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W Weber

Publications and source records attributed to W Weber.

At least 109 records · Page 6Linked to original sources
PubMed1999

Accuracy of intravascular microcatheter pressure measurements: an experimental study.

Intravascular pressure measurements are considered useful for the monitoring and assessment of endovascular treatment effects in intracranial vascular malformations. Experimental data on the accuracy of these measurements are limited. A flow phantom with defined intraluminal pressures and pulsatility flow waveforms was used in this study. Microcatheters commercially available for neuroendovascular procedures (length 140-155 cm), with different outer (0.5-0.83 mm) and inner (0.3-0.53 mm) diameters, were introduced into the phantom in the direction of flow. In a static experiment, pressure values from 0 to 75 mmHg were applied, and in the dynamic part of the experiment mean pressure values from 25 to 65 mmHg, with a pulsatile amplitude from 70 to 170 mmHg were employed. In the static experiment, there was a linear relationship between the pressure values obtained through the microcatheters and the local transducer of the flow phantom. The pulsatile experiments showed increased damping of the pressure waveforms with decreasing inner diameter of the microcatheters. However, the mean pressure values remained accurate. This experimental study has shown that mean pressure values can be accurately measured through microcatheters from 0.3-0.5 mm inner diameter and more than 140 cm in length. In vivo pressure measurements during interventional procedures are therefore reproducible and can be used for monitoring of embolization effects in patients.

Blood Flow Velocity↗
PubMed1999

Assessment of pulmonary lesions with 18F-fluorodeoxyglucose positron imaging using coincidence mode gamma cameras.

UNLABELLED: Accurate assessment of lung carcinoma remains a significant clinical problem, often leading to surgical procedures without curative potential. PET with 18F-fluorodeoxyglucose (FDG) has shown promise in differentiating benign from malignant lesions and in staging the extent of disease, resulting in improved treatment at a significant cost savings. This multicenter prospective study used dual-detector coincidence imaging with FDG to categorize pulmonary lesions as benign or malignant. The goal of this study was to determine the sensitivity and specificity of dual-detector coincidence imaging of FDG in patients with pulmonary lesions who were scheduled to have a diagnostic procedure for histopathologic confirmation. METHODS: A total of 96 patients with pulmonary lesions with a lesion size ranging from 1 to 7 cm with a mean of 3.44 cm based on their chest radiograph or CT scan were studied using FDG scans with a dual-detector coincidence detection system. An additional 24 patients were entered as control subjects. The studies of 120 subjects were interpreted in random order by three physicians experienced in the use of FDG in patients with lung cancer. Surgical pathology was used as the standard for identifying malignant lesions. RESULTS: There was 94% agreement between the readers in the independent interpretation of the FDG studies. In the 96 patients with pulmonary lesions, FDG studies were 97% sensitive and 80% specific in identifying proven malignant lesions. CONCLUSION: The results of this prospective study provide evidence that dual-detector coincidence imaging with FDG provides an accurate, sensitive and specific means of diagnosing malignancy in patients with pulmonary lesions.

Case-Control Studies↗
PubMed1999

18F-FDG PET studies in patients with extratemporal and temporal epilepsy: evaluation of an observer-independent analysis.

