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J Harms

Publications and source records attributed to J Harms.

At least 19 recordsLinked to original sources
PubMed2005

Changes in quality of life after renal transplantation.

Quality of life is becoming an increasingly important concept in the evaluation of different therapeutic interventions. In this cross-sectional study, quality of life analyzed in 76 renal transplant patients was compared with 65 patients with end-stage renal disease (ESRD) awaiting transplantation. Both groups were asked to estimate their subjective quality of life by responding to a multidimensional questionnaire that sought information in the following areas: (1) sociodemographic data, (2) a personality test (Giessen-Test), (3) information about employment, (4) assessment of anxiety and depression (GHQ-28), (5) the SF-36 as an important measurement for quality of life, and (6) the ESRD symptom checklist-transplantation module. The sociodemographic profiles of both groups were similar. The SF-36 revealed significantly higher values for transplant recipients in terms of physical functioning (P < or = .001), general health perceptions (P < or = .01), social functioning (P < or = .01), and physical summary value (P < or = .001). The other tests (Giessen-Test and GHQ-28) and employment data showed no significant differences between the two samples. Collectively, the data demonstrate a considerable improvement in quality of life in renal transplant patients. Despite good physical recovery and higher quality of life after transplantation, the rate of vocational rehabilitation remained low, partially explained by the currently high levels of unemployment.

Affect↗
PubMed2005

Computerized CT-based 3D visualization technique in living related liver transplantation.

INTRODUCTION: For living donor liver transplantation (LDLT) accurate diagnostic workup is essential. Multiple imaging approaches are currently used. Problems arise in the assessment of vascular and bile duct anatomy, liver graft volume, and vascular territories involved. A 3D visualization system that improves anatomic assessment, allows interactive surgery planning, and acts as an intraoperative guide with enhanced precision is required. Refinements in computed tomography (CT) technology with the introduction of multidetector-row CT scanners and implementation of mathematical methods on computerized digital data has enabled CT-based 3D visualizations. MATERIALS AND METHODS: Sixteen LDLT candidates and three LDLT recipients were assessed by multislice CT examination. Image processing of the digital raw data for 3D visualization included segmentation and calculation of center lines. A hierarchical mathematical model representing the vascular and biliary tree was created. This allowed calculation of individual vascular territories. RESULTS: 3D CT-based visualization in LDLT facilitates diagnostic workup with high accuracy for analyses of vascular and bile duct variants, volumetry, and assessment of the optimal surgical splitting line of the living donor liver. Resultant areas of either arterial devascularization or venous congestion can be displayed and quantified preoperatively. The diagnostic method is of major impact on patient selection and directly influences intraoperative surgical guidance. The currently practiced "multiple imaging approach" approach, especially with regard to invasive diagnostics, can be avoided in the future.

Family↗
PubMed2002

[Optoelectronic display system for minimal invasive laparoscopic operations: initial experiences with new face-mounted display video eyeglasses].

A major aspect of efforts to improve minimally invasive surgery is the optimization of visualization, which is currently unsatisfactory due to the limited number of pixels in the monitors used, and inadequate alignment of the optical axis. Optical systems provided with commercially available head-mounted displays have failed to improve optical quality and significantly facilitate or improve laparoscopic surgery [2,3]. Innovations in the field of consumer video using a new optical prism and a high-resolution matrix (180,000 pixels) are the core elements of a new face-mounted display (FMD-Eye-Trek 700, Olympus Optical Co, Europe GmbH, Hamburg, Germany) that provides high image quality. This device has now been tested for the first time during laparoscopic procedures (n = 14) and combined laparoscopic-endoscopic procedures (n = 7) under clinical conditions. Impressive optical, ergonomic and surgeon-related benefits were established.

Equipment Design↗
PubMed2001

High resolution structure of the large ribosomal subunit from a mesophilic eubacterium.

