101
|
Eckstein AK, Quadbeck B, Tews S, Mann K, Krüger C, Mohr CH, Steuhl KP, Esser J, Gieseler RK. Thyroid associated ophthalmopathy: evidence for CD4(+) gammadelta T cells; de novo differentiation of RFD7(+) macrophages, but not of RFD1(+) dendritic cells; and loss of gammadelta and alphabeta T cell receptor expression. Br J Ophthalmol 2004; 88:803-8. [PMID: 15148216 PMCID: PMC1772193 DOI: 10.1136/bjo.2003.035915] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
AIM To characterise periorbital immune cells (stages, kinetics) in active and inactive thyroid associated ophthalmopathy (A-TAO; I-TAO). METHODS In orbital tissue cryosections of patients with A-TAO (n = 15), I-TAO (n = 11), and healthy controls (n = 14), adipose and fibrovascular areas were evaluated for MHC II(+) cells, CD45(+) total leukocytes, myeloid cells (CD33(+) monocytes; CD14(+) macrophages; mature RFD7(+) macrophages; RFD1(+) dendritic cells (DCs)), and lymphoid cells (CD4(+) T cells; alphabeta and gammadelta T cells; CD20(+) B cells). Results are expressed as medians and 5% confidence intervals. RESULTS In fibrovascular septae, a surge of CD33(+) immigrants clearly correlating with disease activity generated significantly increased (p<0.05) percentages of CD14(+) and RFD7(+) macrophages. Intriguingly, CD4(+) cells were mostly gammadelta T cells, while alphabeta T helper cells were much less frequent. Successful treatment rendering TAO inactive apparently downregulates monocyte influx, macrophage differentiation, and T cell receptor expression. Similar trends were recorded for adipose tissue. Interestingly, RFD1(+) DCs were completely absent from all conditions examined. CONCLUSION A-TAO coincides with periorbital monocyte infiltration and de novo differentiation of macrophages, but not DCs. The authors discuss a novel potential role for inflammatory CD4(+) gammadelta T cells in TAO. Successful treatment apparently downregulates orbital monocyte recruitment and effects functional T cell knockout.
Collapse
|
102
|
Krüger C, Pearson SK, Kodama Y, Vacca Smith A, Bowen WH, Hammarström L. The Effects of Egg-Derived Antibodies to Glucosyltransferases on Dental Caries in Rats. Caries Res 2003; 38:9-14. [PMID: 14684971 DOI: 10.1159/000073914] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2002] [Accepted: 09/09/2003] [Indexed: 11/19/2022] Open
Abstract
The role of Streptococcus mutans in the development of dental caries is well recognized. Important virulence factors include the glucosyltransferases (gtf), essential for production of glucans. We evaluated the anticariogenic effects of orally administered chicken anti-cell-associated (CA) Gtf antibodies in desalivated rats. The animals were infected with S. mutans MT8148R and treated with chicken anti-CA-Gtf egg yolk antibodies (IgY) or nonimmune egg yolk powder. Smooth surface lesions were significantly lower in the anti-CA-Gtf-treated group in comparison to the control groups. Sulcal surface caries was also decreased and of less severity. Our study suggests that chicken anti-CA-Gtf antibodies may have promise as a prophylaxis for high caries risk patients.
Collapse
|
103
|
Rutten T, Krüger C, Melzer M, Stephan UW, Hell R. Discovery of an extended bundle sheath in Ricinus communis L. and its role as a temporal storage compartment for the iron chelator nicotianamine. PLANTA 2003; 217:400-6. [PMID: 14520566 DOI: 10.1007/s00425-003-1010-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2002] [Accepted: 01/09/2003] [Indexed: 05/08/2023]
Abstract
The extended bundle sheath (EBS) is a specialized layer of cells that enhances the lateral transport of photoassimilates within the leaf. This little-known tissue is often considered to be legume-specific. We identified an EBS in cotyledons and leaves of the non-legume Ricinus communis L. By means of cytological and immunological studies and using the localization of the iron-chelator nicotianamine as an established indicator for mass transport, we confirmed its role as a transport tissue and a temporal sink. Observations on cotyledons of Ricinus seedlings further proved that the EBS carries out these tasks from a very early stage of development onwards. This is the first time that information has been obtained on the physiological role of an EBS in a non-legume. Our results support the idea of its widespread occurrence among higher plants.