UNLABELLED: The aim of this study was to evaluate an observer-independent analysis of 18F-fluorodeoxyglucose (FDG) PET studies in patients with temporal or extratemporal epilepsy. METHODS: Twenty-seven patients with temporal epilepsy and 22 patients with extratemporal epilepsy were included in the study. All patients with temporal epilepsy and 7 patients with extratemporal epilepsy underwent surgical treatment. In patients who showed significant postoperative improvement (temporal, n = 23; extratemporal, n = 6), the epileptogenic focus was assumed to be located in the area of surgical resection. In extratemporal epilepsy patients who did not undergo surgery, the focus localization was determined using a combination of semiology, ictal and interictal electroencephalography, [99mTc]ethyl cysteinate dimer SPECT, MRI and [11C]flumazenil PET. Visual analysis was performed by two experienced and two less experienced blinded observers using sagittal, axial and coronal images. In the automated analysis after anatomic standardization and generation of three-dimensional stereotactic surface projections (SSPs), a pixelwise comparison of 18F-FDG uptake with an age-matched reference database (n = 20) was performed, resulting in z score images. Pixels with the maximum deviation were detected, summarized and attached to one of 20 predefined surface regions of interest. For comparison with 18F-FDG PET and MR images, three-dimensional overlay images were generated. RESULTS: In patients with temporal epilepsy, the sensitivity was comparable for visual and observer-independent analysis (three-dimensional SSP 86%, experienced observers 86%-90%, less experienced observers 77%-86%). In patients with extratemporal epilepsy, three-dimensional SSP showed a significantly higher sensitivity in detecting the epileptogenic focus (67%) than did visual analysis (experienced 33%-38%, each less experienced 19%). In temporal lobe epilepsy, there was moderate to good agreement between the localization found with three-dimensional SSP and the different observers. In patients with extratemporal epilepsy, there was a high interobserver variability and only a weak agreement between the localization found with three-dimensional SSP and the different observers. Although three-dimensional SSP detected multiple lesions more often than visual analysis, the determination of the highest deviation from the reference database allowed the identification of the epileptogenic focus with a higher accuracy than subjective criteria, especially in extratemporal epilepsy. CONCLUSION: Three-dimensional SSP increases sensitivity and reduces observer variability of the analysis of 18F-FDG PET images in patients with extratemporal epilepsy and is, therefore, a useful tool in the evaluation of this patient group. The benefit of this analytical approach in patients with temporal epilepsy is less apparent.

Adolescent↗
PubMed1999

Peripheral effects of the kappa-opioid agonist EMD 61753 on pain and inflammation in rats and humans.

The objective of the present study was to evaluate the effects of EMD 61753 (asimadoline), a kappa-opioid receptor agonist with restricted access to the central nervous system, on postoperative pain in patients who underwent knee surgery and on nociceptive thresholds and inflammation in rats treated with Freund's complete adjuvant. Patients treated with EMD 61753 (10 mg p.o.) tended to report an increase in pain, as evaluated by a visual analog scale and by the time to the first request for and the total amount of supplemental analgesic medication. The global tolerability of EMD 61753 was assessed as significantly inferior to that of a placebo by the investigator. In rats, the bilateral intraplantar (i.pl.) injection of EMD 61753 (0.1-3.2 mg) resulted in dose-dependent antinociception in both inflamed and noninflamed paws, with a peak at 5 min after injection, as evaluated by the paw pressure method. However, at later time points (1 h-4 days), a significant decrease in the paw pressure threshold was observed, confirming its tendency toward a hyperalgesic action in humans. This was accompanied by an increase in paw volume and paw temperature, with a peak at 6 h after injection. EMD 61753 (1.6 mg)-induced analgesia was blocked by the peripheral opioid receptor antagonist naloxone methiodide (2.5-10 mg/kg s.c.) and by the kappa receptor antagonist nor-binaltorphimine (0.1 mg; i.pl.). In contrast, EMD 61753 (1.6 mg)-induced hyperalgesia and increases in paw volume and paw temperature were blocked neither by naloxone methiodide (10-40 mg/kg s.c.) nor by dizocilpine maleate (0.003-0.009 mg i.pl.), a N-methyl-D-aspartic acid receptor antagonist. These data show differentially mediated peripheral actions of EMD 61753: kappa-opioid receptor-induced analgesia and nonopioid, non-N-methyl-D-aspartic acid hyperalgesic and proinflammatory effects.

Acetamides↗
PubMed1999

Synthesis and radiopharmacology of O-(2-[18F]fluoroethyl)-L-tyrosine for tumor imaging.

