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O Meyer

Publications and source records attributed to O Meyer.

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

[Sclerosing cholangitis as a complication of Langerhans'cell histiocytosis].

INTRODUCTION: Langerhans'cell histiocytosis is a rare and mainly pediatric disease. Patients with hepatic involvement usually have a disseminated form of the disease, with poor prognosis. Sclerosing cholangitis can occur in 10 to 15% of multivisceral Langerhans'cell histiocytosis. We report the case of a 56-years-old patient who developed sclerosing cholangitis 12 years after the diagnosis of Langerhans'cell histiocytosis. EXEGESIS: A 56-years-old man was admitted because of rapid general health impairment with epigastric pain. He was diagnosed as having Langerhans'cell histiocytosis 12 years ago because of a diabetes insipidus. Lungs were involved and during follow-up vertebral osteocondensation also developed. However, Langerhans'cell histiocytosis was clinically silent at the time of admission, without any treatment. Biologically, cholestasis and inflammation were noted. Digestive radiological investigations (echo-endoscopy, CT-scan, MRI) showed homogenous hepatomegaly and a diffuse infiltration of intra and extrahepatic bile ducts. Liver biopsy yielded the diagnosis of sclerosing cholangitis. Clinical and biological improvement occurred with oral corticosteroids (at 12 months after sclerosing cholangitis diagnosis). CONCLUSION: Sclerosing cholangitis is a potential complication of Langerhans'cell histiocytosis, mainly in its multivisceral form. It can occur at a median of 2 years after diagnosis in children, but occasionally much later in adults, whereas Langerhans'cell histiocytosis seems quiescent. Diagnosis is supported by radiological investigations and liver biopsy. As no drug therapy appears clearly effective, liver transplantation must frequently be considered in these patients.

Abdominal Pain↗
PubMed2003

[Hormonal life in systemic lupus and other connective tissue diseases].

Among connective tissue diseases, systemic lupus erythematosus is the illness that is most concerned by hormonal life events. The sex ratio is 9/1, and symptoms begin mostly during the third decade, sometimes during birth pill contraception or during pregnancy. As soon as systemic lupus is under control of an efficient treatment, pregnancy is no longer contra-indicated. A medical multidisciplinary surveillance is required. Complicated pregnancy concerns mother and baby. Lupus flares are more frequent during the second and third trimesters as well as during the post-partum period. Usually the intensity is moderate. Severe flares concern patients with renal involvement, hypertension and renal insufficiency and are mostly seen in patients with unplanified pregnancy and yet with still active lupus. Foetal death occurs in 10-30% of the cases, depending on the lupus activity and severity (renal lupus). Prematurity remains an important cause of morbidity (30% of live births). Foetal deaths and prematurity are even more frequent if the patient has an antiphospholipid syndrome. Neonatal cutaneous lupus and auriculo-ventricular congenital heart block is infrequent (1% of SLE patients with anti-Ro/SSA antibodies). Among other connective tissue diseases, polymyositis has a very severe obstetrical prognosis for both mother and foetus. Among primary vasculitis, polyarteritis nodosa, as found during pregnancy, can herald a very bad prognosis.

Animals↗
PubMed2003

Endoscopic surgery of the lumbar epidural space (epiduroscopy): results of therapeutic intervention in 93 patients.

Determination and therapy of the underlying pathology in chronic pain syndrome in the lumbar spine is frequently difficult. Minimally invasive and microsurgical techniques may offer advantages. Epiduroscopy is available for visualization of the lumbar epidural space. 93 patients with chronic back-leg pain syndrome were epiduroscopically operated. When findings were appropriate, mechanical instruments and the holmium:YAG laser were applied therapeutically. 45.9 % of these patients presented with positive results in postoperative examination. Pathomorphological processes corresponding to the multifactorial pain processes, which escape detection in modern imaging procedures, can be diagnosed in the epidural space using epiduroscopy Therapeutic intervention is basically possible. However, use is limited due to technical difficulties. Navigation of the endoscope is especially limited in access via the hiatus sacralis.

Adult↗
PubMed2003

Anti-cyclic citrullinated peptide antibodies, IgM and IgA rheumatoid factors in the diagnosis and prognosis of rheumatoid arthritis.

