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M Becker

Publications and source records attributed to M Becker.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Reconstruction of defects at the neuromuscular junction].

Loss of muscle tissue at the area of the neuromuscular junction after tumor resection or after trauma precludes the reconstruction with conventional nerve grafts, because the distal nerve stump is absent. For these cases, we recommend direct insertion of the nerve grafts into the muscle. We describe a standardized technique, which has been performed in 19 patients and led to a mean motor recovery of grade M4 after Highet. The key procedure of this technique is the interfascicular dissection of the nerve grafts, which allows a wide distribution of the grafts into the muscle tissue.

Adult↗
PubMed2003

[Intraoperative histological sections in obstetric brachial plexus lesions--comparison of macroscopic appearance, HE staining and toluidine blue staining].

In brachial plexus lesions and their revision, evaluation of nerve stumps is very important for the reconstructive strategy. We intraoperatively perform cryostat sections, Haematoxilin-Eosin (HE) stained, and compare the clinical appearance of the nerves to the microscopic results. Toluidine blue staining is later used to validate the structural details. Intraneural fibrosis can be traced safely with both staining methods, in root avulsions a histology is helpful, too. For more proximal, intraforaminal lesions semithin section stained with toluidine-blue are less informative than are HE-stained cryostat sections. In these lesions the clinical control by electrical stimulation and evoked potentials is superior.

Adult↗
PubMed2003

Sustainable stormwater concepts as an essential instrument for river basin management.

The Emscher system, with its open wastewater drains, has been undergoing reconstruction since 1990. The watercourses, now relieved of the burden of wastewater, are being reconstituted as close to nature as possible. An important precondition, for which naturally orientated rainwater management concepts must be implemented in this densely populated region, is a homogenized run-off. Emschergenossenschaft has in recent years provided financial and conceptual support for the implementation of such changes. Present-day experience demonstrates that disconnection of 10% of impervious areas within the next fifteen years is a realistic target and consequently the aim for next year's work. As detailed studies using precipitation run-off models document, this will decisively improve the flood and minimum water situations of the small tributary watercourses in particular, which is important regarding the aims of the EU WFD.

Conservation of Natural Resources↗
PubMed2002

Sensitive PCR method for the detection and real-time quantification of human cells in xenotransplantation systems.

The sensitive detection of human cells in immunodeficient rodents is a prerequisite for the monitoring of micrometastasis of solid tumours, dissemination of leukaemic cells, or engraftment of haematological cells. We developed a universally applicable polymerase chain reaction method for the detection of a human-specific 850-bp fragment of the alpha-satellite DNA on human chromosome 17. The method allows the detection of one human cell in 10(6) murine cells and could be established as both, a conventional DNA polymerase chain reaction-assay for routine screening, and a quantitative real-time polymerase chain reaction-assay using TaqMan-methodology. It was applied to the following xenotransplantation systems in SCID and NOD/SCID mice: (1) In a limiting dilution assay, cells of the MDA-MB 435 breast carcinoma were injected into the mammary fat pad of NOD/SCID mice. It could be shown that 10 cells mouse(-1) were sufficient to induce a positive polymerase chain reaction signal in liver and lung tissue 30 days after transplantation as an indicator for micrometastasis. At this time a palpable tumour was not yet detectable in the mammary fat pad region. (2) Cells of a newly established human acute lymphatic leukaemia were administered intraperitoneally to SCID mice. These cells apparently disseminated and were detectable as early as day 50 in the peripheral blood of living mice, while the leukaemia manifestation was delayed by day 140. (3) In a transplantation experiment using mature human lymphocytes we wanted to standardise conditions for a successful survival of these cells in NOD/SCID mice. It was established that at least 5 x 10(7) cells given intravenously were necessary and that the mice had to be conditioned by 2 Gy body irradiation to get positive polymerase chain reaction bands in several organs. (4) Engraftment studies with blood stem cells originating from cytapheresis samples of tumour patients or from cord blood were undertaken in NOD/SCID mice in order to define conditions of successful engraftment and to use this model for further optimisation strategies. The polymerase chain reaction method presented allowed a reliable prediction of positive engraftment and agreed well with the results of immunohistochemical or FACS analysis. All together, the polymerase chain reaction method developed allows a sensitive and reliable detection of low numbers of human cells in immunodeficient hosts. In combination with real-time (TaqMan) technique it allows an exact quantification of human cells. As this method can be performed with accessible material of living animals, follow up studies for the monitoring of therapeutic interventions are possible in which the survival time of mice as evaluation criteria can be omitted.