UNLABELLED: The aim of the study was to develop a simple 18F-labeled amino acid as a PET tracer for cerebral and peripheral tumors. O-(2-[18F]fluoroethyl)-L-tyrosine (L-[18F]FET) was synthesized and biologically evaluated. Results of the first human PET study are reported. METHODS: No carrier added (n.c.a.) and D-[18F]FET were prepared by 18F-fluoroethylation of L- and D-tyrosine in a two-step procedure. Biodistribution studies were performed in mice. The metabolic fate of L-[18F]FET was investigated in plasma, brain, tumor and pancreatic tissue samples using chromatographic procedures. Tumor uptake studies were performed in mammary carcinoma-bearing mice and in mice with the colon carcinoma SW 707. In a human PET study, a 59-y-old man with a recurrent astrocytoma was imaged using n.c.a. L-[18F]FET. RESULTS: Synthesis of [18F]FET was accomplished in about 50 min with an overall radiochemical yield of 40%. The uptake of L-[18F]FET in the brain of mice reached a level >2% ID/g between 30 and 60 min postinjection. The brain uptake of the D-isomer was negligible, indicating blood-brain barrier penetration by a specific amino acid transport system. L-[18F]FET is not incorporated into proteins. High-performance liquid chromatography (HPLC) analysis of brain, pancreas and tumor homogenates as well as plasma samples of mice at 10, 40 or 60 min postinjection showed only unchanged L-[18F]FET. Activity uptake in the bone did not exceed 2% ID/g at 40 min postinjection. The brain uptake of L-[18F]FET in mice bearing mammary carcinomas and colon carcinomas reached 7.1%+/-1.2% ID/g and 6.4%+/-1.7% ID/g 1h postinjection, respectively. In the first human study, L-[18F]FET-PET allowed a clear delineation of a recurrent astrocytoma. Thirty-five minutes postinjection, the tumor-to-cortex ratio was >2.7. A tumor-to-blood ratio >1.5 was reached at 30 min postinjection and continued to increase. No significant activity accumulation was observed in peripheral organs after approximately 40 min postinjection. CONCLUSION: The high in vivo stability of L-[18F]FET, its fast brain and tumor uptake kinetics, its low accumulation in nontumor tissue and its ease of synthesis strongly support further evaluation of L-[18F]FET as an amino acid tracer for cerebral and peripheral tumors.

Animals↗
PubMed1998

Percutaneous transluminal angioplasty of intracranial artery stenosis: clinical results in 24 patients.

Circumscribed stenotic lesions of the intracranial arteries can cause cerebral ischemia by hemodynamic and/or thromboembolic mechanisms. Anticoagulation therapy, antiplatelet therapy, and bypass surgery are treatment strategies that have no direct impact on the underlying lesion. This study summarizes the experience of a single institution at which percutaneous transluminal angioplasty (PTA) of intracranial atherosclerotic stenoses was performed. The authors performed a retrospective analysis of 24 consecutive patients. Their medical histories (cardiovascular risk factors, current clinical signs and symptoms and their duration, previous stroke[s], and medical treatment) were evaluated together with findings from previous imaging studies. The site and degree of the stenoses to be treated (target lesion) were identified with the use of ultrasound and angiography studies. Additional vascular stenoses were noted. Percutaneous transluminal angioplasty was performed using single-lumen balloon microcatheters with appropriate diameters. The results of PTA were correlated with angiographic and ultrasound findings and the clinical outcome. Significant cardiovascular risk factors and clinical signs and symptoms related to the target lesion that persisted despite medical treatment were identified in all patients except one. The duration of symptoms varied from several days to 8 months. Previous stroke had occurred in four patients. The degree of stenosis was classified as "high grade" in 10 patients and as "subtotal" in 14. The target lesion (stenosis) was located in the anterior circulation in eight patients (four in the internal carotid and four in the middle cerebral arteries). Stenoses of posterior circulation vessels were treated in 16 patients (nine vertebral, six basilar, and one posterior cerebral arteries). Recanalization was rated "complete" in 15 patients and sufficient in six patients. In three patients residual stenosis remained. Complications were encountered in seven patients: two asymptomatic dissections, one transient vessel occlusion, one vessel occlusion with subsequent stroke, and three ischemic lesions likely due to thromboembolism, two of which caused only transient neurological symptoms. Percutaneous balloon dilation proved effective in the treatment of intracranial atherosclerotic stenosis. There are, however, potential complications and experience with this procedure is only limited. Long-term results need to be determined. The authors conclude from their preliminary results that PTA may be an alternative to bypass surgery and conservative management and may be considered for patients in whom ischemic neurological symptoms persist despite medical treatment.

Journal Article↗
PubMed1998

Crystallization and preliminary X-ray crystallographic analysis of the EGF receptor ectodomain.

Crystallization of the hydrophilic ectodomain of the epidermal growth factor (EGF) receptor has been accomplished in the presence of the ligand EGF. Two different crystal forms have been obtained, one of which was suitable for X-ray analysis. The space group of this form has been assigned to P21212 with unit-cell dimensions of a = 207.4, b = 113.3 and c = 120.4 A. A native data set has been recorded and a heavy-atom search is currently under way. Diffraction from these crystals, however, is limited to low resolution and extensive trials to improve crystal quality further have all failed. To analyse the molecular shape and aggregation of the receptor protein in solution, small-angle X-ray diffraction and dynamic light-scattering techniques have been applied. Synchrotron radiation in combination with cryo-techniques is essential for data collection because of the high solvent content and radiation sensitivity.