Collapse
|
104
|
Schnakenberg U, Krüger C, Pfeffer JG, Mokwa W, von Bögel G, Günther R, Schmitz-Rode T. Transponder system for non-invasive measurement of intravascular pressure. BIOMED ENG-BIOMED TE 2003; 47 Suppl 1 Pt 1:191-3. [PMID: 12451814 DOI: 10.1515/bmte.2002.47.s1a.191] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Monitoring of blood pressure and pulse rate offers diagnostical and therapeutical opportunities in hypertension disease and arrhythmia, respectively. This paper presents an intravascular pressure monitoring system consisting of an implantable silicone capsule, which can be placed in an arterial system via a catheter. The capsule contains a pressure sensor and signal conditioning circuits for wireless data and energy transfer using 6.78 MHz transponder technology.
Collapse
|
105
|
Lehnerdt G, Metz KA, Krüger C, Dost P. [A bone-destroying tumor of the maxilla. Reparative giant cell granuloma or brown tumor?]. HNO 2003; 51:239-244. [PMID: 12627253 DOI: 10.1007/s00106-002-0690-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Brown tumors are focal bone lesions caused by an increased osteoclastic activity and fibroblastic proliferation within a primary or more rarely secondary hyperparathyroidism. They are named after their typical brown hemorrhagic stroma with its also typical giant cell formations. We report the case of a 31-year-old pregnant patient with a rapidly growing tumor of her left maxilla whose first symptoms during pregnancy mimicked chronic sinusitis. After swelling of the cheek, diplopia, and recurrent epistaxis appeared, she was referred to our Department for further diagnostics. After CT scan, biopsy was performed under the presumption of a malignant process with the surprising histological result of a reparative giant cell granuloma. At the same time, hyperthyroidism and nodular goiter were diagnosed and further endocrinological examinations were planned. Not until a parathyroid adenoma was diagnosed after urgent operation of the maxillary process (loose molar teeth and displacement of the left bulbus) could the tumor be interpreted and detected within this context of primary hyperparathyroidism as a brown tumor. The brown tumor should be taken into consideration as a rare differential diagnosis of a bone-destroying process of the facial bones. We discuss the clinical signs, diagnostics, and therapy for this case as well as the relevant literature. The reparative giant cell granuloma represents an important differential diagnosis and cannot be distinguished from a brown tumor by histological examination or radiological findings without complete information about the clinical signs and the endocrinological status of the patient.
Collapse
|
106
|
Van Staden CW, Krüger C. Incapacity to give informed consent owing to mental disorder. JOURNAL OF MEDICAL ETHICS 2003; 29:41-43. [PMID: 12569195 PMCID: PMC1733664 DOI: 10.1136/jme.29.1.41] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
What renders some mentally disordered patients incapable of informed consent to medical interventions? It is argued that a patient is incapable of giving informed consent owing to mental disorder, if a mental disorder prevents a patient from understanding what s/he consents to; if a mental disorder prevents a patient from choosing decisively; if a mental disorder prevents a patient from communicating his/her consent; or if a mental disorder prevents a patient from accepting the need for a medical intervention. This paper holds that a patient's capacity to give informed consent should be assessed clinically by using these conditions necessary for informed consent, and should be assessed specifically for each intervention and specifically at the time when the consent has to be given. The paper considers patients' incapacity to give informed consent to treatment, to give informed consent to be examined clinically, and to give informed consent to participate in research.