OBJECTIVES: To evaluate the association of anti-cyclic citrullinated peptide (anti-CCP) antibodies with immunoglobulin (Ig) M and IgA rheumatoid factors (RF) in discriminating between rheumatoid arthritis (RA) and other rheumatic diseases, and to determine, in a longitudinal study, whether clinical signs of disease severity are associated with the presence of these autoantibodies at the time of patient inclusion. METHODS: The presence of these three markers was determined in 196 patients with established RA, 239 non-RA controls with various rheumatic diseases (cross-sectional study) and in 27 patients with arthritis of less than 1 yr disease duration who were subsequently followed during about 8 yr (longitudinal study). At the time of follow-up, 21 of these 27 patients had RA. They were further evaluated and several clinical variables were recorded. RESULTS: The specificity was significantly increased (from 82-90% to 98% in the cross-sectional study) when the combination of anti-CCP antibodies with IgA RF or the combination of the three serological markers was used. An association was observed between the presence of the three autoantibodies and clinical signs of disease severity (functional disability, presence of erosions and absence of clinical remission). CONCLUSIONS: The presence either of anti-CCP antibodies and IgA RF or of the three markers appears to be useful in the diagnosis of RA. Their association with clinical signs of disease severity at the time of patient inclusion suggests their potential usefulness as markers for prognosis.

Adult↗
PubMed2003

Anticitrullinated protein/peptide antibody assays in early rheumatoid arthritis for predicting five year radiographic damage.

OBJECTIVE: To study the value of antibodies to citrullinated proteins/peptides for predicting joint outcomes in patients with recent onset rheumatoid arthritis (RA). METHODS: 191 patients with RA onset within the past year were followed up prospectively for five years. Serum samples obtained from 145 patients at baseline before disease modifying antirheumatic drug treatment were examined using three anticitrullinated protein/peptide antibody assays: antiperinuclear factor (APF) by indirect immunofluorescence (IIF), antikeratin antibodies (AKA) by IIF, and anti-cyclic citrullinated peptide (CCP) antibodies by enzyme linked immunosorbent assay (ELISA). Radiographs of the hands and feet taken at baseline and after three and five years were evaluated using Sharp scores modified by van der Heijde. RESULTS: Anti-CCP ELISA was positive in 58.9% of patients. APF/anti-CCP agreement was 77%. The likelihood of a total Sharp score increase after five years was significantly greater among patients with anti-CCP antibodies (67%; odds ratio (OR) 2.5; 95% confidence interval (95% CI) 1.2 to 5.0) or APF (57%; OR 2.4; 95% CI 1.2 to 4.9) but not rheumatoid factor (RF; OR 0.7; 95% CI 0.3 to 1.5). Mean values for radiographic damage, erosion, and joint narrowing scores at the three times were significantly higher in patients with anti-CCP or APF than in those without. AKA did not significantly predict radiographic damage. In separate analyses of patients with and without RF, anti-CCP or APF was better than RF for predicting total joint damage and joint damage progression after five years. CONCLUSION: Antibodies to citrullinated proteins/peptides determined early in the course of RA by APF IIF or anti-CCP ELISA are good predictors of radiographic joint damage. Further studies of clinical, laboratory, and genetic parameters are needed to improve RA outcome prediction in clinical practice.

Adult↗
PubMed2003

Assessment of vascular involvement.

Our objective was to identify a core set of variables for the assessment of vascular involvement in scleroderma that is simple, reproducible, and reflects the presence of vascular disease in SSc. To do so we carried out an extensive literature review of published studies relating to the assessment of vascular involvement in SSc, i.e. studies dealing with clinical parameters, functional vascular studies, cold presser testing, nailfold capillary microscopy and circulating vascular markers. After extensive review of published studies and critical assessment of proposed vascular parameters, the subcommittee endorsed what it considers to be the minimal requirements for the documentation of vascular involvement in SSc. The core set variables include two parameters: Raynaud's phenomenon and digital ulcers. This set is simple, reproducible and should be included in the assessment of SSc patients in clinical investigational studies. The subcommittee also however recognizes that there exists a promising set of vascular variable that still needs further investigation.

Blood Vessels↗
PubMed2002

[Does intraoperative hyperventilation improve neurological functions of older patients after general anaesthesia?].

