PubMed Health⌕ Search

Biomedical subjects

M Jäger

Publications and source records attributed to M Jäger.

At least 37 records · Page 2Linked to original sources
PubMed2004

[Comparative analyses of the reliability of automatic external defibrillators].

Automatic external defibrillators are gaining increasing acceptance. Last year 6000 devices were installed in Germany. Since the average user has only limited medical knowledge, high demands have to be made on the automatic ECG diagnosis (fibrillation detection). Within the framework of this study a fully automatic test system that permits an objective comparison of the performance of the various devices available on the market was constructed. Older devices in particular do not always meet the requirements defined by international standards with regard to sensitivity and specificity. In addition, company philosophy appears to differ in terms of the preferential emphasis on sensitivity or specificity. Purchasers of such devices need take these findings into consideration.

Arrhythmias, Cardiac↗
PubMed2004

[Growth behaviour of human mononuclear cells derived from bone marrow and cord blood on a collagen carrier for osteogenic regeneration].

UNLABELLED: We investigated the biocompatibility and osteogenetic potency of a porcine collagen I/III carrier in a human bone marrow and cord blood cell culture system. METHODS: Human mesenchymal mononuclear cells were isolated from cord blood and iliac crest bone marrow and cultivated in various cell densities on a semipermeable porcine collagen I/III carrier. After 14 days of in vitro cultivation both cultures were subjected to osteogenic stimulation by dexamethasone, ascorbic acid and beta-glycerol phosphate (DAG) until day 40. Semiquantitative immunochemical evaluation based on osteoblastic and progenitor cell markers was then done. RESULTS: With regard to the minimal local cell density required for growth and osteogenic differentiation, cord blood derived progenitor cells showed lower tolerance in comparison with bone marrow derived cells. For both cell culture systems three-dimensional growth and calcification within the collagen fibres were seen after osteogenic stimulation. CONCLUSION: Human cord blood and bone marrow derived mesenchymal stem cell are capable of differentiating into osteoblasts after incubation with a collagen I/III biomaterial.

Animals↗
PubMed2003

[Diagnostic shifts of functional psychoses in the transition from ICD-9 to ICD-10].

In order to identify diagnostic changes caused by the transition from ICD-9 to ICD-10, in a sample of 218 first hospitalised patients from the years 1980 and 1981, ICD-9 diagnoses were compared with ICD-10 diagnoses. For this comparison, functional psychoses were classified into five main diagnostic groups. Results showed a decreased frequency of the diagnostic groups schizophrenia, schizoaffective psychoses, and paranoid psychoses and an increased frequency of the diagnostic groups acute psychoses and affective psychoses. With the exception of acute psychoses and schizoaffective psychoses, a high agreement between ICD-9 and ICD-10 diagnoses was found, and the Kappa value was 0.70. With regard to the homogeneity of psychopathological symptoms, ICD-10 diagnoses showed no improvement over ICD-9 diagnoses. Nevertheless, ICD-10 diagnoses have gained in predictive validity because schizophrenia was further narrowed to cases with a more unfavourable outcome.

Adult↗
PubMed2003

[Negative symptoms of schizophrenic patients from the perspective of psychiatrists, patients themselves and their relatives].

Clinical experience shows that negative symptoms are affected by environmental factors. Thus, different assessors with different information about patient behavior in different environments may come to different findings of negative symptoms. In this regard, the present study evaluates to what extent the assessment of negative symptoms by schizophrenic inpatients and their relatives compares to interview-based assessments by experts. Therefore, 33 schizophrenic patients were rated by patients themselves, their relatives, and psychiatrists. Negative symptoms were assessed with comparable assessment scales using the modified version of the Scale for the Assessment of Negative Symptoms (SANS) for patients or relatives and the original SANS for psychiatrists. Analyses revealed that the total SANS summary scores as rated by patients and relatives were comparable to scores rated by psychiatrists. Scores on SANS subscales of "alogia" and "attention deficits" differed significantly among the three ratings, while psychiatrists rated the patients' impairments as lower than did the patients themselves or their relatives. These findings indicate that patients' and relatives' ratings could be used to reduce information variance and improve the validity of interview-based, assessed negative symptoms.

