Biomedical subjects

H Lill

Publications and source records attributed to H Lill.

At least 19 recordsLinked to original sources

PubMed2003

[Tibial plateau fracture--biodegradable bonecement-augmentation].

Between October 1996 and January 1999,29 patients (f:16,m:13,age: 22-86) with fractures of the lateral tibial plateau were operated on arthroscopic,fluoroscopic control or were treated with open reduction and internal fixation. 15 of them were retrospective and 14 prospective analysed. The metaphyseal defect after elevation of the depressed fragment was augmented in 11 cases with autologous spongeous bone grafting,in 9 cases with biodegradable bone cement (Norian SRS). Augmentation was unnecessary in 9 cases. The results according to the Lysholm score and the radiological results were good or excellent. Concerning the kind of augmentation no difference was noted. In the Norian SRS-group the duration of postoperative treatment was shorter than in the other group. The duration of partial weight bearing was shorter too. The results of the present study suggest that an injectable calcium phosphate cement may be a competent material for augmentation in lateral tibial plateau fractures because of the application form and the initial high mechanical stability.

Adult↗

PubMed2002

[Endoscopically assisted minimally invasive reconstruction of the anterior thoracolumbar spine in prone position].

Irrespective of an anterior open or endoscopic approach, the combined postero-anterior instrumentation of thoracolumbar fractures requires time consuming intraoperative maneuvers changing the patients position from prone to lateral.A standardised anterior endoscopically assisted approach for the segments Th4 to L4 is described, allowing the patient to remain in prone position, using a 4-5cm incision combined with a retractor system. The approach to the anterior spine in prone position is feasible by using a self holding retractor system for the region from Th4 to L4. Time of anaesthesia for the one stage combined procedure can be reduced by about 40 min, when changing the position of the patient is no longer necessary. The minimal incision in combination with the retractor system allows mainly the use of conventional instruments and implants, which provides reasonable lower costs. The advantages of the open and the endoscopical technique are combined. The main advantage of the prone position is the opportunity to access the anterior and posterior spine simultaneously, which is extremely helpful in reduction maneuvers.

Adult↗

PubMed2002

[Age- and gender-related distribution of bone mineral density and mechanical properties of the proximal humerus].

PURPOSE: To evaluate age- and gender-related mechanical properties and bone mineral density (BMD) of the proximal humerus at different levels and regions. MATERIALS AND METHODS: Mechanical indentation testing, DXA, QCT, pQCT and the radiogrammetry (Cortical Index, CI) were carried out in 70 freshly harvested humeri from 46 human cadavers (23 females, 23-males; median age 70.5 years). RESULTS: In the female group, a high correlation between age and BMD was found (rho = 0.62 to -0.70, p < 0.01) with statistically significant differences between specimens of patients 69 years or younger, and 70 years or older (p < 0.05). In the group of female specimens of age 70 years or older, BMD values were found to be significantly lower compared to their male counterparts (p < 0.05). Regardless of the specimen's age, the highest BMD and bone strength were found in the proximal aspect and in the medial and dorsal regions of the proximal humerus. CONCLUSION: These findings provide an insight into the fracture mechanism of the proximal humerus and should be the basis for designing structure-oriented implants with improved implant-bone stability in osteoporotic patients.

Absorptiometry, Photon↗

PubMed2001

Conservative functional treatment of ankle fractures.

Thirty-eight patients (mean age 49 years; range 19-91 years; nine of them over 60 years; 28 women, 10 men) suffering from an isolated Weber B fracture with a dislocation of less than 1 mm underwent functional therapy using a pneumatic ankle brace and were included in a prospective study. The clinical outcome was measured according to the Olerud-Molander ankle score. Functional therapy was finished in 34 cases successfully. Twenty-one patients were scored after 17 months on average (range 8-27 months) with the Olerud-Molander ankle score. A very good result was seen in 18 patients, including 12 with 100 points, a complete remission. The remaining 3 patients showed good results (1 had 90, 2 had 85). However, functional treatment failed in 4 cases due to secondary dislocation. These patients underwent surgery without further complications. The control group, 31 operated patients, did not show as good results. Functional therapy of stable Weber-B ankle fractures appears to be superior to surgery. We were able to avoid surgery in 90% of our patients and got better results than with patients undergoing open reduction and internal fixation.