UNLABELLED: The purpose of the study was to investigate the effect of intraoperative hyperventilation on postoperative cognitive functions. METHODS: A total of 120 patients (60 older and 60 younger than 65 years old) were allocated randomly to group I "hyperventilation" (p(et)CO(2)=30 mmHg) or group II "normoventilation" (p(et)CO(2)=45 mmHg). Before the operation and on days 1, 3 and 6 after the operation, a battery of neuropsychological tests was performed (concentration endurance test d2, number connection test, digit symbol test). A decline of 20% in at least one test was regarded as postoperative cognitive deficit (POCD). Anaesthesia was maintained with isoflurane in nitrous oxide/oxygen supplemented with fentanyl. RESULTS: In all patients pooled, POCD was present in 26 patients (22%). In patients older than 65 years, POCD was present in 3 cases after hyperventilation and 13 cases after normoventilation ( p<0.01). In younger subjects, 5 cases of POCD were diagnosed in each ventilation group. Furthermore, POCD was more severely pronounced in older patients after normoventilation. CONCLUSION: In older patients, POCD occurred more frequently after intraoperative normoventilation. We assume that a reduced amount of noxious substances reach the brain after hyperventilation, because hyperventilation reduces the cerebral blood flow.

Aged↗
PubMed2002

Serum concentration of S-100 protein in assessment of cognitive dysfunction after general anesthesia in different types of surgery.

BACKGROUND: S-100 protein serum concentration (S-100) serves as a marker of cerebral ischemia in cardiac surgery, head injury and stroke. In these circumstances S-100 corresponds well with the results of neuropsychological tests. The aim of the present study was to investigate the value of S-100 and neuron specific enolase (NSE) in reflecting postoperative cognitive deficit (POCD) after general surgical procedures. METHODS: One hundred and twenty patients undergoing vascular, trauma, urological or abdominal surgery were investigated. Serum values of S-100 and NSE were determined preoperatively and 0.5, 4, 18 and 36 h postoperatively. Neuropsychological tests for detecting POCD were performed preoperatively and on day 1, 3, and 6 after the operation. A decline of more than 10% in neuropsychological test results was regarded as POCD. Furthermore, we retrospectively compared the S-100 in patients with and without POCD in different types of surgery. RESULTS: According to our definition, forty-eight patients had POCD (95% confidence interval: 37.5-58.5). These patients showed higher serum concentrations of S-100 (median 024 ng/ml; range 0.01-3.3 ng/ml) compared with those without POCD (n=69; median 0.14 ng/ml; range 0-1.34 ng/ml) 30 min postoperatively (P=0.01). Neuron specific enolase was unchanged during the course of the study. Differences of S-100 in patients with and without POCD were found in abdominal and vascular surgery but not in urological surgery. CONCLUSION: When all patients are pooled, S-100 appears to be suitable in the assessment of incidence, course and outcome of cognitive deficits. We suspect that in some surgical procedures, such as urological surgery, S-100 appears to be of limited value in detecting POCD. Neuron specific enolase did not reflect neuropsychological dysfunction after noncardiac surgery.

Adolescent↗
PubMed2002

[The abbreviated mental test in a German version for detection of postoperative delirium].

OBJECTIVES: Delirium is the most common acute organic psychosis postoperatively, and occurs more frequently in the elderly than anticipated. The abbreviated mental test (AMT) is a widely used cognitive test in Great Britain. The present study assessed the AMT in a German version for diagnosis of postoperative delirium. METHODS: 40 patients (older than 65 years), scheduled for total knee or hip replacement, were tested repeatedly for delirium according to the ICD-10. These patients were investigated with the AMT simultaneously by a second investigator. RESULTS: Delirium was present in four orthopaedic patients (10 %) and was diagnosed correctly in these patients by the AMT. All but one patient without delirium showed no deterioriation in AMT score. CONCLUSION: As in Great Britain, the AMT in its German version is useful in diagnosing delirium. We recommend the use of the AMT preoperatively in elderly patients at risk for delirium.

Aged↗
PubMed2002

Application of holmium:YAG laser in epiduroscopy: extended practicabilities in the treatment of chronic back pain syndrome.

