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K Krüger

Publications and source records attributed to K Krüger.

At least 55 records · Page 3Linked to original sources
PubMed1999

[Kaposiform HHV-8 negative acroangiodermatitis in chronic venous insufficiency].

A 76-year-old female patient developed severe manifestations of a kaposi-like acroangiodermatitis (so-called Mali's disease) due to chronic venous insufficiency of the lower extremities. The patient presented with large areas of confluent, violaceous or brown-black papules on both lower legs. Histologically, proliferation of thick-walled capillaries was seen in the upper dermis consisting of fully differentiated endothelial cells, as shown by immunohistochemistry. In contrast to true Kaposi's sarcoma, human-herpes-virus-8 DNA could not be detected by polymerase-chain-reaction in this condition. We review the diagnostic criteria used to distinguish between acroangiodermatitis, also called pseudo-Kaposi's sarcoma, and the true Kaposi's sarcoma.

Acrodermatitis↗
PubMed1999

Cloning and functional expression of the D-beta-hydroxybutyrate dehydrogenase gene of Rhodobacter sp. DSMZ 12077.

Nucleotide sequence and biochemical analysis of D-beta-hydroxybutyrate dehydrogenase (EC 1.1.1.30), isolated from Rhodobacter sp., indicate functional oligomers composed of subunits of 257 amino acids with a calculated M(r) of 26,800 and a pI of 5.90. Compared to mammalian short-chain alcohol dehydrogenases, the bacterial enzyme lacks a C-terminal lipid anchor domain and was found to be highly active upon expression in Escherichia coli even without lipid supplement. The recombinant enzyme could be highly enriched using a single chromatography step and was shown to be stable over a broad range of pH and temperature.

Animals↗
PubMed1999

Basal cell carcinoma possibly originates from the outer root sheath and/or the bulge region of the vellus hair follicle.

In the present study, the immunophenotype of basal cell carcinoma was analysed in comparison with human vellus hair follicular keratinocytes. We also established the lectin binding profile of basal cell carcinoma and human vellus hair follicles (VHF), using several lectins with different sugar specificities. Our findings showed an almost identical immunohistochemical profile for basal cell carcinoma and the suprabulbar region of the outer root sheath of VHF, whereas other follicular compartments such as the bulbar, the isthmus or the supraseboglandular regions did not correlate. In particular, homogeneous and constant expression of the basal differentiation markers CK 5 and CK 14 were found in both specimen, with no expression of the simple epithelium type keratin CK 8 and the suprabasal differentiation markers CK 1 and CK 10. CK 19 showed variable expression in basal cell carcinoma, with constant expression in the outer root sheath and the follicular bulge regions, but was always absent in interfollicular epidermal keratinocytes. In addition, the lectin binding profiles of basal cell carcinoma and the outer root sheath in the suprabulbar region of human VHF were comparable, with the presence of binding sites for PNA, Con A and WGA. These findings provide evidence for a histochemical relationship between basal cell carcinoma and the follicular epithelium of VHF which is closer than that with the epidermis, and suggest its possible origin from or possibly its differentiation pattern towards the cells of the outer root sheath and/or the follicular bulge region of the VHF.

Basal Cell Carcinoma↗
PubMed1999

[The MR tomographic imaging of uncomplicated secondary fracture healing exemplified by the distal radius fracture].

PURPOSE: To investigate the normal sequential MR-pattern of uncomplicated fracture healing within the first 6 weeks. METHODS: In 8 patients with distal radius fracture, 4 by 4 with and without intraarticular fracture, MR examinations were performed 3-4 days after the onset of fracture and after 1, 2, 3, 4, 5 and 6 weeks using the following techniques: T1-weighted spin echo, T2-weighted spin echo, T2 proton density weighted, STIR (short inversion time inversion recovery), T2-weighted turbo spin-echo and fast field echo (FFE, gradient echo). Sequential examinations were analysed regarding 1) the appearance of fracture line, 2) development of bone marrow signal, and 3) signal changes in surrounding soft tissue. Maximum contrast of bone marrow and soft tissue was measured. RESULTS: The fracture line in bone marrow was best detectable in FFE- and T2-weighted spin ech images during the first week and in T2-weighted fast spin echo and proton density-weighted images from the 2nd to 4th week. Beginning in the 5th-6th week an increase of signal intensity in the fracture gap was typical in all sequences except for T1-weighted spin echo. The contrast maximum of bone marrow and soft tissue, best detectable in STIR- and T2-weighted spin echo images, occurred in the 1st-2nd week. CONCLUSIONS: MRI shows a typical time-depending pattern of the fracture line, surrounding bone marrow and soft tissue in normal fracture healing. The degree of injury influences the development of signal changes.