Adolescent↗

PubMed2001

Confirmation of mendelian properties of heterodimeric fibrinogen molecules in a heterozygotic dysfibrinogenemia, "fibrinogen Amarillo," using gprphoresis to differentiate semifibrin molecules from fibrinogen and fibrin.

The fibrinogen molecule consists of two sets of Aalpha, Bbeta, and gamma chains assembled into a bilateral disulfide linked (Aalpha, Bbeta, gamma)2 structure. Cleavage of the two A-fibrinopeptides (FPA, Aalpha1-16) from normal Aalpha chains with arginine at position 16 (RFPA) by thrombin or the venom enzyme atroxin transforms fibrinogen into self-aggregating fibrin monomers (alpha, Bbeta, gamma)(2). Mutant Aalpha16R-->H fibrinopeptide (HFPA) cannot be cleaved from fibrinogen by atroxin. Many studies on heterozygous dysfibrinogenemias with this mutation suggested that incorporation of the mutant chains into the molecules was ordered in a manner yielding only (1) homodimeric normal (RFPARFPA) atroxin-coagulable molecules and (2) homodimeric abnormal (H(FPA)HFPA) atroxin-incoagulable molecules in equal quantities. Although heterodimeric molecules (RFPAHFPA) could not be found in studies on the intact protein, Meh et al. demonstrated their existence by showing that CNBr digests of fibrinogens from atroxin-treated Aalpha16R-->H heterozygotic dysfibrinogenemias consistently yielded N-terminal fragments (NDSKs) with partially resolved electrophoretic bands predominantly in between the NDSKs of fibrinogen and alpha-fibrin. An opportunity to confirm and better quantify the heterodimers arose with the recent development of a method (GPRphoresis) for identifying molecules lacking only one FPA, which is applied here in study of a newly presenting case of an Aalpha16R-->H dysfibrinogenemia, "fibrinogen Amarillo." GPRphoresis uses electrophoretic shifts, staged with GPRP-NH(2) to separate the self-aggregating fibrin monomers lacking both FPAs from weakly aggregating "semifibrin" molecules lacking one FPA An antifibrin alpha17-23 antibody is used to measure and differentiate the semifibrin from fibrinogen with FPA fully intact. Applying GPRphoresis to atroxin digests of fibrinogen Amarillo clearly demonstrated RFPARFPA, RFPAHFPA, and HFPAHFPA molecules in nearly perfect Mendelian 1:2:1 proportions. In turn, the high levels of the semifibrin in the terminal atroxin digests provide genetic phenotypic evidence supporting fidelity of the GPRphoresis method.

Dimerization↗

PubMed2001

Specific heterodimer formation by the cytoplasmic domains of the b and b' subunits of cyanobacterial ATP synthase.

The soluble domains of the b and b' subunits of the ATP synthase of the cyanobacterium Synechocystis PCC 6803 were expressed with His tags attached to their N-termini. Following purification, the polypeptides were characterized by chemical cross-linking, analytical ultracentrifugation, and circular dichroism spectroscopy. Treatment of a mixture of the soluble b and b' domains with a chemical cross-linking agent led to substantial formation of cross-linked dimers, whereas similar treatment of either domain by itself resulted in only trace formation of cross-linked species. The molecular weights of the domains of b and b' in solution at 20 degrees C, measured by sedimentation equilibrium, were 17 800+/-700 and 16 300+/-400, respectively, compared to calculated polypeptide molecular weights of 16 635 and 15 422, whereas a mixture of b and b' gave a molecular weight of 29 800+/-800. The sedimentation coefficient of an equimolar mixture was 1.73+/-0.03. The circular dichroism spectra of the individual polypeptides indicated helical contents in the range of 40-50%; the spectrum of the mixture revealed changes indicative of coiled-coil formation and a helical content of 60%. The results indicate that the cytosolic domains of the b and b' subunits exist individually as monomers but form a highly extended heterodimer when they are mixed together.

Centrifugation, Density Gradient↗

PubMed2001

[Conservative or operative treatment of humeral head fractures in the elderly?].