Collapse
|
107
|
Krüger C, Lahm T, Zugck C, Kell R, Schellberg D, Schweizer MWF, Kübler W, Haass M. Heart rate variability enhances the prognostic value of established parameters in patients with congestive heart failure. ZEITSCHRIFT FUR KARDIOLOGIE 2002; 91:1003-12. [PMID: 12490990 DOI: 10.1007/s00392-002-0868-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
This prospective study evaluated whether heart rate variability (HRV) assessed from Holter ECG has prognostic value in addition to established parameters in patients with congestive heart failure (CHF). The study included 222 patients with CHF due to dilated or ischemic cardiomyopathy (left ventricular ejection fraction LVEF 21+/-1%; mean+/-SEM). During a mean follow-up of 15+/-1 months, 38 (17%) patients died and 45 (20%) were hospitalized due to worsening of CHF. The HRV parameter SDNN (standard deviation of all intervals between normal beats) was significantly lower in non-surviving or hospitalized than in event-free patients (118+/-6 vs 142+/-5 ms), as were LVEF (18+/-1 vs 23+/-1%), and peak oxygen uptake during exercise (peak VO(2)) (12.8+/-0.5 vs 15.6+/-0.5 ml/min/kg). While each of these parameters was a risk predictor in univariate analysis, multivariate analysis revealed that HRV provides both independent and additional prognostic information with respect to the risk 'cardiac mortality or deterioration of CHF'. It is concluded that the determination of HRV enhances the prognostic power given by the most widely used parameters LVEF and peak VO(2) in the prediction of mortality or deterioration of CHF and thus enables to improve risk stratification.
Collapse
|
108
|
Krüger C, Jonas U. Synthesis and pH-Selective Adsorption of Latex Particles onto Photolithographically Patterned Silane Layers. J Colloid Interface Sci 2002; 252:331-8. [PMID: 16290797 DOI: 10.1006/jcis.2002.8492] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2001] [Accepted: 05/20/2002] [Indexed: 11/22/2022]
Abstract
Surface structures of charged latex particles on patterned surface layers were obtained by a colloidal self-assembly process. The laterally patterned silane layers were prepared on silica surfaces by vapor phase and solution deposition of silanes in combination with photolithography. The monodisperse latex particles used in the self-assembly experiments were synthesized by emulsion polymerization to yield poly-n-butylmethacrylate spheres (217 nm diameter) and poly-n-butylacrylate microgels (155 nm). Both particle types possessed a high surface concentration of free carboxylic acid groups as quantified by polyelectrolyte titration under shear flow. Depending on the pH, the particles assembled onto the hydrophobic surface regions (pH 9) or onto the hydrophilic regions (pH 5). Highest selectivity and pattern quality was obtained with permanently positively charged silane layers (quaternary ammonium salts) onto which the negatively charged colloid particles adhered strongly by Coulomb interaction.
Collapse
|
109
|
Jonas U, del Campo A, Krüger C, Glasser G, Boos D. Colloidal assemblies on patterned silane layers. Proc Natl Acad Sci U S A 2002; 99:5034-9. [PMID: 11959954 PMCID: PMC122717 DOI: 10.1073/pnas.082634799] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2001] [Indexed: 11/18/2022] Open
Abstract
The site-selective assembly of colloidal polymer particles onto laterally patterned silane layers was studied as a model system for the object assembly process at mesoscale dimensions. The structured silane monolayers on silicon oxide substrates were fabricated by a combination of liquid- and gas-phase deposition of different trialkoxysilanes with a photolithographic patterning technique. By using this method various types of surface functionalizations such as regions with amino functions next to areas of the bare silica surface or positively charged regions of a quaternary ammonium silane surrounded by a hydrophobic octadecylsilane film could be obtained. Furthermore, a triethoxysilane with a photoprotected amino group was synthesized, which allowed direct photopatterning after monolayer preparation, leading to free NH(2) groups at the irradiated regions. The different silane monolayer patterns were used to study the surface assembly behavior of carboxylated methacrylate particles by optical and scanning electron microscopy. In dependence of the assembly conditions (different surface functionalizations, pH, and drying conditions), a selective preference of the particles for a specific surface type versus others was found. Site-specific colloid adsorption could be observed also on the photosensitive silane layers after local deprotection with light. From the photosensitive silane and positively charged ammonium silane, molecularly mixed monolayers were prepared, which allowed particle adsorption and photoactivation within the same monolayer as shown by fluorescence labeling.