Animals↗
PubMed1998

Neuropsychological function in adults with attention-deficit hyperactivity disorder.

BACKGROUND: Recent studies indicate that attention-deficit hyperactivity disorder (ADHD) persists into adulthood, but little is known about the neuropsychological features of adult ADHD. Our objective was to assess neuropsychological functioning in adults with ADHD with a battery of executive function tests. METHODS: Subjects were 64 unmedicated adults, 19-59 years of age, with DSM-III-R ADHD of childhood onset who met criteria for ADHD when referred in adulthood and 73 non-ADHD controls of similar age and gender. Information on neuropsychological performance was obtained in a standardized manner blind to clinical status. RESULTS: Compared with controls, adults with ADHD were significantly impaired on measures of vigilance, semantic encoding for verbal memory, and written arithmetic, irrespective of age, gender, psychiatric comorbidity, or presence of learning disability. Despite comparable educational level and IQ, ADHD adults had a trend to lower occupational attainment and had significantly more academic problems in school. CONCLUSIONS: These executive, attention, and achievement dysfunctions demonstrated in adults with ADHD provide additional support for the validity of the syndrome in adults.

Adult↗
PubMed1998

Positron emission tomography in non-Hodgkin's lymphoma: assessment of chemotherapy with fluorodeoxyglucose.

Positron emission tomography (PET) using F-18 fluorodeoxyglucose (FDG) was performed in non-Hodgkin's lymphoma (NHL), which is known to be highly responsive to chemotherapy, but also yields variable treatment results to answer the following questions: (1) What is the extent and time course of changes in FDG utilization in response to chemotherapy? (2) Are the changes of FDG uptake at early time points of chemotherapy predictive for therapy outcome? (3) Which quantitative FDG parameter provides the most sensitive measures of initial tumor response? Dynamic PET scans were performed in 11 patients at baseline and 1 and 6 weeks after initiation of chemotherapy. Based on attenuation corrected images acquired 30 to 60 minutes postinjection, standardized uptake values (SUV) were determined. Arterial input functions were estimated from vascular F-18 activity and the metabolic rates for FDG (MRFDG) were calculated using Patlak analysis. Before chemotherapy, high FDG uptake was found in all lesions (SUV[max] 13.3 +/- 4.2). Seven days after initiation of chemotherapy, tumor FDG uptake decreased 60% (SUV[max]). A further decrease of 42% was seen at day 42 resulting in a total decrease of 79% from baseline to day 42. During a follow-up of 16.0 +/- 4.2 months, six of the 11 patients continued to show complete remission. Seven days after initiation of chemotherapy, this group of patients displayed significantly lower mean MRFDG than the group of patients with relapse. At day 42, all parameters of FDG uptake showed a significant difference for both patient groups. The relative change of MRFDG from baseline to day 42, as well as from day 7 to day 42, was significantly larger as compared with SUV parameters. Standard chemotherapy of patients with NHL causes rapid decrease of tumor FDG uptake as early as 7 days after treatment, which continues to decline during therapy, indicating the sensitivity of metabolic signals to chemotherapeutic interventions. FDG uptake at 42 days after therapy was superior in prediction of long-term outcome over day 7 parameters. Dynamic data acquisition combined with Patlak analysis of FDG kinetics may provide superior information in therapy monitoring.

Adult↗
PubMed1998

Use of mesenchymal stem cells in a collagen matrix for Achilles tendon repair.

This investigation tested the hypothesis that delivering mesenchymal stem cell-seeded implants to a tendon gap model results in significantly improved repair biomechanics. Cultured, autologous, marrow-derived mesenchymal stem cells were suspended in a collagen gel delivery vehicle; the cell-gel composite was subsequently contracted onto a pretensioned suture. The resulting tissue prosthesis was then implanted into a 1-cm-long gap defect in the rabbit Achilles tendon. Identical procedures were performed on the contralateral tendon, but only the suture material was implanted. The tendon-implant constructs were evaluated 4, 8, and 12 weeks later by biomechanical and histological criteria. Significantly greater load-related structural and material properties were seen at all time intervals in the mesenchymal stem cell-treated tendons than in the contralateral, treated control repairs (p < 0.05), which contained suture alone with natural cell recruitment. The values were typically twice those for the control tissues at each time interval. Load-related material properties for the treated tissues also increased significantly over time (p < 0.05). The treated tissues had a significantly larger cross-sectional area (p < 0.05), and their collagen fibers appeared to be better aligned than those in the matched controls. The results indicate that delivering mesenchymal stem cell-contracted, organized collagen implants to large tendon defects can significantly improve the biomechanics, structure, and probably the function of the tendon after injury.