The humeral head fracture in the elderly represents an unresolved problem, which is reflected by the variety of existing therapeutic strategies ranging from conservative treatment to humeral head replacement. The main factors influencing the prognostic outcome are the fracture type, age of the patient and biologic criteria such as osteoporosis, blood supply at the fragments, and the degree of soft tissue trauma. For selection of the optimal treatment, the general condition of the patient, additional injuries and chronic diseases have to be respected as much as the patient's compliance and personal demands. According to experimental and clinical findings, for displaced two- and three-part fractures of the elderly patient minimal osteosynthesis and in the future plate osteosynthesis with angular stability should be preferred. For these fracture types, conservative treatment must be included in the therapeutic spectrum. In contrast, displaced four-part fractures and fracture dislocations are indications for primary humeral head replacement. This is explained by the fact that neither conservative treatment nor surgical reconstruction procedures meet the main goal of primary therapy, aiming for early painless mobilization and for timely discharging the elderly patients in their social environment.

Aged↗

PubMed2001

[Perioperative local instillation of ropivacaine for postoperative pain relief after surgery on extremities].

INTRODUCTION: The relief of postoperative pain remains one of the most important goals for adequate surgical patient care. METHODS: Prospective, randomised, double-blinded study, including 118 patients (67 M;/ 51 F; median age 43 years, min. 18, max. 74). Two groups were formed. In the verum group a wound instillation with ropivacaine was performed, in the control group not. Intensity of pain, demand for analgesics and satisfaction of the patient were evaluated postoperatively. In 10 patients ropivacaine plasma levels were measured. RESULTS: Significant postoperative pain relief and a decrease in analgesic consumption were found on instillation of ropivacaine. Compared to the control group, patients receiving ropivacaine were significantly more satisfied with the postoperative pain management. Potential toxic plasma levels were not found. CONCLUSION: By the presented method, the surgeon actively contributes to a significant reduction in postoperative pain and analgesic consumption. Furthermore, the patient's benefit is reflected by higher satisfaction with the pain management. Complications due to toxic plasma levels are not seen.

Adolescent↗

PubMed2001

[Crossed screw osteosynthesis of proximal humerus fractures].

Between March 1997 and October 1999 thirty-one patients with displaced proximal humeral fractures were treated with crossed screw osteosynthesis. Insertion of the screws was realized by using a deltoideo-pectoral approach placing the screws anteriorly and posteriorly in a crossed manner from the distal fragment into the humeral head. Additionally, in all two-part-fractures a tension band was applied. In all three-part-fractures, the greater tuberosity was reattached by additional screws. In 21 patients (14 female, 7 male, median age 62 years, 18-86) a clinical and radiological follow-up (median 18 months, 10-29) was obtained. Fractures were classified as two-part-fractures in 10 patients and as three-part-fractures in 11 patients. According to the Constant-Score, "excellent" and "good" results were achieved in 15 patients, "moderate" results were found in 3 patients. However, in 3 patients results were only "poor" (1 two-part-, 2 three-part-fractures). The complication rate was 29% (premature hardware removal due to head perforation in 3 cases; humeral head necrosis necessitating prosthetic replacement in 2 patients; secondary displacement in 1 case). Crossed screw osteosynthesis represents an justified alternative in the surgical treatment of displaced proximal humeral fractures permitting early functional therapy.

Adolescent↗

PubMed2001

[Fracture of the acromion. Diagnosis--treatment strategy--outcome].

The case of an 22-year-old man is presented, who sustained a dislocated fracture of the left acromion process and a not dislocated fracture of the left scapular body with a large subcutaneous décollement as well as a dammage of nervus axillaris occurring during a traffic accident. After resuming diagnostics by means of CT, a tension banding of the ventral part of the acromion and a plate osteosynthesis of the dorsal part was performed. 7 weeks after injury neurolysis of nervus axillaris has been done. 4 months after accident the patient shows a satisfying functional result in the Constant score. Diagnostic, treatment and functional results after operative treatment of dislocated fractures of the acromion are shown and discussed.

Acromion↗

PubMed2001

Fracture-dislocations of the elbow joint--strategy for treatment and results.