Collapse
|
110
|
Jonas U, Krüger C. The effect of polar, nonpolar, and electrostatic interactions and wetting behavior on the particle assembly at patterned surfaces. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1472-7862(03)00080-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
111
|
Hinderaker SG, Krüger C, Olsen BE, Naman N, Bergsjø P, Olsen OH. Low HIV-seroprevalence in pregnant women in a rural area in Tanzania. Acta Obstet Gynecol Scand 2001; 80:1152-3. [PMID: 11846719 DOI: 10.1034/j.1600-0412.2001.801218.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
112
|
Zugck C, Krüger C, Kell R, Körber S, Schellberg D, Kübler W, Haass M. Risk stratification in middle-aged patients with congestive heart failure: prospective comparison of the Heart Failure Survival Score (HFSS) and a simplified two-variable model. Eur J Heart Fail 2001; 3:577-85. [PMID: 11595606 DOI: 10.1016/s1388-9842(01)00167-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
AIMS The performance of a US-American scoring system (Heart Failure Survival Score, HFSS) was prospectively evaluated in a sample of ambulatory patients with congestive heart failure (CHF). Additionally, it was investigated whether the HFSS might be simplified by assessment of the distance ambulated during a 6-min walk test (6'WT) instead of determination of peak oxygen uptake (peak VO(2)). METHODS AND RESULTS In 208 middle-aged CHF patients (age 54+/-10 years, 82% male, NYHA class 2.3+/-0.7; follow-up 28+/-14 months) the seven variables of the HFSS: CHF aetiology; heart rate; mean arterial pressure; serum sodium concentration; intraventricular conduction time; left ventricular ejection fraction (LVEF); and peak VO(2), were determined. Additionally, a 6'WT was performed. The HFSS allowed discrimination between patients at low, medium and high risk, with mortality rates of 16, 39 and 50%, respectively. However, the prognostic power of the HFSS was not superior to a two-variable model consisting only of LVEF and peak VO(2). The areas under the receiver operating curves (AUC) for prediction of 1-year survival were even higher for the two-variable model (0.84 vs. 0.74, P<0.05). Replacing peak VO(2) with 6'WT resulted in a similar AUC (0.83). CONCLUSION The HFSS continued to predict survival when applied to this patient sample. However, the HFSS was inferior to a two-variable model containing only LVEF and either peak VO(2) or 6'WT. As the 6'WT requires no sophisticated equipment, a simplified two-variable model containing only LVEF and 6'WT may be more widely applicable, and is therefore recommended.
Collapse
|
113
|
Krüger C, Zugck C, Landerer V, Kübler W, Haass M. d,l-sotalol enhances baroreflex sensitivity in conscious rats surviving acute myocardial infarction. Pharmacol Res 2001; 44:13-20. [PMID: 11428905 DOI: 10.1006/phrs.2001.0799] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aim of the present study was to characterize the influence of D,L-sotalol on arterial baroreflex sensitivity (BRS) which is generally considered as an estimate of vagal activity and has prognostic value in patients after myocardial infarction (MI). Conscious rats were studied 3 days after left anterior descending coronary artery ligation (n= 5) or sham-operation (SH, n= 6). BRS was determined by linear regression analysis of the RR-interval (interval between heart beats) and mean arterial pressure changes evoked by i.v. bolus injections of methoxamine (inducing reflex bradycardia, RB) and nitroprusside (inducing reflex tachycardia, RT). In MI-rats heart rate and mean arterial pressure were not significantly different from values in SH-rats, left ventricular end-diastolic pressure was increased and contractility was depressed. The BRS (RB: MI: 0.48 +/- 0.04(*), SH: 0.79 +/- 0.08; RT: MI: 0.41 +/- 0.05(*), SH: 0.86 +/- 0.08 ms mmHg(-1)) ((*)P< 0.05 vs SH) was markedly reduced. d, l -Sotalol (1.5 mg kg(-1)i.v.) reduced heart rate (MI: -11 +/- 3 %(*), SH: -11 +/- 3 %(*)) and mean arterial pressure only moderately [MI: -6 +/- 4 %(n.s.), SH: -7 +/- 2 %(*)], while BRS depression in MI-rats was completely neutralized [RB: MI: 1.08 +/- 0.14(*), SH: 1.19 +/- 0.11(*); RT: MI: 0.84 +/- 0.08(*), SH: 0.88 +/- 0.12 (n.s.) ms mmHg(-1)] ((*)P< 0.05 vs pretreatment). The BRS is reduced in rats early after MI, indicating a depressed reflex vagal activity. Treatment with D,L-sotalol at a dose with little effect on heart rate and mean arterial pressure markedly enhances and, thus, restores BRS in MI-rats. These data suggest that D,L-sotalol has both peripheral and central effects leading to an increase of reflex vagal control of heart rate in rats.