OBJECTIVE: Minimally invasive and endoscopic techniques offer advantages in the treatment of chronic back pain syndrome and may provide for expanded indications and visualization. Epiduroscopy for the visualization of the epidural space still is burdened with technical problems. The mechanical instruments now available, coupled with the narrow working canal, result in marked limitations. The aim of this study was to assess the possibilities and technical requisites for the use of the holmium:YAG laser in lumbar epiduroscopy. BACKGROUND DATA: Epiduroscopy has been used for visualization of the lumbar epidural space since the 1930s. Studies have been performed to evaluate the effects and possibilities of epiduroscopy in chronic back pain. Most of them only describe the anatomical aspects. MATERIALS AND METHODS: Forty-seven patients were epiduroscopied and treated, for findings of corresponding epidural adhesions, with the holmium:YAG laser. The examinations concentrated on the general applicability of the holmium:YAG laser in epiduroscopy and the technical parameters necessary for this procedure. The clinical evaluation of therapy was made prospectively in comparison with the preoperative status and compared to already recorded groups in previous studies. RESULTS: Bending behavior without negative impact of the epiduroscope was only attained with laser fibers less than 300 microm, so a fiber with a diameter of 265 microm was used as the standard. The minimum energy output of the laser required for an adequate ablative effect was 0.8 J at a frequency of 8 Hz. The total energy output was 0.256-1.4 kJ. Complications did not occur intraoperatively nor following the procedure. The follow-up examinations showed no deterioration of the complaints in any patient. There was no occurrence of relevant laser-related edemas or adhesions. The proportion of painful conditions that could be positively influenced corresponded to that in a control group treated only by mechanical means. CONCLUSION: The results show that the holmium:YAG laser considerably expands therapeutic possibilities and aids in solving the technical problems of epiduroscopy. No negative effects occurred when the laser is used.

Adult↗
PubMed2002

An eight year prospective study of outcome prediction by antiperinuclear factor and antikeratin antibodies at onset of rheumatoid arthritis.

OBJECTIVES: Antikeratin antibodies (AKA) and antiperinuclear factor (APF) are specific antibodies found very early in rheumatoid arthritis (RA). The objective of this eight year follow up study was to assess the value of early AKA and APF assays in predicting functional disability and cartilage damage. METHOD: In 2000, 64 patients tested for AKA and APF (antifilaggrin antibodies) between 1990 and 1993 during evaluation of early symmetric oligoarthritis or polyarthritis (suspected RA) were invited to participate in this non-concurrent cohort study. The Health Assessment Questionnaire (HAQ) score, disease activity score (DAS), and Larsen radiographic score were the primary evaluation criteria. RESULTS: Twenty nine patients were re-evaluated. Clinical and laboratory data obtained in 1993 were similar in this group and in the 35 other patients. Twenty five patients had received a diagnosis of RA. Nine (31%) were rheumatoid factor (RF) positive, nine (31%) were AKA positive, and six (21%) were APF positive during the first year of the disease. APF was correlated with the Larsen score (p=0.011) and DAS (p=0.035) evaluated after a mean disease duration of 8.55 years. All APF positive patients had erosive disease. AKA was correlated with the DAS (p=0.035). CONCLUSION: The presence of AKA or APF early in the course of RA was associated with the DAS or Larsen score eight years later. The number of patients was small, but the findings confirmed those of studies with shorter follow ups. Antifilaggrin antibodies should be included in the initial investigation of patients with RA and, when positive, should alert to a high risk of poor outcomes.

Antibodies, Antinuclear↗
PubMed2002

Oculomotor palsy in six patients with systemic lupus erythematosus. A possible role of antiphospholipid syndrome.

The objective of this study was to describe clinical, laboratory, and radiological features in systemic lupus erythematosus (SLE) patients with oculomotor palsy (OMP). Among a cohort of 750 SLE patients receiving follow-up at our unit between 1985 and 2000, all patients with OMP were studied. Clinical and laboratory data were recorded, as well as cerebral magnetic resonance imaging (MRI) findings where available. Immunological tests included tests for presence and specificity of antinuclear and antiphospholipid antibodies. Six patients had OMP, which occurred within the first 3 years in two patients and after more than 20 years in two patients. Four patients had focal neuropsychiatric SLE (NPSLE) manifestations and two had diffuse neurological involvement. The four patients with focal NPSLE were either anticardiolipin- or lupus anticoagulant-positive. Cerebral fluid was abnormal in two of four patients who had this test. In four of the six patients, cerebral MRI showed evidence of vasculopathy. The therapeutic regimens varied, although all six patients initially received high-dose corticosteroids. OMP resolved or improved significantly in all six patients. OMP in SLE occurs in a broad spectrum of clinical situations but is an infrequent manifestation of NPSLE. This case series, together with literature review data, suggests various pathophysiological mechanisms in patients with focal or diffuse neurological symptoms. In patients with focal NPSLE, a possible cause of OMP is microthrombosis associated with presence of antiphospholipid antibodies.

Adult↗
PubMed2001

Crystal structure of a carbon monoxide dehydrogenase reveals a [Ni-4Fe-5S] cluster.