Achilles Tendon↗
PubMed1998

[Managed care--an example for future structural developments in health care. Reflections on a informational visit on direction and administration of medical centers in east USA].

While the different national health systems merge structurally, cost expansion in health care is a global challenge. Structural reforms have been developed during recent years in the USA which can be summarized as "managed care". They are characterized by the evolution of an economically orientated system, in which units of medical therapy are generally handled like conventional economically goods. In managed-care models, patients are deliberately directed to the most economic forms of therapy. The spectrum of medical interventions as well as diagnostic or therapeutic patterns are predefined by a system of contracted guidelines, which lead to a standardization of processes. Financing and medical executive responsibilities fuse. The autonomy of medical decisions is clearly reduced to enforce and integrated and economically oriented steering of the health system. Leadership is no longer primarily confined to doctors or scientists. It is progressively shifting to financing institutions, managing directors or insurance companies. Structural changes currently are expanding rapidly in the U.S. and have meanwhile led to marked regional reductions of medical costs. Nevertheless, the US model is still far more expensive compared to the German system. Historical development, current concepts of US-managed care, its potential influence and general applicability to the German situation are discussed in an overview.

Academic Medical Centers↗
PubMed1998

[Diagnosis of bronchial carcinoma].

In addition to conventional chest X-rays in AP and lateral projection, computed tomography of the chest, upper abdomen, and head, precutaneous ultrasonography of the abdomen, and bone scintigraphy represent the standard procedures for the primary diagnosis and staging of bronchial carcinoma. Magnetic resonance imaging should be reserved for special situations and patients with allergy to i.v. contrast medium. The clinical value of positron emission tomography (PET) primarily with respect to lymph-node staging is currently being evaluated in ongoing studies. Due to the high sensitivity of the listed staging modalities in combination with rather low specificity, there is a general tendency towards "over staging", which carries certain risk particularly for potentially operable patients. Consequently the criteria which indicate inoperability (T3, T4, N2, N3 and, in individual cases, M1) have to be confirmed histologically by biopsy employing interventional techniques or even by explorative thoracotomy before definite therapeutic decisions are made.

Biopsy↗
PubMed1998

Toxic spongiform leucoencephalopathy after inhaling heroin vapour.

This is a report of clinical, CT and MRI findings in a patient with toxic spongiform leucoencephalopathy after heroin ingestion. The disease is observed in drug addicts who inhale pre-heated heroin. The clinical onset, which usually occurs some days or even longer after the last heroin consumption, is characterized by a cerebellar syndrome. The cerebellar hemispheres, the cerebellar and cerebral peduncles and the pyramidal tract may be affected. Spongiform demyelination is the morphological substrate of the lesions, which are not contrast enhancing, hypodense on CT and hyperintense on T2-weighted MRI. The frequently perfect symmetry of the affection of functional systems points to a toxic and/or metabolic pathophysiological mechanism.

Administration, Inhalation↗
PubMed1998

Oncology Home Care Service.

The Oncology Home Care Service in Basel provides nursing support to let cancer sufferers choose where they receive palliative care. Most of the cost is borne by the patient's health insurance.

Adolescent↗
PubMed1998

The impact of adding low-dose leucovorin to monthly 5-fluorouracil in advanced colorectal carcinoma: results of a phase III trial. Swiss Group for Clinical Cancer Research (SAKK).