Animals↗
PubMed2002

Alpha1-antitrypsin genotypes in patients with chronic pancreatitis.

BACKGROUND: An association between alpha1-antitrypsin deficiency and chronic pancreatitis (CP) has been reported in several case reports and two systematic studies. However, conflicting results have been shown in other studies of patients with CP. All previous studies were performed by phenotyping or by measurement of serum concentrations of alpha1-antitrypsin. The aim of this study was to investigate the relationship between alpha1-antitrypsin deficiency and CP by genetic analysis. METHODS: Ninety-six unrelated children and adolescents with idiopathic or hereditary CP and 185 healthy controls were enrolled. DNA was extracted from peripheral blood leukocytes and the exons 5 and 7 of the alpha1-antitrypsin gene were amplified by polymerase chain reaction using mutagenic forward primers introducing a Taq I restriction site. Genotyping of the S allele and the Z allele was performed by restriction fragment length polymorphism analysis using Taq I. RESULTS: Seven out of 96 patients (7.3%) with CP were heterozygous for an alpha1-antitrypsin deficiency allele (4 for the S allele and 3 for the Z allele). No patient was homozygous or compound heterozygous for these alleles. Twenty out of 185 control individuals (10.8%) were heterozygous for the S or Z allele (PiS: 12 controls; PiZ: 8 controls). No significant differences were found between the allele frequency in patients and the control individuals (P > 0.1). CONCLUSIONS: Alpha1-antitrypsin deficiency is not related to the pathogenesis of idiopathic or hereditary CP.

Adolescent↗
PubMed2002

Sustainable rainwater management in the Emscher river catchment area.

The wastewater management system of the Emscher region is currently being radically restructured. The receiving waters currently surviving as open sewers are to be freed of their wastewater burden and reconstituted to a state as natural as possible, while the wastewater is to be routed underground to the treatment plants. Great importance is attached to the most natural possible rainwater management, in order to buffer extreme run-off situations in the watercourses and to minimize the costs for residential-area water management engineering. Rethinking, which in many cases percolates through only slowly, is necessary in many respects for this purpose. A contest has been set up in the Emscher catchment area in order to accelerate this in the existing residential areas. Seepage, decentralized retention, disconnection and discharge into bodies of water and watercourses have been financially supported. The results are presented and the further procedure deriving from them discussed.

Conservation of Natural Resources↗
PubMed2002

Inflammatory aneurysms of infra-renal abdominal aorta. A case-control study.

BACKGROUND: A case-control study was conducted to identify significant differences in risk factors, clinical presentation, treatment and prognosis between patients with inflammatory aortic aneurysms (group 1) and atherosclerotic abdominal aneurysms (group 2 - controls). METHODS: Thirty patients with inflammatory aneurysm were repaired at our institution in a 14-year period and were matched to 60 controls by date of surgery. RESULTS: Both groups presented similar characteristics concerning age, gender, risk factors to atherosclerosis and ischemic heart disease. Patients with inflammatory aneurysms presented abdominal pain significantly more than controls (80 versus 41.7%; p=0,001). Erythrocyte sedimentation rate was significantly high in group 1 as compared to group 2 (26 versus 5%; p=0,005). The aneurysm size was significantly greater in group 1 (8 versus 6.4 cm; p=0,01). The surgical technique required was similar in both groups, but the aortic clamping time and the mean blood reposition were higher in group 1 (49.5 versus 41 min; p=0,01 and 1508 versus 1034 ml; p=0,013). Intraoperative injury to adjacent organs was significantly greater in group 1 (10 versus 0%; p=0,034). The mortality rate was neither statistically different in the early postoperative setting (10 versus 1.67%) nor in the 5-year survival rate (67 versus 62%; p>0.05) for groups 1 and 2, respectively. CONCLUSION: This study showed no differences concerning inflammatory aneurysms in terms of risk factors, treatment required and prognosis. Inflammatory aneurysms tend to present with more symptoms, high erythrocyte sedimentation rate, greater size and retroperitoneal inflammatory reaction than usual aneurysms, making the surgical procedure more difficult.

Aged↗
PubMed2001

[Transcatheter closure of atrial septal defects in adults. Practicality and safety of four different closure systems used in 102 patients].

