators. Four conserved motifs of this protein family that have been implicated in the catalysis of phosphotransfer reactions were investigated by site-directed mutagenesis and were found to be critical for in vivo function of CicA. Based on our observations, we postulate that CicA is involved in essential phosphotransferase reactions in Caulobacter and that increased activity of CicA has a deleterious effect on cell wall biosynthesis, morphogenesis and cell division.

Adenosine Triphosphatases↗
PubMed2001

[Allergen immunotherapy - a position paper of the German society for allergology and clinical immunology].

Mechanisms of allergen immunotherapy (AIT) are complex inducing numerous immunological effects. Successful AIT is most likely based on a functional switch of and tolerance induction in specific T cells downregulating allergic hypersensitivity and inflammation. Subcutaneous AIT for allergic rhinoconjunctivitis and allergic asthma has been successfully assessed in controlled studies with several clinically important allergens (i. e. birch-, grass- and mugwortpollen, dust mites, animal dander) and has shown convincing clinical efficacy. Considered as the only causal treatment besides allergen avoidance at present, AIT can alter the natural course of allergic diseases. Hymenopteravenom hypersensitivity (to bee- and wasp venom) treated with AIT gives the best results compared to AIT with other allergens. AIT is indicated in patients with IgE-mediated sensitizations and corresponding clinical symptoms to allergens, which do not or hardly permit allergen avoidance and which are available as suitable extracts. Decisions about indication and allergen selection should only be made by a physician with certified training or qualified knowledge and skills in allergology. AIT is administered by physicians experienced in this therapy. After addressing tolerability and present status of health the recommended or individually adjusted does is injected and precisely documented, followed by a mandatory waiting period of 30 minutes. Indication for and application of AIT in children are quite similar compared to the treatment of adults. Children tolerate AIT very well and benefit especially from its immunomodulatory effects. Risk factors for and results of unwanted systemic effects can effectively be minimized by training of the staff members involved, adhering to safety standards and immediate emergency treatment. Modified allergens, recombinant proteins and immunomodulatory adjuvants created by basic research are promises for an improved efficacy of AIT with reduced unwanted effects in the future.

Allergens↗
PubMed2001

Patch testing of nickel sulfate and potassium dichromate with a standardized ready-to-use test system gives highly reproducible results: a double-blind multicentre study.

There is still some doubt about the reproducibility of patch tests. A sound assessment needs optimized and unbiased studies. This study analysed the results of a double-blind multicentre study with nickel sulfate and potassium dichromate patch tests attached synchronously to both sides of the back of patients with a history of nickel allergy, conducted with a highly standardized randomized test system (TRUE-test). Out of 589 patients tested, a total of 388 had responded with allergic reactions to nickel sulfate and 130 to potassium dichromate. The reproducibility of positive nickel (dichromate) patch tests was 99.2% (90.8%). The reaction index was also calculated, which relates the number of allergic reactions obtained with a test preparation to the number of questionable and irritant reactions; the reaction index can range from -1 (questionable and irritant reactions only occur) to 1 (allergic reactions only occur). For nickel sulfate the reaction index was 0.91, but it was only 0.23 for potassium dichromate, as a result of considerably more questionable reactions. In conclusion, a highly synchronous reproducibility of results can be achieved by using a well-standardized patch-test system, especially with nickel sulfate. However, distinct allergens and test systems need to be evaluated separately.

Adult↗
PubMed2001

Advanced single-slice rebinning for tilted spiral cone-beam CT.

Future medical CT scanners and today's micro CT scanners demand cone-beam reconstruction algorithms that are capable of reconstructing data acquired from a tilted spiral trajectory where the vector of rotation is not necessarily parallel to the vector of table increment. For the medical CT scanner this case of nonparallel object motion is met for nonzero gantry tilt: the table moves into a direction that is not perpendicular to the plane of rotation. Since this is not a special application of medical CT but rather a daily routine in head exams, there is a strong need for corresponding reconstruction algorithms. In contrast to medical CT, where the special case of nonperpendicular motion is used on purpose, micro CT scanners cannot avoid aberrations of the rotational axis and the table increment vector due to alignment problems. Especially for those micro CT scanners that have the lifting stage mounted on the rotation table (in contrast to setups where the lifting stage holds the rotation table), this kind of misalignment is equivalent to a gantry tilt. We therefore generalize the advanced single-slice rebinning algorithm (ASSR), which is considered a very promising approach for medical cone-beam reconstruction due to its high image quality and its high reconstruction speed [Med. Phys. 27, 754-772 (2000)], to the case of tilted gantries. We evaluate this extended ASSR approach (which we will denote as ASSR+, for convenience) in comparison to the original ASSR algorithm using simulated phantom data for reconstruction. For the case of nonparallel object motion ASSR+ shows significant improvements over ASSR, however, its computational complexity is slightly increased due to the broken symmetry of the spiral trajectory.