Between January 1993 and December 1996, 41 patients with fracture dislocation of the elbow joint were treated in our department. In 28 patients (median age 46 years, range 15-77 years; 16 male, 12 female), a clinical and radiological follow-up was obtained after median 34 months (range 12-59 months). In addition to the humero-ulnar dislocation, isolated fractures were present in 13 patients and combined fractures in 15 (all with involvement of the radial head). Primary neurological deficits were found in 7 and open fractures in 3 patients. In 7 patients, primary definitive surgical therapy was carried out by open reduction and internal fixation. A two-step surgical management (initial closed reduction and immobilization, 5 patients with external fixator, 7 with plaster; secondary open surgical procedure) was performed in 12 and conservative treatment in 9 patients. According to the Leipzig Elbow Score, taking subjective, clinical and radiological criteria into consideration, 4 patients achieved 'excellent' and 5 patients a 'good' result. Ten patients were scored 'moderate' and 9 'poor'. The rate of secondary complications necessitating revision was 36%. Poor results were primarily caused by extensive initial soft-tissue damage, delayed definitive surgical therapy, and ectopic heterotopic ossification. In contrast, fracture localization and degree of arthrosis were not of significant importance for the final outcome. In fracture dislocations, the goal is a primary definitive surgical treatment aiming for early postoperative physiotherapy.

Adolescent↗

PubMed2001

Arthroscopic-assisted simultaneous reconstruction of the posterior cruciate ligament and the lateral collateral ligament using hamstrings and absorbable screws.

Arthroscopic-assisted simultaneous reconstruction of the posterior cruciate ligament (PCL) and the lateral collateral ligament (LCL) using hamstring tendon grafts is described. The femoral tunnel is drilled through an incision over the medial femoral condyle and the tibial tunnel through the same skin incision used for harvesting the tendon graft. PCL reconstruction is performed using a 4-strand hamstring tendon graft and absorbable screw fixation. The tendon of the semitendinosus muscle of the uninvolved knee is used as a lateral loop for LCL reconstruction. After pulling the transplant through the fibular head, femoral fixation of the loop is made with an absorbable screw.

Absorbable Implants↗

PubMed2001

Transport of cytochrome c derivatives by the bacterial Tat protein translocation system.

An experimental system developed previously for the heterologous expression of c-type cytochromes in Escherichia coli Q1has been adapted to monitor protein transfer across the bacteria's cytoplasmic membrane. Apocytochrome, lacking the haem cofactor and probably in an unfolded state, was readily transferred across the cytoplasmic membrane when fused to a Sec-specific signal peptide. Furthermore, cytochrome fused to a signal peptide regarded as specific for the twin arginine transport (Tat) system was translocated in an unfolded state by the Sec apparatus. After maturation and folding in the cytoplasm, Tat-mediated transfer of holocytochrome to the periplasm occurred. We conclude that, in addition to the nature of the specific signal peptide, the folding state of a particular protein also governs its acceptance by a given transport system.

Amino Acid Sequence↗

PubMed2001

[Conservative treatment of dislocated proximal humeral fractures].

Between 11/1989 and 6/1998 52 patients (10 m., 42 f., age median 72 years, 31-88) with proximal humeral fractures have been treated by conservative means (angulation of humeral head > 45 degrees and/or shaft displacement > 1 cm and displacement of greater tuberosity > 0.5 cm). In 37 patients (71%, 31 f., 6 m., age median 75 years, 36-88) a clinical and radiological follow-up could be obtained after median 20 months (3-93). According to the Neer-classification, subcapital 2-part fractures were found in 19 cases and 3-part fractures in 12 cases. 4-part fractures were diagnosed in 6 cases. By using the Constant-Score, the final result was scored "excellent" in 10 patients and "good" in 13 patients. In 7 patients each the results achieved were "moderate" or "poor". The underlying cause for the poor results was primarily due to persisting painful impairment in range of motion and loss of strength. Radiologically, persisting axial deviation was present in 23 cases, arthrosis in 14 patients and humeral head necrosis in 8 patients. Most commonly, poor functional and radiological results occurred in 4-part fractures. However, conservative therapy of displaced 2-part and 3-part fractures is a considerable therapeutical option since the final results are predominantly good. In contrast, due to the poor results after conservative therapy 4-part fractures should be treated surgically.

Adult↗

PubMed2001

The fibrin intermediate, its place in the fibrinogen-fibrin transformation.