We describe the high resolution structure of the large ribosomal subunit from Deinococcus radiodurans (D50S), a gram-positive mesophile suitable for binding of antibiotics and functionally relevant ligands. The over-all structure of D50S is similar to that from the archae bacterium Haloarcula marismortui (H50S); however, a detailed comparison revealed significant differences, for example, in the orientation of nucleotides in peptidyl transferase center and in the structures of many ribosomal proteins. Analysis of ribosomal features involved in dynamic aspects of protein biosynthesis that are partially or fully disordered in H50S revealed the conformations of intersubunit bridges in unbound subunits, suggesting how they may change upon subunit association and how movements of the L1-stalk may facilitate the exit of tRNA.

Bacterial Proteins↗
PubMed2001

Posterior C1-C2 fusion with polyaxial screw and rod fixation.

STUDY DESIGN: A novel technique of atlantoaxial stabilization using individual fixation of the C1 lateral mass and the C2 pedicle with minipolyaxial screws and rods is described. In addition, the initial results of this technique on 37 patients are described. OBJECTIVES: To describe the technique and the initial clinical and radiographic results for posterior C1-C2 fixation with a new implant system. SUMMARY OF BACKGROUND DATA: Stabilization of the atlantoaxial complex is a challenging procedure because of the unique anatomy of this region. Fixation by transarticular screws combined with posterior wiring and structural bone grafting leads to excellent fusion rates. The technique is technically demanding and has a potential risk of injury to the vertebral artery. In addition, this procedure cannot be used in the presence of fixed subluxation of C1 on C2 and in the case of an aberrant path of the vertebral artery. To address these limitations, a new technique of C1-C2 fixation has been developed: bilateral insertion of polyaxial-head screws in the lateral mass of C1 and through the pars interarticularis into the pedicle of C2, followed by a fluoroscopically controlled reduction maneuver and rod fixation. METHODS: After posterior exposure of the C1-C2 complex, the 3.5-mm polyaxial screws are inserted in the lateral masses of C1. Two polyaxial screws are then inserted into the pars interarticularis of C2. Drilling is guided by anatomic landmarks and fluoroscopy. If necessary, reduction of C1 onto C2 can be accomplished by manipulation of the implants, followed by fixation to the 3-mm rod. For definitive fusion, cancellous bone can be added. No structural bone graft or wiring is required. In selected cases, e.g., C1-C2 subluxation or fractures in young patients in whom only temporary fixation is necessary, the instrumentation can be removed after an appropriate time. Because the joint surfaces stay intact, the patient can regain motion in the C1-C2 joints. RESULTS: Thirty-seven patients underwent this procedure. No neural or vascular damage related to this technique has been observed. The early clinical and radiologic follow-up data indicate solid fusion in all patients. CONCLUSION: Fixation of the atlantoaxial complex using polyaxial-head screws and rods seems to be a reliable technique and should be considered an efficient alternative to the previously reported techniques.

Adolescent↗
PubMed2001

Multisurgeon assessment of surgical decision-making in adolescent idiopathic scoliosis: curve classification, operative approach, and fusion levels.

STUDY DESIGN: A multisurgeon assessment of curve classification, selection of operative approach, and fusion levels via a case study presentation. OBJECTIVES: To evaluate the ability of a group of scoliosis surgeons, not involved in the development of a new classification system, to accurately choose the corresponding curve classification of adolescent idiopathic scoliosis (AIS) cases and to evaluate the variability in the selection of operative approaches and both proximal and distal fusion levels in accordance with the new classification system in operative adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Recent evaluations using the King method for classifying AIS has shown poor intraobserver and interobserver reliability. A new, comprehensive classification system of AIS has been developed, but the result of a scoliosis surgeon's ability to apply the objective classification is unknown. In the surgical treatment of AIS, there are three choices for the operative approach (anterior, posterior, or both) and multiple choices for the selection of fusion levels. METHODS: During an AIS roundtable discussion at a spinal surgery meeting, 28 scoliosis surgeons were presented seven cases of operative AIS via good quality slides. Standard preoperative radiographs and clinical photographs were presented, and the reviewers were asked to classify the cases by a new classification system, choose their preferred surgical approach, and classify both proximal and distal fusion levels. RESULTS: For the seven cases presented, 84% of the curve types, 86% of lumbar modifiers, and 90% of sagittal thoracic modifiers were classified by the reviewers as described in the new classification. The case study found widely variable operative approaches and fusion levels chosen by the reviewers. There was an average of five different proximal (range, 4-8) and four different distal (range, 3-5) fusion levels chosen by the reviewers for each case. CONCLUSIONS: This case study assessment found a relatively high rate (84-90%) of agreement in curve classification of the individual components of a new classification system of AIS. This suggests the ability of a group of scoliosis surgeons to identify the specific criteria necessary for this new classification system of AIS. In addition, the high variability in selection of both operative approach and fusion levels confirms the current lack of standardized treatment paradigms. This further reinforces the need for a method to critically and objectively evaluate these variable treatments to determine the "best" radiographic and clinical results.