Adult↗
PubMed2003

Comprehensive biocompatibility testing of a new PMMA-hA bone cement versus conventional PMMA cement in vitro.

For more than 50 years PMMA bone cements have been used in orthopaedic surgery. In this study attempts were made to show whether cultured human bone marrow cells (HBMC) show an osteogenetic response resulting in new bone formation, production of extracellular matrix (ECM) and cell differentiation when they were cultured onto polymerized polymethylmethacrylate (PMMA)-hydroxyapatite (HA), conventional PMMA bone cement being taken as reference. Biocompatibility parameters were collagen-I and -II synthesis, the detection of the osteoblast markers alkaline phosphatase (ALP) and osteocalcin, the number of adherent cells and the cytodifferentiation of immunocompetent cells. Cement surface structure, HA stability in culture medium and chemical element analysis of specimens were considered. Fresh marrow cells were obtained from the human femora during hip replacement. Incubation time was up to ten weeks. We used atomic forced microscopy (AFM) and scanning electron microscopy (SEM) for cement specimen analysis. Fluorescent activated cell sorter (FACS), immunohistochemical staining. SEM and light microscopy (LM) served us to judge the cellular morphology. Products of the extracellular matrix were analyzed by protein dot blot analysis, SEM energy dispersive X-ray analysis (SEM-EDX) and Ca2+/PO(4)3- detection. HA particles increased the osteogenetic potential of PMMA bone cement regarding the cellular production of collagen, alkaline phosphatase (AP), the number of osteoblasts and the cellular differentiation pattern in vitro. Both tested cements showed good biocompatibility in a human long-term bone marrow cell-culture system.

Bone Cements↗
PubMed2003

Cystoid macular edema associated with latanoprost therapy in a pseudophakic vitrectomized patient after removal of silicone oil endotamponade.

PURPOSE: To describe the occurrence of cystoid macular edema in a pseudophakic vitrectomized patient following use of latanoprost (0.005%). METHODS: A 58-year-old patient underwent routine cataract surgery with posterior chamber lens implantation complicated by rhegmatogenous retinal detachment three months later. A pars plana vitrectomy was performed with silicone oil endotamponade which was removed six months later. Five months after oil removal, the patient presented with secondary open-angle glaucoma treated with latanoprost 0.005% eye drops once daily. RESULTS: Two weeks after initiation of latanoprost treatment, visual acuity dropped from 0.8 to 0.3 due to cystoid macular edema confirmed by fluorescein angiography. After discontinuing latanoprost therapy and with topical corticosteroid treatment, cystoid macular edema slowly resolved, and within 6 months, visual acuity improved to 0.8. CONCLUSIONS: Despite its marked ocular hypotensive effect, latanoprost should be carefully used in patients after uncomplicated cataract surgery if the vitreous body was removed by pars piana vitrectomy.

Antihypertensive Agents↗
PubMed2003

Influence of different culture solutions on osteoblastic differentiation in cord blood and bone marrow derived progenitor cells.

Mesenchymal progenitor cells derived from cord blood (unrestringated somatic stem cells, USSC) and bone marrow (mesenchymal stem cells, MSC) are able to differentiate under defined culture conditions into at least bone, cartilage, adipose and muscle cells in vitro. The culture media and other in vitro conditions influence the osteogenic differentiation potency of both cell types. To increase and expand the number of osteoblasts in vitro an optimization of culture conditions is required. The aim of this study was to evaluate different culture media toward their osteogenic promoting capacity on human USSCs and MSCs in vitro. Immunohistochemical stainings against osteonectin (ON), osteopontin (OP) served as markers for an osteoblastic differentiation. Cellular morphology was analysed by light microscopy technique. We found significant differences between bone marrow and cord blood derived stem cells towards an osteoblastic differentiation. Considering the number of osteoblasts MesenCult seems to have advantages in bone marrow progenitor cells, whereas low glucose DMEM and HAMS-F12 promoted an osteoblastic differentiation in cord blood derived cells more than other tested media.

Cell Culture Techniques↗
PubMed2002

[Acute low back pain with progressive sensorimotor paralysis. Differential diagnosis and therapy of acute decompression disease].