Algorithms↗
PubMed2001

[Ultrasonographic assessment of cervical length and measurement of fetal fibronectin level in cervical secretion of pregnant women in prophylaxis of premature deliveries].

OBJECTIVE: The aim of this study was to assess the usefulness of the assessment of cervical length and and measurement of fetal fibronectin level in cervical secretion of pregnant women in prophylaxis of premature deliveries. MATERIAL AND METHODS: 78 pregnant women hospitalized in Department of Fertility and Obstetrics, University School of Medicine Wrocław. They were divided into III groups: Group I-13 pregnant women who had premature delivery and the time between examination and delivery was no longer than 24 hours. Group II-20 women who had premature delivery, and the time between examination and delivery was longer than 24 hours. Group III-pregnant who delivered at term (control group). Between the 25th and the 34th week of pregnancy presence of fetal fibronectin in cervical secretion and ultrasonographic assessment of cervical length were done. RESULTS: Significantly higher percentage of women with presence of fibronectin in cervical secretion and significantly shorter length of cervical length was stated in 13 pregnant women who delivered prematurely, between the 28th and 35th week of pregnancy comparing with other groups. In group II pregnant women delivered between the 28th and 35th week of pregnancy, and the time between examination and delivery was from 3 days to 4 weeks. In this group in 75% examined women fibronectin was present in cervical secretion. Significant was that cervical length in 14 of this group of women (70%) was no longer than 20 mm and in the rest was between 20-30 mm, moreover in no cases was longer than 30 mm. In group III only in 7% women presence of fibronectin in cervical secretion was stated and only in two cases (4%) cervical length was shorter than 20 mm, both of them delivered in 38th week of pregnancy. CONCLUSIONS: 1. Examination of fetal fibronectin in cervical secretion allows precisely estimate the risk of premature delivery. 2. Cervical length shorter then 20 mm collerates with the presence of fetal fibronectin in cervical secretion and with increased risk of premature delivery.

Case-Control Studies↗
PubMed2001

[The course of pregnancy, delivery and puerperium in women with varices and thrombophlebitis of lower extremities, after application of low molecular weight heparins].

OBJECTIVES: Estimation of the long term prophylactic or therapeutic application of low molecular weight heparin (LMWH) on the platelets count, and incidence bleedings during pregnancy, delivery and puerperium in the women with varices of lower extremities and past thrombophlebitis of lower extremities. MATERIAL AND METHODS: 5212 pregnant, women in labour and in puerperium divided into 4 groups.; 142 women with varices and thrombophlebitis of lower extremities (group I); 10 with past thrombophlebitis of lower extremities (group II); 15 with thrombophlebitis in current pregnancy; 5045 without vascular complications (group IV--control). In group I during pregnancy compression therapy was applied (stockings) and low molecular weight heparins (LMWH) in course of puerperium. In group II during the 1st trimester of pregnancy and in labour the same heparin doses were administered, while the doses were increased in the 2nd and 3rd trimester. In group III, when thrombophlebitis was stated non-steroid anti-inflammatory drugs and LMWH were administered. In all cases treated with heparin both number of platelets and incidents of bleedings from genitourinary tract were observed. Presence of embolic complications was also noted. RESULTS: No cases of decrease platelets number or bleedings from genitourinary tract were observed in group I-III during administering of LMWH. In women in group II where prophylactic with LMWH was applied no incidences of recurrent thrombophlebitis during pregnancy and puerperium were observed. In group I-III all newborns were born in good condition and no complications were observed. Average blood loss during both labour and cesarean section, among women in group I-III was not significantly different comparing with control group. No incidences of pulmonary artery embolism or decrease number of platelets were observed. CONCLUSIONS: 1. The long term prophylactic or therapeutical administration of LMWH in the women with varices of lower extremities or thrombophlebitis has no influence on the platelets count and incidence of bleedings from genitourinary tract during pregnancy or increase of blood loss during labour and puerperium. 2. In the women with past thrombophlebitis of the lower extremities after application of LMWH during pregnancy there were no recurrence observed.

Adult↗
PubMed2000

Technical advances in multi-slice spiral CT.

X-ray computerised tomography (CT) scanning with continuous patient transport has been established under the name Spiral CT since several years as the standard clinical examination procedure. This technique has been improved continuously with respect to scan speed, temporal response and z-axis resolution by the use of latest technical developments: Rotation times up to 0.5 s and multi-row detector array systems. Today detector systems with M + 4 simultaneously measured slices are available. We report about recent progress of spiral CT reconstruction algorithms that are based on multi-slice data. It is demonstrated that the new technology not only provides significant reduction in overall scan times and thereby of the CT scanner?s X-ray tube load; beyond that, the new technology allows CT imaging of the beating heart with high level image quality in standard clinical routine.