Collapse
|
114
|
|
115
|
Walter P, Schnakenberg U, vom Bögel G, Ruokonen P, Krüger C, Dinslage S, Lüdtke Handjery HC, Richter H, Mokwa W, Diestelhorst M, Krieglstein GK. Development of a completely encapsulated intraocular pressure sensor. Ophthalmic Res 2000; 32:278-84. [PMID: 11015039 DOI: 10.1159/000055626] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A completely encapsulated intraocular pressure (IOP) sensor equipped with telemetric signal and energy transfer is introduced integrated into a silicone disc for implantation into the eye. After implantation into enucleated pig eyes and into rabbit eyes in vivo, the IOP was recorded and compared to established techniques of IOP measurement. Pressure chamber tests showed that the sensor functioned correctly after biocompatible encapsulation in polydimethylsiloxane. In vivo and in vitro tests in rabbit and pig eyes demonstrated that the implanted system worked with the same precision as established techniques for IOP determination. The correlation between the measurements with the implanted device and pneumotonometry in several experiments was between 0.9 and 0.99. This device serves as a functioning model for the realization of a telemetric IOP sensor for integration into an artificial intraocular lens. Such a device will open new perspectives, not only in the management of glaucoma, but also in basic research for mechanisms of glaucoma.
Collapse
|
116
|
Böswald M, Döbig C, Kändler C, Krüger C, Scharf J, Soergel F, Zink S, Guggenbichler JP. Pharmacokinetic and clinical evaluation of serious infections in premature and newborn infants under therapy with imipenem/cilastatin. Infection 2000; 27:299-304. [PMID: 10885853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Efficacy and pharmacokinetic parameters of imipenem/cilastatin (I/C) were investigated in a retrospective evaluation in 104 premature and newborn infants. Patients enrolled in this investigation constituted a particularly high risk group with extreme prematurity, perinatal asphyxia and amnion infection as well as various malformations. In 15 of the 104 infants serum concentrations were measured for drug monitoring and determination of optimal total daily dosage. A total daily dose of 50 mg/kg birth weight for premature and newborn infants divided into two doses led to imipenem peak concentrations of 17.7 mg/l +/- 9.2 mg/l (range: 1.95-38.05) and trough levels were 2.35 mg/l +/-1.02 (range 2.34-10.88) in premature infants. Imipenem peak concentrations of 20.6 +/- 10.8 (range 3.94-32.3) and trough levels of 0.43 +/- 0.17 (range 0.16-0.94) were measured in newborns. The half-life of elimination was 3.3 h and 1.86 h, respectively. Six of the 104 treated patients died, five of them of causes unrelated to infection. Seizures occurred in 8.9% of patients during therapy with I/C compared with 5.8% of a large survey of premature and newborn infants in our intensive care unit (ICU). However, the severity of illness of these two groups cannot be compared. I/C can be expected to constitute effective therapy in premature and newborn infants with serious nosocomial infections even after failure of other broad spectrum antibiotics.