Adult↗
PubMed1999

The effect of male occupational exposure in infertile couples in Norway.

The objective of the study was to assess whether reduced semen quality in infertile couples is associated with occupational exposures known to be hazardous to fertility. Results of the first semen analysis were linked to occupational exposure data from a self-administered questionnaire. Reduced semen quality was found in men exposed to electromagnetic fields (odds ratio, 3.22; confidence interval, 1.46 to 7.09). A tendency toward reduced semen quality was seen in commuters (OR, 1.52; CI, 0.89 to 2.59), shift workers (OR, 1.46; CI, 0.89 to 2.40), and men exposed to heavy metals (OR, 1.47; CI, 0.76 to 2.87). In general, the impact of occupational exposure on semen quality in infertile couples in Norway seemed to be minor. However, occupational exposure mapping is still important in individual infertility investigations.

Adult↗
PubMed1999

Myocardial fibrosis in polymyositis.

Myocardial involvement in polymyositis is commonly suspected in noninvasive studies, but symptomatic cardiac disease is rare. We describe a 27-year-old woman with a 6 year history of severe polymyositis and persistent elevation of creatine phosphokinase-MB isoenzyme who suddenly developed congestive heart failure and bradycardia-tachycardia syndrome. Autopsy revealed severe myocardial fibrosis without inflammatory cell infiltrates concomitant to active polymyositis of the skeletal muscles despite intensive longterm immunosuppressive therapy.

Adult↗
PubMed1998

New modular delivery system for diagnostic and therapeutic pre-targeting using tautomer-specific monoclonal antibody EM-6-47 and 3-substituted adenines.

We have developed a new modular affinity system for the 2-step delivery of functional molecules to target cells. The system is based on the tautomer-specific monoclonal antibody (MAb) EM-6-47, which binds to 3- and 3,8-substituted adenines with high affinity (Ka > 10(9) l/mol) without cross-reacting with naturally occurring purine derivatives. This MAb serves as the hapten-specific fusion partner to produce bispecific MAbs (bs-MAbs) recognizing a target cell antigen and a low-m.w. hapten as carrier molecule for, e.g., radionuclides. Either the C-8 or the N-3 position of adenines can be used for conjugation with effector molecules; the remaining position may be substituted with different moieties to modulate the pharmacokinetics of the haptens. Different 3- and 3,8-substituted adenines conjugated to the chelates DOTA and DTPA or to the drug daunomycin were synthesized. Adenine-chelate derivatives were efficiently labeled with (111)In and 90Y, while high-affinity binding of 3-substituted adenines to MAb EM-6-47 remained almost unaffected by the conjugation to radiochelates. To confirm the validity of the delivery system, a prototype bs-MAb, EM-168-47, was generated by somatic cell fusion of MAb EM-6-47 and MAb EM-168-2, the latter recognizing a surface antigen on canine hematopoietic cells. Two-step targeting assays in vitro verified the bs-MAb-mediated, dose-dependent delivery of (111)In-labeled adenine-chelate derivatives to myeloid cells. This system represents a powerful tool for new pre-targeting approaches relying on bs-MAbs and low-m.w. haptens. Suitable cellular antigens can be targeted by fusing the appropriate MAbs with hapten-specific MAb EM-6-47, and tailor-made 3-substituted adenines may be labeled with diagnostic or therapeutic radionuclides, cytotoxic drugs or other functional molecules.