Our preceding study indicated that, in course of coagulation of human fibrinogen by thrombin, substantial production of the fibrin intermediate (alpha-profibrin) lacking only one fibrinopeptide A (FPA) precedes the formation of alpha-fibrin monomer lacking both FPAs. The plateau concentration of alpha-profibrin (20% of initial fibrinogen) appearing in reactions indicated, however, that the second FPA is released four times faster than the first. The study reported here confirms those findings, and provides new insight into the significance of differing rate constants for the production of alpha-profibrin and its conversion to alpha-fibrin. The intermediate could be isolated in a distinct electrophoretic band by electrophoresing partial thrombin digests at high concentrations. Its identity was verified by digesting it with CNBr and by demonstrating that its N-terminal domain, the NDSK fragment, both lacks an FPA and contains an FPA, unlike the NDSKs of the bands from fibrin which contained no FPA or the fibrinogen band that lacked no FPA. The single step isolation also enabled us to confirm the 15-20% plateau level of alpha-profibrin in course of thrombin reactions, well below the 37% maximum that would be expected if release of the first and second FPA proceeded independently with no difference in rate. The 37% maximum is observed in reactions with atroxin, and it is suggested that the abundant production of alpha-profibrin underlies the therapeutic utility of atroxin as a defibrinating agent. Gel chromatography procedures were optimized for isolation of alpha-profibrin/fibrin mixtures free of fibrinogen, the final step of which involves literal use of agarose gel as a filter to remove fibrin aggregates from the fibrinogen free fractions (aggregates are left behind in gel filtration, rather than their moving ahead in gel chromatography). Unlike human fibrinogen, rabbit fibrinogen does not yield much alpha-profibrin in course of its conversion to fibrin, less than 10% as determined by electrophoresis and comparison with abundant production with atroxin. This low production of alpha-profibrin conformed with conclusions from our early studies on the generalized Shwartzman reaction in rabbits, and we now infer that the low production of alpha-profibrin and rapid conversion to fibrin by rabbit fibrinogen underlies the unparalleled susceptibility of these animals toward fibrinoid formation in the generalized Shwartzman reaction.

Animals↗

PubMed2000

Expression of prokaryotic and eukaryotic cytochromes c in Escherichia coli.

C-type cytochromes from various sources show substantial structural conservation. For the covalent attachment of heme groups to apocytochromes, however, three different enzyme systems have been described so far. We have examined the ability of the heme ligation systems of Escherichia coli and of Saccharomyces cerevisiae to process cytochromes from S. cerevisiae, Paracoccus denitrificans, and Synechocystis sp. PCC 6803. E. coli's maturation system with at least eight different proteins accepted all these cytochromes for heme ligation. The single subunit heme lyase from S. cerevisiae mitochondria, on the other hand, failed to attach heme groups to cytochromes of prokaryotic origin.

Apoenzymes↗

PubMed2000

[Retropatellar autologous cartilage-bone transplantation. A treatment option in severe cartilage damage].

In a 32 years old professional handball layer, the micro-traumata typical of this game led to retropatellar cartilage lesion, which became sympthomatic following an distortion-impact trauma. Since the patient remains symptomatic after initial conservative treatment as well as arthroscopic chondroplastic, osteo-chondral transplantation was performed. There was a good functional result 6 months after surgery.

Adult↗

PubMed2000

[Proximal and distal humerus fractures in advanced age].

In contrast to distal humeral fractures, humeral head fractures represent a common injury to the old patient. For both fracture localizations osteoporosis and multi-morbidity are of significant importance. The classification for humeral head fractures in one-, two-, three- and four-part fractures is generally accepted. Valgus impacted head fractures as well as head-splitting fractures are considered a separate entity. In none or minimally displaced fractures good functional results are achieved by conservative means. Although numerous therapeutical procedure are offered in the treatment of displaced fractures of the proximal humerus the result are often disappointing. Generally, minimal invasive surgical procedures should be preferred. However, in dislocated multi-part fractures a primary humeral head replacement is often the treatment of choice. In patients with multifarious morbidity a conservative treatment is always to be included into the therapeutical considerations. Distal fractures of the humerus are classified into extraarticular, intraarticular uni-condylar and intraarticular bi-condylar fractures. The therapeutical recommendations, also in the elderly, is relatively homogeneous: primary open reduction and internal fixation (ORIF) should be carried out aiming for an early postoperative functional treatment. Depending from soft tissue conditions and accompanying injuries the functional results are often good or moderate and are generally comparable to those of younger patients. Following a correct indication for surgical intervention the main priority for both distal and proximal humeral fractures is an early definitive surgical treatment.

Aged↗