Collapse
|
117
|
Kayser M, Roewer L, Hedman M, Henke L, Henke J, Brauer S, Krüger C, Krawczak M, Nagy M, Dobosz T, Szibor R, de Knijff P, Stoneking M, Sajantila A. Characteristics and frequency of germline mutations at microsatellite loci from the human Y chromosome, as revealed by direct observation in father/son pairs. Am J Hum Genet 2000; 66:1580-8. [PMID: 10762544 PMCID: PMC1378017 DOI: 10.1086/302905] [Citation(s) in RCA: 250] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/1999] [Accepted: 02/23/2000] [Indexed: 11/03/2022] Open
Abstract
A number of applications of analysis of human Y-chromosome microsatellite loci to human evolution and forensic science require reliable estimates of the mutation rate and knowledge of the mutational mechanism. We therefore screened a total of 4,999 meioses from father/son pairs with confirmed paternity (probability >/=99. 9%) at 15 Y-chromosomal microsatellite loci and identified 14 mutations. The locus-specific mutation-rate estimates were 0-8. 58x10-3, and the average mutation rate estimates were 3.17x10-3 (95% confidence interval [CI] 1.89-4.94x10-3) across 8 tetranucleotide microsatellites and 2.80x10-3 (95% CI 1.72-4.27x10-3) across all 15 Y-chromosomal microsatellites studied. Our data show a mutational bias toward length increase, on the basis of observation of more repeat gains than losses (10:4). The data are in almost complete agreement with the stepwise-mutation model, with 13 single-repeat changes and 1 double-repeat change. Sequence analysis revealed that all mutations occurred in uninterrupted homogenous arrays of >/=11 repeats. We conclude that mutation rates and characteristics of human Y-chromosomal microsatellites are consistent with those of autosomal microsatellites. This indicates that the general mutational mechanism of microsatellites is independent of recombination.
Collapse
|
118
|
Zugck C, Krüger C, Dürr S, Gerber SH, Haunstetter A, Hornig K, Kübler W, Haass M. Is the 6-minute walk test a reliable substitute for peak oxygen uptake in patients with dilated cardiomyopathy? Eur Heart J 2000; 21:540-9. [PMID: 10775009 DOI: 10.1053/euhj.1999.1861] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
AIMS The 6-min walk test may serve as a more simple clinical tool to assess functional capacity in congestive heart failure than determination of peak oxygen uptake by cardiopulmonary exercise testing. The purpose of the study was to prospectively examine whether the distance ambulated during a 6-min walk test (i) correlates with peak oxygen uptake, (ii) allows peak oxygen uptake to be predicted, and (iii) provides prognostic information similar to peak oxygen uptake in patients with dilated cardiomyopathy and left ventricular ejection fraction < or = 35%. METHODS AND RESULTS In 113 patients (age: 54+/-12 years, NYHA: 2.2+/-0.8) with dilated cardiomyopathy (left ventricular ejection fraction 19+/-7%) a 6-min walk test and cardiopulmonary exercise testing were performed. The 6-min walk test and peak oxygen uptake were closely correlated at the initial visit (r=0.68, n=113), as well as after 263+/-114 (r=0.71, n=28) and 381+/-170 days (r=0.74, n=14). During serial exercise testing the 6-min walk test allowed peak oxygen uptake to be reliably predicted (r=0.76 between calculated and real peak oxygen uptake). After 528+/-234 days, 42 patients were hospitalized due to worsening heart failure and/or died from cardiovascular causes. Compared to clinically stable patients, these 42 patients walked a shorter distance (423+/-104 vs 501+/-95 m, P<0.001) and had a lower peak oxygen uptake (12.7+/-4.0 vs 17.4 + 5.6 ml x min(-1) x kg(-1), P<0.001). By univariate analysis the 6-min walk test outperformed other prognostic parameters such as left ventricular ejection fraction, cardiac index and plasma norepinephrine concentration and conferred a prognostic power similar to peak oxygen uptake. This predictive value could be further improved in a multivariate model, by combining the 6-min walk test with independent variables, such as left ventricular ejection fraction or cardiac index. CONCLUSION The 6-min walk test correlated with peak oxygen uptake when tested serially over the course of the disease. Although both tests define two distinct domains of functional capacity, the 6-min walk test provides prognostic information very similar to peak oxygen uptake in congestive heart failure patients with dilated cardiomyopathy.