BACKGROUND AND OBJECTIVE: Surgical closure of secundum atrial septal defect (ASD) or patent foramen ovale (PFO) is a procedure with few complications. But this surgical intervention can nowadays be avoided by transcatheter insertion of occluding devices. Such interventional methods must be judged against the results of surgical procedures. This report from one center presents the practicability and safety of different transcatheter occluder systems. PATIENTS AND METHODS: Transcatheter occlusion was undertaken in 102 patients (40 females, 62 males, aged between 17 and 76 years [median age 45]) with either an ASD (41pts.) or a PFO (60 pts.) or with both, in one patient. Four different systems were used: ASDOS (for ASD and PFO), PFO-STAR (for PFO), Amplatzer Septal Occluder (for ASD) or Amplatzer PFO Occluder (for PFO). Follow-up, including transoesophageal echocardiography took place 48 hours, 4 weeks, 6 months and 1 year after the interventional occluder placement. RESULTS: An occluder was successfully placed in the ASD or PFO in 99 of the 102 patients. In three patients the occluder ( ASDOS ASD) could not be correctly ancchored in the defect. In two other patients the same device was subsequently removed surgically because of mispositioning or a large resiudal shunt. Occluder-associated problems were: mild (41%) or extensive (11%) thrombus formation on the occluder without early embolization, residual shunt at one year (ASD 16%, PFO 29%); minor displacement (10%) or broken umbrella strut (6%) of no clinical relevance. One patient required emergency surgical intervention on the day of the transcatheter placement (PFO-STAR) because of pricardial tamponade. Primary complete occlusion was achieved in 71%. There was no case of cerebral emboli. CONCLUSION: Transcatheter occlusion of ASD and/or PFO is a reliable and safe procedure. Regarding peri- and/or postinterventional complications, primary results and practicability, the Amplatzer septal occluder and Amplatzer PFO occluder are particularly advantageous.

Adolescent↗
PubMed2001

Steroid hormone receptor-mediated histone deacetylation and transcription at the mouse mammary tumor virus promoter.

Acetylation of lysines in histones H3 and H4 N-terminal tails is associated with transcriptional activation and deacetylation with repression. Our studies with the mouse mammary tumor virus (MMTV) promoter in chromatin show significant levels of acetylation at promoter proximal and distal regions prior to transactivation. Upon activation with glucocorticoids or progestins, promoter proximal histones become deacetylated within the region of inducible nuclease hypersensitivity. The deacetylation lags behind the initiation of transcription, indicating a role in post-activation regulation. Our results indicate a novel mechanism by which target promoters are regulated by steroid receptors and chromatin modification machinery.

Adenocarcinoma↗
PubMed2001

Copper(I) complexes, copper(I)/O(2) reactivity, and copper(II) complex adducts, with a series of tetradentate tripyridylalkylamine tripodal ligands.

Copper(I) and copper(II) complexes possessing a series of related ligands with pyridyl-containing donors have been investigated. The ligands are tris(2-pyridylmethyl)amine (tmpa), bis[(2-pyridyl)methyl]-2-(2-pyridyl)ethylamine (pmea), bis[2-(2-pyridyl)ethyl]-(2-pyridyl)methylamine (pmap), and tris[2-(2-pyridyl)ethyl]amine (tepa). The crystal structures of the protonated ligand H(tepa)ClO(4), the copper(I) complexes [Cu(pmea)]PF(6) (1b-PF(6)), [Cu(pmap)]PF(6) (1c-PF(6)), and copper(II) complexes [Cu(pmea)Cl]ClO(4).H(2)O (2b-ClO(4).H(2)O), [Cu(pmap)Cl]ClO(4).H(2)O (2c-ClO(4).H(2)O), [Cu(pmap)Cl]ClO(4) (2c-ClO(4)), and [Cu(pmea)F](2)(PF(6))(2) (3b-PF(6)) were determined. Crystal data: H(tepa)ClO(4), formula C(21)H(25)ClN(4)O(4), triclinic space group P1, Z = 2, a = 10.386(2) A, b = 10.723(2) A, c = 11.663(2) A, alpha = 108.77(3) degrees, beta = 113.81(3) degrees, gamma = 90.39(3) degrees; 1b-PF(6), formula C(19)H(20)CuF(6)N(4)P, orthorhombic space group Pbca, Z = 8, a = 14.413(3) A, b = 16.043(3) A, c = 18.288(4) A, alpha = beta = gamma = 90 degrees; (1c-PF(6)), formula C(20)H(22)CuF(6)N(4)P, orthorhombic space group Pbca, Z = 8, a = 13.306(3) A, b = 16.936(3) A, c = 19.163(4) A, alpha = beta = gamma = 90 degrees; 2b-ClO(4).H(2)O, formula C(19)H(22)Cl(2)CuN(4)O(5), triclinic space group P1, Z = 4, a = 11.967(2) A, b = 12.445(3) A, c = 15.668(3) A, alpha = 84.65(3) degrees, beta = 68.57(3) degrees, gamma = 87.33(3) degrees; 2c-ClO(4).H(2)O, formula C(20)H(24)Cl(2)CuN(4)O(5), monoclinic space group P2(1)/c, Z = 4, a = 11.2927(5) A, b = 13.2389(4) A, c = 15.0939(8) A, alpha = gamma = 90 degrees, beta = 97.397(2) degrees; 2c-ClO(4), formula C(20)H(22)Cl(2)CuN(4)O(4), monoclinic space group P2(1)/c, Z = 4, a = 8.7682(4) A, b = 18.4968(10) A, c = 13.2575(8) A, alpha = gamma = 90 degrees, beta = 94.219(4) degrees; 3b-PF(6), formula [C(19)H(20)CuF(7)N(4)P](2), monoclinic space group P2(1)/n, Z = 2, a = 11.620(5) A, b = 12.752(5) A, c = 15.424(6) A, alpha = gamma = 90 degrees, beta = 109.56(3) degrees. The oxidation of the copper(I) complexes with dioxygen was studied. [Cu(tmpa)(CH(3)CN)](+) (1a) reacts with dioxygen to form a dinuclear peroxo complex that is stable at low temperatures. In contrast, only a very labile peroxo complex was observed spectroscopically when 1b was reacted with dioxygen at low temperatures using stopped-flow kinetic techniques. No dioxygen adduct was detected spectroscopically during the oxidation of 1c, and 1d was found to be unreactive toward dioxygen. Reaction of dioxygen with 1a-PF(6), 1b-PF(6), and 1c-PF(6) at ambient temperatures leads to fluoride-bridged dinuclear copper(II) complexes as products. All copper(II) complexes were characterized by UV-vis, EPR, and electrochemical measurements. The results manifest the dramatic effects of ligand variations and particularly chelate ring size on structure and reactivity.