Adolescent↗
PubMed2001

Structural basis for the interaction of antibiotics with the peptidyl transferase centre in eubacteria.

Ribosomes, the site of protein synthesis, are a major target for natural and synthetic antibiotics. Detailed knowledge of antibiotic binding sites is central to understanding the mechanisms of drug action. Conversely, drugs are excellent tools for studying the ribosome function. To elucidate the structural basis of ribosome-antibiotic interactions, we determined the high-resolution X-ray structures of the 50S ribosomal subunit of the eubacterium Deinococcus radiodurans, complexed with the clinically relevant antibiotics chloramphenicol, clindamycin and the three macrolides erythromycin, clarithromycin and roxithromycin. We found that antibiotic binding sites are composed exclusively of segments of 23S ribosomal RNA at the peptidyl transferase cavity and do not involve any interaction of the drugs with ribosomal proteins. Here we report the details of antibiotic interactions with the components of their binding sites. Our results also show the importance of putative Mg+2 ions for the binding of some drugs. This structural analysis should facilitate rational drug design.

Anti-Bacterial Agents↗
PubMed2001

Crystal structures of complexes of the small ribosomal subunit with tetracycline, edeine and IF3.

The small ribosomal subunit is responsible for the decoding of genetic information and plays a key role in the initiation of protein synthesis. We analyzed by X-ray crystallography the structures of three different complexes of the small ribosomal subunit of Thermus thermophilus with the A-site inhibitor tetracycline, the universal initiation inhibitor edeine and the C-terminal domain of the translation initiation factor IF3. The crystal structure analysis of the complex with tetracycline revealed the functionally important site responsible for the blockage of the A-site. Five additional tetracycline sites resolve most of the controversial biochemical data on the location of tetracycline. The interaction of edeine with the small subunit indicates its role in inhibiting initiation and shows its involvement with P-site tRNA. The location of the C-terminal domain of IF3, at the solvent side of the platform, sheds light on the formation of the initiation complex, and implies that the anti-association activity of IF3 is due to its influence on the conformational dynamics of the small ribosomal subunit.

Binding Sites↗
PubMed2001

Ribosomal crystallography: from poorly diffracting microcrystals to high-resolution structures.

The cellular organelles translating the genetic code into proteins, the ribosomes, are large, asymmetric, flexible, and unstable ribonucleoprotein assemblies, hence they are difficult to crystallize. Despite two decades of intensive effort and thorough searches for suitable sources, so far only three crystal types have yielded high-resolution structures: two large subunits (from an archaean and from a mesophilic eubacterium) and one thermophilic small subunit. These structures have added to our understanding of decoding, have revealed dynamic aspects of the biosynthetic process, and have indicated the strategies adopted by ribosomes for interacting between themselves as well as with inhibitors, factors and substrates.

Archaea↗
PubMed2001

[Transoral atlanto-axial plate fixation in the treatment of a malunited dens fracture and secondary atlanto-axial instability].