Adenine↗
PubMed1998

The transcriptional activator GvpE for the halobacterial gas vesicle genes resembles a basic region leucine-zipper regulatory protein.

The GvpE protein involved in the regulation of gas vesicles synthesis in halophilic archaea has been identified as the transcriptional activator for the promoter located upstream of the gvpA gene encoding the major gas vesicle structural protein GvpA. A closer inspection of the GvpE protein sequence revealed that GvpE resembles basic leucine-zipper proteins typically involved in the gene regulation of eukarya. A molecular modelling study of the C-terminal part implied a cluster of basic amino acid residues constituting the DNA-binding site (DNAB) followed by an amphiphilic helix, suitable for the formation of a leucine-zipper structure within a GvpE dimer. The model of a GvpE dimer docked onto DNA indicated that the side-chains of the basic residues could perfectly interact with the negatively charged phosphate groups of the DNA backbone. Substitution of three basic amino acid residues of this putative DNAB by alanine and/or glutamate generated mutated GvpE proteins. None of these was able to activate the c-gvpA promoter in vivo, indicating that these basic residues are required for GvpE activity. This identification of an archaeal gene regulator displaying similarity to eukaryal regulatory proteins implies that the basic transcription machinery of eukarya and archaea are closely related, and that the regulatory proteins have evolved according to common principles.

Amino Acid Sequence↗
PubMed1998

Reproductive outcome in offspring of parents occupationally exposed to lead in Norway.

In Norway, great efforts have been made to protect both male and female employees against teratogenic exposures. Associations between occupational lead exposure and reproductive outcome in the offspring were studied. All births in Norway 1970-1993 with possible maternal or paternal occupational lead exposure were compared with a reference population of offspring of parents without occupational lead exposure. Offspring of lead exposed mothers had an increased risk of low birth weight (RR = 1.34; CI = 1.12-1.60) and neural tube defects (RR = 2.87; CI = 1.05-6.38). Effects on birth weight and gestational age showed significant dose-response associations. Offspring of lead exposed fathers had no increased risks of any of the analyzed reproductive outcomes. However, decreased risks were observed of low birth weight (RR = 0.91; CI = 0.86-0.96) and preterm birth (RR = 0.89; CI = 0.86-0.93). Further efforts seem to be needed to protect the offspring of lead-exposed mothers.

Birth Weight↗
PubMed1998

[Severe toe gangrene as an early manifestation of Wegener granulomatosis in a young patient].

Gangrene of digits is a very rare manifestation of Wegener's granulomatosis (WG). We report a case of a 29-year-old woman with nonspecific symptoms like fever, weight loss, arthralgia, arthritis and high systemic inflammatory signs. On the grounds of a presumed infection the patient was treated with antibiotics which showed no effect. Within short she complained of pain and paresthesia of the right foot with a rapid lividity. Angiography demonstrated multiples stenoses and multisegmental occlusions of the lower leg arteries. Together with renal and pulmonal symptoms a WG was suspected, the diagnosis being confirmed by kidney biopsy and positive cANCAs. A few months after starting a combined therapy with cyclophosphamide and corticosteroids the patient showed a partial remission with a residual toe gangrene. Comparing the five worldwide reported cases with digital gangrene and our presentation there is a concordance of all in the occurrence of an extremely high disease activity together with a glomerulonephritis. The findings of p-ANCAs in our patient and positive Hbs antigen in another case of WG with digital gangrene suggests a relation to panarteriitis nodosa, where gangren is more common.

Adult↗
PubMed1998

[Need and possibilities for quality management in drug therapy of patients with rheumatic diseases].