Chelating Agents↗
PubMed2001

Heterogeneity of proteinkinase C activity and PKC-zeta expression in clinical breast carcinomas.

Proteinkinase C (PKC) is involved in carcinogenesis, proliferation, and metastatic spread of breast cancer. New anticancer strategies have been developed with PKC as a potential target for therapeutic intervention. However, most of the encouraging preliminary data were observed in breast cancer cell lines only. Insignificant information is available concerning clinical breast cancer cells. Our aim was to investigate the involvement of PKC in clinical breast carcinoma cells. To this end, we set up short-term cultures (3 days) of native tumor cells derived from 12 patients with advanced breast cancer. Addition of commonly used antineoplastics, including both single agents and combinations (tamoxifen, Adriamycin, paclitaxel, Adriamycin plus paclitaxel, epirubicin plus 4-OOH-cyclophosphamide, mitoxantrone, mitoxantrone plus vinorelbin, vinorelbin), simulated the clinical situation. In relation to each control we determined total PKC activity and quantified the PKC-zeta isoform. In 6 patients, no obvious alteration of PKC activities was detected. In the remainder, either inhibition or augmentation of PKC activity in the presence of cytostatics was detected. However, no tendency could be observed concerning the influence of the therapeutics on PKC activity. PKC-zeta expression was much more heterogeneous than activity assays. Although anticancer drugs influenced PKC-zeta expression, the results showed no uniformity with regard to PKC-zeta expression. Moreover, PKC-zeta expression did not correlate with total PKC activity, indicating a differential expression of different PKC isoenzymes. Therefore, we conclude that both PKC activity and PKC-zeta expression differ individually. More data concerning this topic are necessary prior to offering a clinically useful PKC-tailored regimen.

Adult↗
PubMed2001

[Therapy of soft tissue trauma in the acute phase of severe hand injuries].

INTRODUCTION: Complex hand injuries are characterized by a combination of soft tissue injury and additional trauma to functional structures such as nerves, bones, tendons, vessels and joints. A good functional result requires the reconstruction of the injured structures and early mobilisation. Good vascularized soft tissue and stable osteosyntheses are the major prerequisites to avoid infections and to allow early mobilisation. The optimal timing for soft tissue reconstruction remains controversial with respect to the incidence of infections. METHODS: We have evaluated retrospectively our series of complex hand injuries addressing the question whether a delay of soft tissue coverage for up to 72 hours causes significant increase of infection rates. RESULTS: 48 patients were treated with complex injuries of the hand within a three year period between December 1998 and December 2000. The lowest incidence of infections occurred in the group, where soft tissue coverage was completed as an emergency procedure. DISCUSSION: Ideally primary reconstruction of complex hand injuries should be strived for to minimize scar formation as a result of secondary operations and further immobilisation periods. This includes, if necessary, free tissue transfer. Exceptions are situations where the vitality of soft remains uncertain. In these cases, definitive surgery is delayed for a maximum period of 72 hours.