Collapse
|
119
|
Westermann J, Thiemann F, Gerstner L, Tatzber F, Kozák I, Bertsch T, Krüger C. Evaluation of a new simple and rapid enzyme-linked immunosorbent assay kit for neopterin determination. Clin Chem Lab Med 2000; 38:345-53. [PMID: 10928656 DOI: 10.1515/cclm.2000.050] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A new commercially available enzyme-linked immunosorbent assay (ELISA) kit has been evaluated for the measurement of neopterin concentrations in serum, plasma and urine. This competitive ELISA is technically simple, requires only small sample volume and is rapid to perform. The assay procedure consists of sequential 1.5 h and 10 min room temperature incubation steps. The ELISA is accurate, sensitive, specific, and precise. Linear regression analysis of neopterin concentrations measured with the new ELISA and with an established method yielded a highly significant correlation (r = 0.99). The new assay is applicable to ELISA workstations, thus enabling determination of neopterin in large series of samples. The neopterin ELISA kit has been used in routine laboratory testing of blood donations in a blood bank.
Collapse
|
120
|
Krüger C, Landerer V, Zugck C, Ehmke H, Kübler W, Haass M. The bradycardic agent zatebradine enhances baroreflex sensitivity and heart rate variability in rats early after myocardial infarction. Cardiovasc Res 2000; 45:900-12. [PMID: 10728416 DOI: 10.1016/s0008-6363(99)00405-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
OBJECTIVE The bradycardic agent zatebradine (UL-FS 49) reduces heart rate without negative inotropic or proarrhythmic effects. The aim was to experimentally characterize the influence of zatebradine on arterial baroreflex sensitivity (BRS) and heart rate variability (HRV) which are generally considered as estimates of vagal activity and have prognostic value in patients after myocardial infarction (MI). METHODS Conscious rats were studied 3 days after left coronary artery ligation or sham-operation (SH). BRS was determined by linear regression analysis of RR-interval and mean arterial pressure changes evoked by intravenous (i.v.) injections of methoxamine and nitroprusside. HRV at rest was calculated from high-resolution electrocardiogram-recordings. RESULTS In MI-rats heart rate was similar to SH-rats, mean arterial pressure was lower and both BRS and HRV were markedly reduced. Zatebradine (0.5 mg/kg i.v.) reduced heart rate in MI-rats from 400 +/- 15 to 350 +/- 19 and in SH-rats from 390 +/- 19 to 324 +/- 6 beats/min without changing mean arterial pressure. Both BRS and HRV were restored in MI- and further increased in SH-rats by the drug. Effects of 0.05, 0.5 and 5 mg/kg zatebradine revealed a dose-dependency of heart rate reduction. The lowest dose enhanced reflex bradycardia despite little effect on heart rate and lack of effect on both reflex tachycardia and HRV. CONCLUSIONS Both BRS and HRV are reduced in rats early after MI, indicating a depressed reflex and tonic vagal activity. Treatment with zatebradine enhances both BRS and HRV. These data suggest that the drug has both peripheral and central effects, leading to an increase of vagal control of heart rate.