HISTORY AND CLINICAL FINDINGS: A 38-year-old man presented with acute low back pain and paraesthesia in dermatome S1. 4 hours before onset of symptoms he had finished the last of three scuba dives with a maximum depth of 30 m and a total diving time of 3 hours. No alcoholic beverages were taken during or before diving. The patient was complaining of local pain in the thoracic and lumbar spine and showed a 3/5 weakness of the big toe and impaired sensitivity in the S1 dermatome. 90 minutes later the patient developed a hemiparesis of the right side including hypaesthesia and additional meningism (stiff neck). INVESTIGATIONS: The X-rays of the thoracic and lumbar spine in two standard planes, cerebrospinal fluid examination, a cranial spiral-computer tomographie (CCT) and laboratory investigations showed no pathologic values. DIAGNOSIS: Acute decompression sickness (DCS) type II. TREATMENT AND COURSE: The patient received an intravenous infusion, antiinflammatory prophylaxis with dexamethasone and an immediate submission to hyperbaric oxygenation therapy. Complete recovery of neurological symptoms appeared after 4 decompression sessions in a hyperbaric chamber. CONCLUSIONS: In patients presenting low back pain as common symptoms the differential diagnosis needs to be worked out and DCS should be included especially if progressive neurologic deficits are present. Only emergency hyperbaric oxygen therapy can compromise a sufficient therapy of these patients.

Acute Disease↗
PubMed2002

Are bipolar I depressive patients less responsive to treatment with antidepressants than unipolar depressive patients? Results from a case control study.

The increasing evidence that bipolar and unipolar affective disorders have different biological etiologies and courses of illness has been associated with an intensifying interest in specific treatment regimens for both disorders during the last decade. In this context, the question arose whether antidepressants exert similar efficacy in the acute treatment of bipolar compared to unipolar depression. Although the clinical impression does not indicate substantial differences in the efficacy of antidepressants between these groups of patients, empirical databases concerning this topic are rare. The present study compared the efficacy of antidepressants in 50 unipolar and 50 bipolar depressed inpatients (ICD-9 criteria) under naturalistic treatment conditions. Both groups of patients were matched for age, gender and duration of illness. Clinical assessments of status at the time of admission and at discharge were used to rate response to antidepressant treatment. Analyses of the data revealed that both groups of patients needed the same time for treatment response and did not show any significant differences in outcome measures at discharge. These findings do not concur with the hypothesis formulated by some experts in the field of affective disorders that antidepressants are less effective in the acute treatment of bipolar depressed patients compared to unipolar depressed patients.

Antidepressive Agents↗
PubMed2002

Morbidity and mortality associated with pancreatogastrostomy and pancreatojejunostomy following partial pancreatoduodenectomy.

BACKGROUND: The pancreatic anastomosis is still the Achilles heel in partial pancreatoduodenectomy (PPD). METHODS: This study describes retrospectively a series of 441 patients who underwent standard or extended PPD and reconstruction by either pancreatogastrostomy or pancreatojejunostomy over a period of 13 years (1988-2000). RESULTS: Reconstruction of the pancreatic remnant was achieved by pancreatogastrostomy in 250 patients (56.7 per cent) and by pancreatojejunostomy in 191 patients (43.3 per cent). The leakage rate of the pancreatic anastomosis was 2.8 per cent after pancreatogastrostomy versus 12.6 per cent after pancreatojejunostomy (P < 0.001), whereas other surgical complications (bile leakage, haemorrhage, pancreatitis) were identical in the two groups. The leakage rate after standard PPD with or without vascular reconstruction was 2.0 per cent (four of 205 patients) after pancreatogastrostomy and 11.5 per cent (18 of 156) after pancreatojejunostomy (P < 0.001); following extended PPD it was 6.7 per cent (three of 45) after pancreatogastrostomy and 17.1 per cent (six of 35) after pancreatojejunostomy. The mortality rate due to leakage was 1.6 per cent (four of 250 patients) after pancreatogastrostomy versus 5.2 per cent (ten of 191) after pancreatojejunostomy (P = 0.037). CONCLUSION: Pancreatogastrostomy is a safe and reliable method of reconstruction after PPD that may be associated with a lower leakage and mortality rate than pancreatojejunostomy.

Adolescent↗
PubMed2002

Neuroleptic malignant syndrome due to atypical neuroleptics: three episodes in one patient.