Only during recent years have intensive attempts been made to install a program for more objectively based quality criteria instead of the traditional subjectively and empirically determined therapeutic decisions for the application of DMARDs. The optimized quality management for this treatment should focus on factors such as: diagnosis as early as possible (basic for the introduction of DMARD therapy), reliable assessment of the individual long-term prognosis (as an important aid in the choice of the appropriate drug), prompt determination and establishment of the chosen therapy, and an optimal long-term application of this treatment (including competent control of effectiveness, tolerance, and compliance). Instrumentation for these purposes have been so far only partly available, e.g., diagnostic criteria and control guidelines. Besides the partially missing appropriate measures, maximum quality management is presently opposed by insufficient rheumatological specialist care for many RA patients--caused by the lack of specialists and a dilatory attitude towards involving them, respectively. Nevertheless, there is hope that in the course of new developments the gap between needs and benefits of quality management will grow smaller.

Antirheumatic Agents↗
PubMed1998

Lactate in scalp and cord blood from fetuses with ominous fetal heart rate patterns.

OBJECTIVE: We investigated lactate concentrations in fetal scalp and cord blood to determine the sources of fetal lactacidosis in fetuses with ominous heart rate patterns. METHODS: Cord blood was collected from newly delivered infants who had been monitored by fetal scalp blood sampling during labor. In 250 cases umbilical arterial and venous cord blood lactate levels were measured. We assessed the umbilical arterial lactate concentrations in relation to the venous lactate levels, the arterial pH level, base excess, and arteriovenous lactate differences in cord blood. In 103 cases the levels of lactate in fetal scalp blood, sampled within 60 minutes of delivery, were compared with those in the umbilical artery and vein and the pH level and base excess immediately after birth. RESULTS: Lactate level in the umbilical artery showed a significant correlation to that in umbilical venous blood (r = .84, P < .001), to arteriovenous lactate differences (r = .52, P < .001), as well as to pH (r = -.55, P < .001) and base excess (r = -.63, P < .001) in arterial cord blood. Lactate concentrations in fetal scalp blood shortly before delivery showed a significant correlation to lactate levels in the umbilical arterial (r = .65, P < .001) and venous blood (r = .62, P < .001). CONCLUSION: The study indicates a close correlation between lactate levels in arterial and venous cord blood, as well as between the lactate levels and pH and base excess in cord arterial blood in patients with ominous fetal heart rate patterns. We also found an increased fetal contribution with increasing lactacidemia. Lactate concentrations in fetal scalp blood correlated well with those in cord arterial and venous blood.

Female↗
PubMed1998

Anisotropy of chemical shift and J coupling for P-31 and Se-77 in trimethyl and triphenyl phosphine selenides.

The 31P and 77Se magic angle spinning (MAS) nuclear magnetic resonance (NMR) experiments for selenium-77 enriched (70%) trimethylphosphine selenide 1 and triphenylphosphine selenide 2 were carried out in order to determine the nuclear magnetic shielding tensors of both nuclei and to establish values of the phosphorus-selenium indirect spin-spin coupling anisotropy delta J. The m = +1/2 and m = -1/2 subspectra were analysed by the dipolar-splitting-ratio method of Eichele and Wasylischen. For the C(S) molecule 1, delta J was obtained to be +640 +/- 260 Hz from the 31P spectrum and +550 +/- 140 Hz from the 77Se spectrum. Density functional theory (DFT) calculations give a delta J value of about +705 Hz. The value of delta J could not be determined unambiguously by analysis of the 31P spectra for the C1 molecules 2; nevertheless, an estimation of delta J was possible. The principal axis 3 of the phosphorus shielding tensor was determined to be nearly parallel to the PSe bond in 1 and 2. For the selenium shielding of 1, the same orientation was found, whereas in 2, the principal axis 2 of the selenium shielding was found to be oriented nearly along the PSe bond. The experimentally determined phosphorus nuclear magnetic shielding tensors agree well with those calculated by the IGLO method. For those two principal values of the selenium-shielding tensors corresponding to directions nearly perpendicular to the SeP bond, the agreement between calculated and experimental values is satisfactory. For the third one, corresponding to the principal axis close to the SeP bond, the calculated deshielding contributions are distinctly too small for both compounds investigated. Trends observed for the calculated molecular orbital (MO) contributions to the shielding as well as possible reasons for the underestimation of the deshielding contributions along the SeP bond are discussed.