PURPOSE: A wide variety of fluorouracil (FU)-plus-leucovorin (LV) dose schedules are in clinical use for the treatment of advanced colorectal cancer. Only the monthly low-dose LV-plus-FU regimen, as used by the North Central Cancer Treatment Group, has demonstrated a lasting survival benefit as opposed to FU alone (J Clin Oncol 1989; 7: 1407-1417). The Swiss Cancer Group adopted this regimen for a confirmatory phase III trial but used the same dose-intensity of fluorouracil in both treatment arms. PATIENTS AND METHODS: Patients with inoperable or metastatic colorectal cancer were randomized to receive monthly FU 400 mg/m2/day plus LV 20 mg/m2/day as intravenous push daily for five days, or FU alone. RESULTS: Three hundred nine of the 310 patients randomized were eligible and included in the analysis. The objective response rate for patients with measurable disease was 9% with FU alone and 22% with FU-plus-LV (P = 0.0001). The median progression-free survival was 3.9 versus 6.2 months (P = 0.003) and the overall survival 10 versus 12.4 months (P = 0.02). The major prognostic factors for survival were performance status, weight loss, and disease symptoms. WHO > 2 toxicity, consisting of stomatitis (P = 0.001), diarrhea (P = 0.001), and nausea (P = 0.001), was more pronounced for FU-plus-LV, without fatal events. CONCLUSIONS: This is the largest published randomized trial to compare FU-plus-LV to FU alone in advanced colorectal cancer. It confirms the survival benefit obtained from biomodulating monthly FU with low-dose LV. The toxic effects of FU-plus-LV were acceptable to most patients, and they responded well to FU dose reductions. In the absence of an ideal dose-intense FU monotherapy regimen, monthly FU with low-dose LV provides a simple and economical means by which to achieve adequate FU efficacy in the treatment of advanced colorectal cancer.

Adult↗
PubMed1998

Endovascular therapy of brain AVMs prior to radiosurgery.

The purposes of this study were to determine the safety and efficacy of embolization of brain AVMs prior to radiosurgery and to evaluate the total obliteration rate achieved. The brain AVMs of 64 patients were subselectively embolized mainly with NBCA, platinum microcoils and/or PVA. The aim of embolization was the reduction of the target volume and/or the elimination of vascular structures bearing an increased risk of hemorrhage. Presenting symptoms were intracranial hemorrhage in 33 patients, a seizure disorder in 21 patients, and headache in 6 patients. Four AVMs had been detected as an incidental finding. The initial AVM volume was in the range of 0.5 to 84 cc (mean 17 cc). Grading of the AVMs according to the Spetzler-Martin scale showed the following distribution: grade I, 3x; II, 13x; III, 11x; IV, 17x; V, 4x; VI, 16x. A total of 300 endovascular procedures including 47 subselective catheterizations without and 253 with embolization were performed. A size reduction of the AVMs between 10% and 95% (mean 63%, median 70%) was achieved. Neurological symptoms due to treatment complications were transient in 12 patients, of minor clinical significance but permanent in 4 patients. Following radiosurgery, one patient died due to recurrent intracerebral hemorrhage. Three patients are doing well but refused final follow-up angiography. A total of 30 patients is currently within the latency interval after radiosurgery. Radiosurgery failed to obliterate the embolized AVMs in 16 patients. Angiography confirmed complete nidus obliteration in 14 patients. The endovascular treatment of brain AVMs prior to radiosurgery proved safe and effective and may be considered in either high grade or incidental AVMs. AVM obliteration after embolization and radiosurgery is less frequently achieved than after stereotactic irradiation of primarily small AVMs.

Adolescent↗
PubMed1998

Brownian and essential dynamics studies of the HIV-1 integrase catalytic domain.

The three-dimensional structure of the active site region of the enzyme HIV-1 integrase is not unambiguously known. This region includes a flexible peptide loop that cannot be well resolved in crystallographic determinations. Here we present two different computational approaches with different levels of resolution and on different time-scales to understand this flexibility and to analyze the dynamics of this part of the protein. We have used molecular dynamics simulations with an atomic model to simulate the region in a realistic and reliable way for 1 ns. It is found that parts of the loop wind up after 300 ps to extend an existing helix. This indicates that the helix is longer than in the earlier crystal structures that were used as basis for this study. Very recent crystal data confirms this finding, underlining the predictive value of accurate MD simulations. Essential dynamics analysis of the MD trajectory yields an anharmonic motion of this loop. We have supplemented the MD data with a much lower resolution Brownian dynamics simulation of 600 ns length. It provides ideas about the slow-motion dynamics of the loop. It is found that the loop explores a conformational space much larger than in the MD trajectory, leading to a "gating"-like motion with respect to the active site.

Catalytic Domain↗