INTRODUCTION: A case of a 22-year-old patient with a malunited dens fracture and secondary atlanto-axial instability is presented. The significant narrowing of the spinal canal due to the atlanto-axial instability was associated with anterior myelon compression and neurological deficit. METHODS: A transoral approach with odontoid resection and anterior atlanto-axial plate fixation was performed. With this technique the atlanto-axial subluxation was reduced and the myelon was decompressed. RESULTS: The postoperative course was uneventful. The follow-up showed a complete remission of the neurological deficit and a bony fusion of the atlanto-axial joints. CONCLUSIONS: The presented case illustrates the importance of an accurate initial diagnosis of the degree of instability and the need for short-term follow-up examinations. If atlanto-axial pseudarthrosis or malunion with anterior spinal cord compression occurs, a transoral procedure with odontoid resection and atlanto-axial plate fixation seems to be an excellent salvage procedure.

Adult↗
PubMed2001

Three-dimensional navigated laparoscopic ultrasonography: first experiences with a new minimally invasive diagnostic device.

BACKGROUND: A three-dimensional (3D) display of diagnostic imaging methods is technically feasible and increasingly important. However, the technical integration of laparoscopic ultrasound and 3D image reconstruction has not yet been realized. For this purpose, an electromagnetic navigation system was integrated into the tip of a conventional laparoscopic ultrasound probe. This first experience with a certified prototype of a navigated 3D laparoscopic ultrasound probe is reported. METHODS: Navigated 3D laparoscopic ultrasound was compared with the imaging data of 3D-navigated transcutaneous ultrasound and 3D computed tomography (CT) scan. The 3D CT scan served as the "gold standard." Clinical applicability, imaging quality, diagnostic potential, and accuracy in volumetric assessment of various well-defined hepatic lesions were analyzed. RESULTS: Navigated 3D laparoscopic ultrasound facilitates exact definition of tumor location and margins. As compared with the "gold standard" of the 3D CT scan, 3D laparoscopic ultrasound has a mild tendency to underestimate the volume of the region of interest (ROI) (D 3.1%). A comparison of 3D laparoscopy and transcutaneous 3D ultrasonography clearly demonstrated that the former is more accurate for volumetric assessment of the ROI. CONCLUSIONS: Three-dimensional laparoscopic ultrasound imaging with a navigated probe is technically feasible. The technique facilitates detailed ultrasound evaluation of laparoscopic procedures involving visual, in-depth, and volumetric perception of complex liver pathologies. Navigated 3D laparoscopic ultrasound may have the potential to improve the significance of laparoscopic ultrasonography, and additionally to become a valuable technology for planning and improving interventions guided by laparoscopic ultrasound.

Carcinoma, Hepatocellular↗
PubMed2001

Diagnosing acute liver graft rejection: experimental application of an implantable telemetric impedance device in native and transplanted porcine livers.

BACKGROUND AND AIMS: Diagnosis of acute rejection is a complex and persistent problem in liver transplantation. Focused on the use of proprietary impedance technology a porcine liver model was designed to provide immediate information for differentiation of normal and acute rejecting tissue by an implantable telemetric device. METHODS: Electrical impedance was analyzed by electrodes implanted in vitro and in vivo in the liver of pigs, where impedance is derived from measurements of voltage transients produced in response to programmed current pulses. Consequent electric recordings in porcine livers after transplantation and after mere laparotomy were evaluated in relation to biochemical parameters and histological results of liver biopsies. RESULTS: Acute rejection was correctly predicted in all cases and correctly excluded in the remaining 32 biopsy related impedance recordings (P<0.004). Impedance measurements not only correlated with the diagnosis from liver biopsy specimen (r=0.84, P<0.0001) but also exemplified the severity of histological acute rejection. CONCLUSION: Impedance analysis reveals evident physiologic relation of acute liver graft rejection and electrical organ properties. Electrodes implanted in transplanted porcine livers allow running less invasive monitoring and thus early detection of rejection. The technology may have broad value in providing an immediate diagnosis of acute rejection, reducing unnecessary patient anxiety and eliminating the significant expenses associated with multiple referrals, expensive sample handling and tissue analysis.