Neuroleptic malignant syndrome (NMS) is a rare, but potentially lethal complication of antipsychotic medication. The risk of developing NMS under atypical neuroleptics seems lower than under typical neuroleptics. However, the use of atypical neuroleptics in modern psychopharmacotherapy is increasing, so the incidence of NMS under these drugs may also increase. Here, we will describe three episodes of NMS that fulfilled the DSM-IV criteria for NMS (APA, 1994). The epivodes of NMS occured under treatment with clozapine, risperidone, and amisulpride. These episodes had some atypical features that will be discussed with regard to the pathophysiological mechanisms leading to NMS.

Amisulpride↗
PubMed2002

A new technique for the surgical management of deformities in the growing spine.

The Luque procedure was developed to correct the deformity without the need of bracing and maintaining that correction with growth. However many authors are disappointed by their results and the complications which appear in the management of infantile scoliosis with Luque trolley alone. Besides failed implants, pseudarthrosis, modest spinal growth and protuberant rods and wires, the major problem of the Luque systems is the high incidence of loss of correction by postoperative rotation. Therefore a new application technique is recommended. A standard posterior extraperiostal approach is chosen. Sublaminar titanium cables are passed at each level except the caudal lamina. Then the rods are precontoured in shape of the planed curve correction. We use a low profile titanium instrumentation with 5.0 mm diameter rods and 4.2 mm pedicle screws. In contrast to the conventional use of two antiparallel "L"-rods we recommend the use of one reversed "U"-rod securing the laminae with sublaminar titanium cables of the upper end vertebrae. For fixation of the lower spine a dual-opening pedicle screw system is used. Using a holding forceps the distal rods are introduced and fixed into the side opening of the screws then secured by sublaminar wires. In addition both single rods are stabilized by a low profile cross link bar. This technique allows to correct pelvic obliquity and a stable anchorage of two screws reduces risk of postoperatively rotation or caudal rod slippage due to gravity forces.

Adolescent↗
PubMed2002

[Fracture analysis of a ceramic liner. Is in hip endoprosthesis replacement of ceramic on ceramic components with only one of the corresponding partners justified?].

The good biomechanical and tribological properties, together with the excellent biocompatibility, of ceramic-on-ceramic components, make them a preferential choice for total hip replacement surgery, at least in Europe. We report on a man admitted as an outpatient with painless grating in the hip one year after replacement of a ceramic femoral head, but not of the ceramic inlay. Clinical and radiological findings were indicative of a broken liner. This was confirmed during revision surgery, during which it was replaced by a polyethylene inlay; although the ceramic head appeared intact, it was replaced by a metal head. Inspection of the surface of the broken liner in the scanning electron microscope (SEM) revealed signs of material failure. We recommend careful inspection of ceramic-on-ceramic articulating components during total hip revision surgery and if there is any uncertainty, replacement of both so as to avoid premature failure.

Aged↗
PubMed2001

Treatment of congenital spondyloptosis in an 18-month-old patient with a 10-year follow-up.

STUDY DESIGN: Case report. OBJECTIVES: To present the case of a patient with congenital spondyloptosis treated and followed over 10 years. SUMMARY OF BACKGROUND DATA: The surgical management of spondyloptosis in children is variably reported in the literature. Some authors propose that posterior fusion in situ is a safe and reliable procedure, whereas others suggest that reduction of the slipped vertebra may prevent some of the adverse sequelae of in situ fusion, which include nonunion, bending of the fusion mass, and persistent lumbosacral deformity. Many investigators advocate a combined anterior and posterior fusion using instrumentation. METHODS: At the time of the first symptoms an 18-month-old boy with congenital spondyloptosis of L5-S1 was referred to the authors' institution. Because of the progression of pain, neurologic disturbance, mild foot deformity, muscle contractures, and lumbosacral kyphosis, surgical intervention was undertaken. Operative intervention began with a resection of the L5 lamina and wide bilateral L5 nerve root decompression. This was followed by anterior subtotal resection of L5 and interbody bone graft of the morcelized vertebral body for fusion from L5 to S1. The next step was reduction of the spondyloptosis and stabilization by posterior instrumentation L2-S1 with a sacral Cotrel-agraffe device. RESULTS: The procedure achieved almost complete reduction of the spondyloptosis with near-normal restoration of lumbar lordosis allowing more physiologic lumbar spinal biomechanics. There were no neurologic complications. After surgery there was no suggestion of back pain or gait disturbance and no progression of any deformity. CONCLUSION: In the treatment of severe congenital spondylolisthesis a staged procedure of decompression, reduction, and instrumented fusion is recommended for those cases in which intervention is indicated.