Algorithms↗
PubMed2000

Positive nickel patch tests do not intensify positive reactions to adjacent patch tests with dichromate. Results from a double-blind multicentre study of the German Contact Dermatitis Research Group (Deutsche Kontaktallergie-Gruppe, DKG).

The possible interference of neighbouring allergic patch-test reactions is still an open question. In this study, we investigated whether there is a distance-related mutual modification of neighbouring allergic patch-test reactions to nickel sulfate and potassium dichromate. We used a double-blind multicentre study design with randomized attachment of special TRUE Tests with 1, 3 and 7 cm distance between nickel sulfate and potassium dichromate patches. 589 patients with a history of nickel allergy (523 female, 66 male) were tested, with a mean age of 35 years. A log-linear modelling approach was used for statistical assessment of the relation between the distance separating neighbouring patch tests with nickel and dichromate and the reactions to the allergens. Non-reproducibility coefficients were compared by the generalized version of Fisher's exact test for arbitrary 2-dimensional contingency tables. For the left side of the back, virtually no differences (p=0.70) were found in the reaction patterns obtained for the 3 distances separating nickel and dichromate patch tests. On the right side of the back, the number of reactions to dichromate patches with only 1 cm distance from moderate/strong nickel reactions was lower than the number of positive dichromate tests at larger distances from nickel tests (on the border of statistical significance: p= 0.05). Corresponding side-related results were obtained for subgroups of patients with and without a history of atopic dermatitis. The non-reproducibility of reactions to dichromate was not significantly related to the distance between neighbouring tests. Our data argue against a "spillover" effect of strong/moderate nickel reactions, but indicate that such reactions may, under certain conditions, attenuate adjacent reactions to an unrelated allergen. In the case of future verification, this will have implications for the interpretation of patch tests.

Adolescent↗
PubMed2000

Prevention of latex allergy by selection of low-allergen gloves.

BACKGROUND: In recent years the prevalence of type I allergy to latex has continuously increased, in particular among healthcare workers, to about 10%. While most forms of type I allergy caused by other environmental allergens can be treated by pharmacotherapy or specific immunotherapy, minimizing exposure to latex proteins may represent an effective preventive measure for latex allergy. OBJECTIVE: To investigate whether it is possible to select by in vitro and in vivo testing low-allergen latex gloves for prevention of latex allergy. METHODS: We obtained separate extracts by standard aqueous extraction from the inner and outer surfaces of 15 different commonly used (10 examination, five surgical) glove brands. The extracts were analysed by quantitative (bicinchoninic protein assay, immunoglobulin [Ig] E-ELISA, ELISA competition) and qualitative (SDS-PAGE, silver staining, IgE immunoblotting) methods for their protein and allergen contents. In addition, the glove extracts were analysed for their capacity to induce basophil histamine release and immediate skin reactions. RESULTS: Extracts from different glove brands contained cross-reactive IgE epitopes. However, IgE binding studies, basophil histamine release and skin testing showed that different glove brands and their inner and outer surfaces contained widely varying protein and allergen contents. While the determination of total protein contents was not sufficient to identify low-allergen gloves, IgE measurements, basophil histamine release and skin testing were in good agreement and allowed to select low-allergen products. CONCLUSION: We suggest the use of low-allergen latex products identified by IgE binding, basophil histamine release assays and skin testing as a feasible preventive measure for latex allergy.

Adolescent↗
PubMed2000

In situ localization of latex allergens in 3 different brands of latex gloves by means of immunogold field emission scanning and transmission electron microscopy.

BACKGROUND: Latex proteins represent relevant allergens, particularly for those persons who are frequently exposed to latex products (eg, health care workers and patients with chronic disorders). Although several latex allergens have been characterized by biochemical and molecular biologic techniques, little information is available concerning the in situ localization of allergenic proteins in latex products. OBJECTIVE: The objective of the present study was the in situ localization of latex allergens. METHODS: Serum IgE from patients with latex allergy reacting with a broad range (5-200 kd) of latex allergens was used for the in situ localization of latex allergens. One surgical and 2 examination latex glove brands were investigated by using immunogold field emission scanning and transmission electron microscopy. RESULTS: Allergens were detected on the inner and outer surface of the gloves, particularly near the edges, crests, or folds of the bleb-like structures visible on the surface of the latex material at high magnifications. In ultrathin cross-sections, latex allergens were found throughout the sections. CONCLUSIONS: Latex allergens were localized on the outer and inner surface but also in the interior of latex gloves. The occurrence of latex allergens on the surface of latex products may be related to their potential to induce local reactions and, perhaps, to sensitize individuals by means of contact.

Allergens↗