Anisotropy↗
PubMed1998

[Direct-current treatment of chemically induced mammary carcinoma in an animal model: MR volumetric assessment of the effect of the therapy].

PURPOSE: To investigate the effect of direct current treatment (DCT) on the growth of mammary carcinomas in rats by MR-volumetry. METHODS: Chemically induced mammary adenocarcinomas in a control group (n = 17) were compared with treated tumours (18 C/cm3 in group A: n = 7 or 36 C/cm3 in group B: n = 12). 31 untreated tumours were situated near a treated tumour (group C). Experiments were carried out using one positive electrode in the tumour centre and three negative electrodes in the periphery. The tumour volume was measured by MRI before, and 1, 3, 6, 9 and 12 weeks after treatment. RESULTS: 12 weeks after DCT, the mean tumour volume in group A (164% +/- 158%, p < 0.05) and group B (13% +/- 24%, p < 0.001) was significantly reduced compared to the control group (434% +/- 230, Mann-Whitney U-Test). Complete tumour regression occurred in 42% of tumours in group B and was not achieved in group A, C and control group. Tumour growth in group C was decreased compared to the control group. CONCLUSIONS: The effectiveness of DCT was found to depend on the applied dosage -36 C/cm3 was more effective than 18 C/cm3. The effect of DCT is not limited to the area between the electrodes.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1998

Reperfusion after thrombolytic therapy of embolic stroke in the rat: magnetic resonance and biochemical imaging.

The effect of thrombolytic therapy was studied in rats submitted to thromboembolic stroke by intracarotid injection of autologous blood clots. Thrombolysis was initiated after 15 minutes with an intracarotid infusion of recombinant tissue-type activator (10 mg/kg body weight). Reperfusion was monitored for 3 hours using serial perfusion- and diffusion magnetic resonance imaging, and the outcome of treatment was quantified by pictorial measurements of ATP, tissue pH, and blood flow. In untreated animals, clot embolism resulted in an immediate decrease in blood flow and a sharp decrease in the apparent diffusion coefficient (ADC) that persisted throughout the observation period. Thrombolysis successfully recanalized the embolized middle cerebral artery origin and led to gradual improvement of blood flow and a slowly progressing reversal of ADC changes in the periphery of the ischemic territory, but only to transient and partial improvement in the center. Three hours after initiation of thrombolysis, the tissue volume with ADC values less than 80% of control was 39 +/- 22% as compared to 61 +/- 20% of ipsilateral hemisphere in untreated animals (means +/- SD, P = .03) and the volume of ATP-depleted brain tissue was 25 +/- 31% as compared to 46 +/- 29% in untreated animals. Recovery of ischemic brain injury after thromboembolism is incomplete even when therapy is started as early as 15 minutes after clot embolism. Possible explanations for our findings include downstream displacement of clot material, microembolism of the vascular periphery, and events associated with reperfusion injury.

Adenosine Triphosphate↗
PubMed1997

Improved model of thromboembolic stroke and rt-PA induced reperfusion in the rat.

We report the technical details and validation of an improved rat model for thromboembolic stroke and rt-PA induced reperfusion, which closely resembles clinical embolic stroke. The middle cerebral artery (MCA) was proximally occluded by injection of twelve medium sized (1.5 x 0.35 mm), fibrin-rich autologous blood clots. On inspection, densely packed clot material was found at the ipsilateral MCA origin in all untreated animals. Autoradiographic rCBF measurements showed severe ischemic deficit throughout the ipsilateral MCA territory in untreated animals. The volume in which flow values fell below 30 ml/100 g per min was 54 +/- 14% of the hemispheric volume. In all rt-PA treated animals the proximal MCA was recanalised, and the volume with flow values below 30 ml/100 g per min was reduced to 29 +/- 17%. Histological findings paralleled the spatial spread of the CBF deficit. The rat model presented is well-suited for investigations of the specific pathophysiology of thromboembolic stroke. Furthermore it allows detailed studies of thrombolytically induced reperfusion, beyond the question of successful recanalisation.

Animals↗