Decompression, Surgical↗
PubMed2001

The folding mechanism of a beta-sheet: the WW domain.

The folding thermodynamics and kinetics of the Pin WW domain, a three-stranded antiparallel beta-sheet, have been characterized extensively. Folding and activation free energies were determined as a function of temperature for 16 mutants, which sample all strands and turns of the molecule. The mutational phi value (Phi(m)) diagram is a smooth function of sequence, indicating a prevalence of local interactions in the transition state (TS). At 37 degrees C, the diagram has a single pronounced maximum at turn 1: the rate-limiting step during folding is the formation of loop 1. In contrast, key residues for thermodynamic stability are located in the strand hydrophobic clusters, indicating that factors contributing to protein stability and folding kinetics are not correlated. The location of the TS along the entropic reaction coordinate Phi(T), obtained by temperature-tuning the kinetics, reveals that sufficiently destabilizing mutants in loop 2 or in the Leu7-Trp11-Tyr24-Pro37 hydrophobic cluster can cause a switch to a late TS. Phi(m) analysis is usually applied "perturbatively" (methyl truncation), but with Phi(T) to quantitatively assess TS shifts along a reaction coordinate, more severe mutations can be used to probe regions of the free energy surface beyond the TS.

Amino Acid Sequence↗
PubMed2001

Incorporating beta-turns and a turn mimetic out of context in loop 1 of the WW domain affords cooperatively folded beta-sheets.

To probe the conformational requirements of loop 1 in the Pin1 WW domain, the residues at the i + 2 and i + 3 positions of a beta-turn within this loop were replaced by dPro-Gly and Asn-Gly, which are known to prefer the conformations required at the i + 1 and i + 2 positions of type II' and type I' beta-turns. Conformational specificity or lack thereof was further examined by incorporating into the i + 2 and i + 3 positions a non-alpha-amino acid-based beta-turn mimetic (4-(2'-aminoethyl)-6-dibenzofuran propionic acid residue, 1), which was designed to replace the i + 1 and i + 2 positions of beta-turns. All these Pin WW variants are monomeric and folded as discerned by analytical ultracentrifugation, NMR, and CD. They exhibit cooperative two-state transitions and display thermodynamic stability within 0.5 kcal/mol of the wild-type WW domain, demonstrating that the acquisition of native structure and stability does not require a specific sequence and, by extension, conformation within loop 1. However, it could be that these loop 1 mutations alter the kinetics of antiparallel beta-sheet folding, which will be addressed by subsequent kinetic studies.

Amino Acid Sequence↗
PubMed2001

REM sleep behavior disorder in sleep-disordered patients with versus without Parkinson's disease: is there a need for polysomnography?

We reviewed the polysomnograms (PSGs) of 292 consecutive patients with sleep disorders (Parkinson's disease (PD), n=19, other sleep disorders, n=273) to investigate the sensitivity and specificity of the clinical diagnosis of rapid eye movement behavior disorder (RBD) compared with polysomnographic diagnosis. Patients with dementia, multiple system atrophy, or any other neurodegenerative disease were excluded. RBD was diagnosed clinically if the minimal criteria, according to the guidelines given in the International Sleep Disorders Classification, were fulfilled. The following PSG criteria were required for diagnosis of RBD: REM sleep without muscle atonia seen in PSG associated with motor behavior visible in the PSG-synchronized videotape. Nine of nineteen PD patients (47%) had RBD. RBD occurred in only four patients without PD (1.8%). The sensitivity of specialized interviews for identifying RBD clinically was good in non-PD patients (sensitivity: 100%, specificity: 99.6%). However, the sensitivity was poor (33%) with a specificity of 90%, in patients with PD. We conclude that the diagnosis of RBD in patients with PD requires PSG, whereas interviews are sufficient for diagnosing RBD in non-PD patients.

Aged↗