Acute Disease↗
PubMed2001

Adolescent idiopathic scoliosis: a new classification to determine extent of spinal arthrodesis.

BACKGROUND: The lack of a reliable, universally acceptable system for classification of adolescent idiopathic scoliosis has made comparisons between various types of operative treatment an impossible task. Furthermore, long-term outcomes cannot be determined because of the great variations in the description of study groups. METHODS: We developed a new classification system with three components: curve type (1 through 6), a lumbar spine modifier (A, B, or C), and a sagittal thoracic modifier (-, N, or +). The six curve types have specific characteristics, on coronal and sagittal radiographs, that differentiate structural and nonstructural curves in the proximal thoracic, main thoracic, and thoracolumbar/lumbar regions. The lumbar spine modifier is based on the relationship of the center sacral vertical line to the apex of the lumbar curve, and the sagittal thoracic modifier is based on the sagittal curve measurement from the fifth to the twelfth thoracic level. A minus sign represents a curve of less than +10 degrees, N represents a curve of 10 degrees to 40 degrees, and a plus sign represents a curve of more than +40 degrees. Five surgeons, members of the Scoliosis Research Society who had developed the new system and who had previously tested the reliability of the King classification on radiographs of twenty-seven patients, measured the same radiographs (standing coronal and lateral as well as supine side-bending views) to test the reliability of the new classification. A randomly chosen independent group of seven surgeons, also members of the Scoliosis Research Society, tested the reliability and validity of the classification as well. RESULTS: The interobserver and intraobserver kappa values for the curve type were, respectively, 0.92 and 0.83 for the five developers of the system and 0.740 and 0.893 for the independent group of seven scoliosis surgeons. In the independent group, the mean interobserver and intraobserver kappa values were 0.800 and 0.840 for the lumbar modifier and 0.938 and 0.970 for the sagittal thoracic modifier. These kappa values were all in the good-to-excellent range (>0.75), except for the interobserver reliability of the independent group for the curve type (kappa = 0.74), which fell just below this level. CONCLUSIONS: This new two-dimensional classification of adolescent idiopathic scoliosis, as tested by two groups of surgeons, was shown to be much more reliable than the King system. Additional studies are necessary to determine the versatility, reliability, and accuracy of the classification for defining the vertebrae to be included in an arthrodesis.

Adolescent↗
PubMed2000

Structure of functionally activated small ribosomal subunit at 3.3 angstroms resolution.

The small ribosomal subunit performs the decoding of genetic information during translation. The structure of that from Thermus thermophilus shows that the decoding center, which positions mRNA and three tRNAs, is constructed entirely of RNA. The entrance to the mRNA channel will encircle the message when a latch-like contact closes and contributes to processivity and fidelity. Extended RNA helical elements that run longitudinally through the body transmit structural changes, correlating events at the particle's far end with the cycle of mRNA translocation at the decoding region. 96% of the nucleotides were traced and the main fold of all proteins was determined. The latter are either peripheral or appear to serve as linkers. Some may assist the directionality of translocation.

Base Pairing↗
PubMed2000

Do radiographic parameters correlate with clinical outcomes in adolescent idiopathic scoliosis?