Collapse
|
121
|
Winnik MA, Pinenq P, Krüger C, Zhang J, Yaneff PV. Crosslinking vs. interdiffusion rates in melamine-formaldehyde cured latex coatings: A model for waterborne automotive basecoat. ACTA ACUST UNITED AC 1999. [DOI: 10.1007/bf02697910] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
122
|
Bruckmann J, Krüger C, Lehmann CW, Leitner W, Rust J, Six C. Ethylenebis(phosphonic acid). Acta Crystallogr C 1999. [DOI: 10.1107/s0108270198016448] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
123
|
Gerber SH, Heyer C, Krüger C, Hagl S, Kübler W, Haass M. Influence of Bretschneider's cardioplegia on norepinephrine release from isolated perfused guinea-pig hearts. J Mol Cell Cardiol 1999; 31:89-99. [PMID: 10072718 DOI: 10.1006/jmcc.1998.0849] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
It was the aim of the present study to investigate the influence of Bretschneider's cardioplegia on norepinephrine (NE) release [determined by high pressure liquid chromatography (HPLC) and electrochemical detection] in isolated perfused guinea-pig hearts. The following resulted were noted. (1) Calcium-dependent exocytotic NE release evoked by electrical field stimulation (12 Hz, 1 min) was completely suppressed after only 3 min of normothermic (37.5 degrees C) Bretschneider's cardioplegia. (2) Stop-flow ischemia is associated with a substantial calcium-independent, non-exocytotic NE release, which is regarded as a sodium-dependent carrier-mediated process. Accordingly, it is inhibited by blockers of the sodium/proton-exchanger (e.g. amiloride) and the neuronal uptake1-carrier (e.g. desipramine). Compared with stop-flow ischemia alone, cardioplegia with 3 min of Bretschneider's histidine-tryptophan-ketoglutarate (HTK)-solution preceding stop-flow enhanced NE release at all stop-flow durations (10-90 min) investigated (e.g. after 30 min of normothermic Bretschneider's cardioplegia: 1070+/-41 pmol/g, n = 45, v stop-flow alone: 764+/-48 pmol/g, n = 27, P<0.05). The NE concentrations determined in the cardiac effluent upon reperfusion followed a typical first order kinetic indicating that the transmitter release had already occurred during stop-flow. Hypothermia reduced NE release in a temperature-dependent manner down to intramyocardial temperatures of 2 7.5 degrees C. NE release evoked by Bretschneider's cardioplegia still exceeded that induced by stop-flow ischemia alone by up to 60%. The NE release evoked by Bretschneider's cardioplegia and stop-flow ischemia was calcium-independent. However, it was significantly reduced by desipramine and amiloride, but both agents had a more pronounced inhibitory effect on NE release evoked by stop-flow ischemia alone. (3) This difference may be due to an intrinsic effect of Bretschneider's HTK-solution, as continuous administration of normothermic Bretschneider's HTK-solution induced a substantial NE release which was neither calcium-dependent nor inhibited by blockade of either uptake1 or sodium/proton-exchange. It is concluded that Bretschneider's cardioplegia is not neuroprotective, as it even augments the stop-flow ischemia-induced nonexocytotic NE release.
Collapse
|
124
|
Zenker M, Klinge J, Krüger C, Singer H, Scharf J. Severe pulmonary hypertension in a neonate caused by premature closure of the ductus arteriosus following maternal treatment with diclofenac: a case report. J Perinat Med 1998; 26:231-4. [PMID: 9773385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The administration of non-steroidal antiinflammatory drugs (NSAID) has occasionally been related to fetal and neonatal cardiopulmonary, gastrointestinal, cerebral and renal complications. This report describes a term newborn with severe persistent pulmonary hypertension due to premature closure of the ductus arteriosus following a 5 day maternal treatment with diclofenac two weeks before delivery. Pulmonary hypertension only responded to unusually high doses of inhaled NO. The treatment was necessary for 22 days suggesting structural alteration of pulmonary vasculature. The child recovered, but tricuspid regurgitation persisted, presumably because of irreversible ischemic damage of one papillary muscle. This is the first reported case of persistent pulmonary hypertension of the newborn (PPHN) in association with maternal diclofenac treatment and represents a most severe form of PPHN induced by NSAID.
Collapse
|
125
|
Schneider JJ, Hagen J, Heinemann O, Krüger C, de Biani F, Zanello P. Synthesis, structure, spectroelectrochemical and theoretical investigations of Formation of a cobalt complexed stannacycle via a mixed alkyne-stannylene cycloaddition reaction. Inorganica Chim Acta 1998. [DOI: 10.1016/s0020-1693(98)00141-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|