The homodimeric nickel-containing CO dehydrogenase from the anaerobic bacterium Carboxydothermus hydrogenoformans catalyzes the oxidation of CO to CO2. A crystal structure of the reduced enzyme has been solved at 1.6 angstrom resolution. This structure represents the prototype for Ni-containing CO dehydrogenases from anaerobic bacteria and archaea. It contains five metal clusters of which clusters B, B', and a subunit-bridging, surface-exposed cluster D are cubane-type [4Fe-4S] clusters. The active-site clusters C and C' are novel, asymmetric [Ni-4Fe-5S] clusters. Their integral Ni ion, which is the likely site of CO oxidation, is coordinated by four sulfur ligands with square planar geometry.

Aldehyde Oxidoreductases↗
PubMed2001

The influence of simple sugars and starch given during pre- or post-initiation on aberrant crypt foci in rat colon.

The aim of the present study was to investigate the enhancing effect of dietary sugar on the development of aberrant crypt foci (ACF) in male F344 rats initiated with azoxymethane (AOM). The potential role of sugar as either a co-initiator or a promoter was investigated by giving diets high in sucrose and dextrin (61%) during either the pre-initiation, the initiation, and/or the post-initiation stage of the ACF development. The colonic cell proliferation, activity of colonic phase II enzymes, and a biomarker of lipid peroxidation were additionally examined in order to obtain information on the specific mechanisms involved in the suggested effect of sucrose and dextrin on ACF development. The number of large sized and the total number of ACF were significantly increased by feeding sucrose and dextrin in the post-initiation period. No positive association between colonic cell proliferation and ACF was seen. The level of oxidative stress in the cytosol from the proximal colon and colonic glutathione transferase and quinone reductase was not affected by the sugar treatments. The overall results from this study show that sucrose and dextrin enhance the number of preneoplastic lesions in AOM-initiated rats, and act primarily as promoters in the development of ACF.

Animals↗
PubMed2001

A new family of chelating diphosphines with a transition metal stereocenter in the backbone: novel applications of "chiral-at-rhenium" complexes in rhodium-catalyzed enantioselective alkene hydrogenations.

The title compounds are accessed by sequences starting with racemic and enantiomerically pure [(eta5-C5H5)Re(NO)(PPh3)(CH3)]. Reactions with chlorobenzene/HBF4, PPh2H, and tBuOK give the phosphido complex [(eta5-C5H5)Re(NO)(PPh3)(PPh2)] (3). Reactions with Ph3C+ BF4-, PPh2H, and tBuOK give the methylene homologue [(eta5-C5H5)Re(NO)(PPh3)(CH2PPh2)] (9). Treatment of 3 or 9 with nBuLi or tBuLi and then PPh3Cl gives the diphosphido systems [(eta5-C5H4PPh2)Re(NO)(PPh3)((CH2)nPPh2)] (n = 0/1, 5/11). Reactions of 5 and 11 with [Rh(NBD)Cl]2/AgPF6 (NBD = norbornadiene) give the rhenium/rhodium chelate complexes [(eta5-C5H4PPh2)Re(NO)(PPh3)((mu-CH2)nPPh2)Rh(NBD)]+ PF6- (n = 0/1, 6+/12+ PF6-; 30-32% overall from commercial Re2(CO)10). The crystal structures of 6+ PF6- and 12+ PF6- are compared to those of 3 and 9, and other rhodium complexes of chelating bis(diphenylphosphines). The chiral pockets defined by the PPh2 groups show unusual features. Four alkenes of the type (Z)-RCH=C(NHCOCH3)CO2R' are treated with H2 (1 atm) and (R)-6+ PF6- or (S)-12+ PF6- (0.5 mol%) in THF at room temperature. Protected amino acids are obtained in 70-98% yields and 93-82% ee [(R)-6- PF6-] or 72-60% ee [(S)-12+ PF6-]. Pressure and temperature effects are defined, and turnover numbers of > 1600 are realized.

Journal Article↗
PubMed2001

The configurational stability of an enantioenriched alpha-thiobenzyllithium derivative and the stereochemical course of its electrophilic substitution reactions; synthesis of enantiomerically pure, tertiary benzylic thiols.

The lithium compound (S)-7, formed by deprotonation of the (S)-S-1-phenylethyl thiocarbamate (S)-10, is configurationally stable at -70 degrees C. Even at elevated temperatures it racemizes only very slowly. It represents the first essentially enantiopure alpha-thiocarbanion derivative and can be utilized in asymmetric synthesis. Most electrophiles (except proton acids) add to (S)-7 with complete stereoinversion. Cleavage of the substitution products leads to practically enantiopure, tertiary 1-phenylalkanethiols.

Journal Article↗