STUDY DESIGN: A radiographic assessment has been developed to include coronal, sagittal, and axial parameters. OBJECTIVE: To determine the correlation of postoperative radiographic results and percentage postoperative radiographic improvement with patient clinical self-assessment. SUMMARY OF BACKGROUND DATA: With the increasing interest in outcome studies, the authors wanted to determine whether Scoliosis Research Society clinical questionnaire results would correlate with objective radiographic improvement. METHODS INCLUSION CRITERIA: adolescent idiopathic scoliosis treated with anterior or posterior instrumentation, a solid fusion, minimum 2-year follow-up, and a completed postoperative Scoliosis Research Society questionnaire. Seventy-eight patients met the criteria. Measurements included in the radiographic score: Cobb angles of the coronal curve, C7 to the center sacral vertical line, apical translation, apical vertebral rotation, T1 rib angle, end-instrumented vertebrae angulation, angulation of the disc below the end-instrumented vertebra, and curve type. Sagittal measurements included T2-T12, T5-T12, T2-T5, T12-L2, and L1-S1. RESULTS: The preoperative radiographic score of these 78 patients was mean 60.1 +/- 9.7 (range 41-88, maximum radiographic score, 100). The 2-year postoperative radiographic score was mean 83.8 +/- 8.8 (range, 65-100). The median Scoliosis Research Society questionnaire score was 98 +/- 12.3 (range, 58-116, maximum score, 125, showing that the patient is highly satisfied and asymptomatic). The postoperative radiographic score versus the questionnaire score showed a Spearman rank correlation of 0.04 (P = 0.68, little or no correlation throughout). Percentage improvement of the radiographic score versus the questionnaire score showed a Spearman rank correlation of 0.1 (P = 0.38, little or no correlation throughout). CONCLUSION: In this initial group of patients, the radiographic assessment shows a significant improvement between preoperative and 2-year postoperative scores. However, little correlation between the radiographic assessment and the questionnaire scores was found in this adolescent population, suggesting that separate analyses of radiographic and clinical outcome data are required when evaluating results of postoperative scoliosis surgery.

Adolescent↗
PubMed2000

The effect of continued posterior spinal growth on sagittal contour in patients treated by anterior instrumentation for idiopathic scoliosis.

STUDY DESIGN: Retrospective analysis of radiographs on a prospective cohort of patients undergoing anterior instrumentation for thoracic idiopathic scoliosis. OBJECTIVES: To analyze the change in sagittal profile after growth. SUMMARY OF BACKGROUND DATA: The authors previously reported some advantages of anterior instrumentation for treatment of thoracic idiopathic scoliosis. However, postsurgery hyperkyphosis has resulted in some patients, especially those who were skeletally immature at the time of surgery. METHODS: Inclusion criteria required that participants have thoracic idiopathic scoliosis treated with anterior instrumentation and a confirmed solid fusion, no rod breakage, and a minimum follow-up period of 2 years. The 47 patients meeting the criteria were divided into a study group of 10 patients who were Risser 0 at the time of surgery and a control group of 37 patients who were Risser 1 to 5. Progressive sagittal kyphosis was defined as an increase of 10 degrees or more (T5-T12) after surgery. RESULTS: Sagittal progression greater than 10 degrees (average, 15 degrees ) occurred in 6 of 10 patients (60%) in the study group (Risser 0). Five patients progressed from 10 degrees to 19 degrees, and one patient from 20 degrees to 30 degrees. In contrast, sagittal progression occurred in only 10 of 37 patients (27%) in the control group (Risser 1 to 5). CONCLUSIONS: Some patients with thoracic adolescent idiopathic scoliosis treated with anterior instrumentation may be at risk for progressive sagittal kyphosis secondary to growth. Skeletal immaturity (Risser 0) appears to be a risk factor. In these immature patients, preserving the sagittal profile with intervertebral spacers, rigid rods, and bone graft (allowing for an average 15 degrees increase of kyphosis with growth) may be appropriate.

Adolescent↗
PubMed2000

[Rationale and selection for combined procedures in colonic dysplasias and T1 carcinomas. Laparoscopic-endoscopic local wall excision and segment resection].

Combined endoscopic-laparoscopic procedures may offer an interesting therapeutic option in cases of benign colonic lesions and early T 1 carcinoma where endoluminal resection is not feasible, but oncological resection is not (yet) required. Combined procedures such as the laparoscopically assisted endoscopic resection, the endoscopically assisted laparoscopic wedge or transluminal resection, or the segmental resection can be performed. Experience with this technique is still limited, but has shown that the invasiveness can be reduced by endoscopically guided local excision. If it is possible to keep the incidence of secondary operations low, combined laparoscopic/endoscopic interventions could occupy a valuable place in the therapeutic spectrum.

Adult↗