Acute Disease↗
PubMed2001

[Angle- and rotation-stable internal fixation of proximal humerus fractures with the humerus fixator plate. Early clinical experience with a newly developed implant].

INTRODUCTION: The Humerus Fixator Plate is presented as a new implant for angle- and rotation-stable internal fixation for the operative treatment of proximal humerus fractures at the surgical neck. METHODS: In an ongoing two-centre study, 47 patients were treated with the new implant. To date, 31 patients had clinical and radiological postoperative follow-up examinations with a mean interval of 10 months (range: 6-14 months). RESULTS: In 46 patients (97.9%), complete angle and rotational stability was achieved without limiting the range of motion or requiring immobilization. Good pain relief was obtained in 43 patients (91.5 %), and 3 patients (6.4%) showed moderate pain relief following surgery. There was one implant failure. Utilizing the Constant-Raw score (without any correction factors), a mean result of 82.8 points (range: 46-100 points) was ascertained. The majority of the patients (87.1%) achieved "excellent" or "good" clinical results. X-ray analysis revealed no non-union nor humerus head necrosis. In 4 cases (12.9%), protrusion of a humerus head screw was observed which mandated removal of the implant. CONCLUSION: The first clinical investigations of the novel Humerus Fixator Plate are encouraging and provide essential advances in the treatment of unstable proximal humerus fractures.

Adult↗
PubMed2001

[Diode laser cyclophotocoagulation as the primary surgical intervention in glaucoma].

BACKGROUND: Diode laser cyclophotocoagulation is widely accepted as the therapy of choice in severe glaucoma cases. It is especially performed after failure of other kinds of treatment. We wanted to know whether it is also suitable as a primary surgical procedure after failure of medical treatment. PATIENTS AND METHODS: We retrospectively evaluated the charts of patients scheduled for cyclophotocoagulation as a primary surgical treatment between February 1997 and May 1998. Usually 15 burns (2000 mW, 2.5 s) were applied per treatment session. The mean age was 75.5 +/- 7.4 years (range: 63-86). The mean follow-up was 17.5 months (range: 6-32). RESULTS: Altogether 25 eyes of 20 patients could be included in the study. There was a mean reduction of the intraocular pressure from 29.9 mmHg preoperatively to 17.4 mmHg postoperatively = 41.6%. In three cases (12%) repeated treatment was necessary. No severe complications such as endophthalmitis or phthisis bulbi were observed. No acute postoperative elevation of intraocular pressure > or = 40 mmHg occurred. Visual acuity remained stable during the follow-up in all eyes with a preoperative measurement of 20/60. DISCUSSION: Diode laser cyclophotocoagulation is suitable as a primary surgical procedure. We mostly perform it instead of filtering procedures when the patient refuses the filtering operation or when the patient is not able to visit an ophthalmologist for regular aftercare.

Aged↗
PubMed2001

Incidence of T wave alternation after acute myocardial infarction and correlation with other prognostic parameters: results of a prospective study.

Tachycardia induced alternation of the T wave (TWA) has been associated with arrhythmia morbidity in mixed patient populations. However, less is known concerning the general incidence of TWA and its usefulness in risk stratification early after acute myocardial infarction (MI). TWA was prospectively and systematically assessed in 140 consecutive patients 15 +/- 6 days after acute MI and prior to discharge. Results of TWA measurements were compared to other noninvasive risk markers, LV function, and coronary angiography. Sustained TWA was present at rest or inducible during exercise in 27% of patients. The patient-specific heart rate for the onset of TWA was 98 +/- 9 beats/min. After multivariate analysis, TWA correlated with age (P = 0.02) and LV function (P = 0.002) and occurred more often in patients after nonanterior MI (P = 0.03). Acute results of Holter monitoring, late potentials by signal-averaged ECG, and heart rate variability were unrelated to the TWA status. During follow-up (451 +/- 210 days) two major arrhythmic events occurred. The incidence of TWA early after MI is about 25%. TWA is related to age and LV function but not to other common arrhythmia markers. Although TWA does not appear to be related to excessive cardiac morbidity, evaluation of the prognostic significance of TWA requires further study.

Aged↗