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S Schreiber

Publications and source records attributed to S Schreiber.

At least 91 records · Page 5Linked to original sources
PubMed2001

Use of anti-tumour necrosis factor agents in inflammatory bowel disease. European guidelines for 2001-2003.

The introduction of novel anti-tumor necrosis factor (TNF) agents has not only led to impressive new therapeutic opportunities but also resulted in uncertainty regarding their optimal use and possible side effects. Guidelines are presented here for the use of anti-TNF agents in gastrointestinal disorders. Experts were chosen from different European countries by an algorithm to avoid bias. An expert consensus on guidelines was established using a two-stage procedure of systematic Medline and abstract search for evidence and a qualifying meeting to derive recommendations. Detailed guidelines were developed for the use and the future clinical development of anti-TNF agents in inflammatory bowel disease. Grading of available evidence and grading of recommendations were performed according to AHCPR guidelines. At present infliximab is the only registered agent for Crohn's disease. Infliximab should be always used at a dose of 5 mg/kg. The guidelines define the indications both in refractory and in fistulating disease for the readministration and before surgery. Guidelines for safety and for concomitant treatments are given. Prospects, potential clinical use, and future directions for the clinical development of other anti-TNF agents are detailed. Clinical use of anti-TNF agents will be influenced by a large number of clinical trials being concluded in 2001 and 2002. It is likely that anti-TNF therapies will become an important long-term therapy for a proportion of patients with Crohn's disease. Biological agents will be followed by smaller and more stable, orally available compounds. These guidelines will be succeeded by a formal public consensus in 2002/2003.

Crohn Disease↗
PubMed2001

Stochastic simulation of hemagglutinin-mediated fusion pore formation.

Studies on fusion between cell pairs have provided evidence that opening and subsequent dilation of a fusion pore are stochastic events. Therefore, adequate modeling of fusion pore formation requires a stochastic approach. Here we present stochastic simulations of hemagglutinin (HA)-mediated fusion pore formation between HA-expressing cells and erythrocytes based on numerical solutions of a master equation. The following elementary processes are taken into account: 1) lateral diffusion of HA-trimers and receptors, 2) aggregation of HA-trimers to immobilized clusters, 3) reversible formation of HA-receptor contacts, and 4) irreversible conversion of HA-receptor contacts into stable links between HA and the target membrane. The contact sites between fusing cells are modeled as superimposed square lattices. The model simulates well the statistical distribution of time delays measured for the various intermediates of fusion pore formation between cell-cell fusion complexes. In particular, these are the formation of small ion-permissive and subsequent lipid-permissive fusion pores detected experimentally (R. Blumenthal, D. P. Sarkar, S. Durell, D. E. Howard, and S. J., J. Cell Biol. 135:63-71). Moreover, by averaging the simulated individual stochastic time courses across a larger population of cell-cell-complexes the model also provides a reasonable description of kinetic measurements on lipid mixing in cell suspensions (T. Danieli, S. L. Pelletier, Y.I. Henis, and J. M. White, 1996, J. Cell Biol. 133:559-569).

Cell Fusion↗
PubMed2001

Activation of signal-transducer and activator of transcription 1 (STAT1) in pouchitis.

Activation of signal transducer and activator of transcription 1 (STAT1) is a hallmark of IFN-gamma receptor signal transduction but is also part of the signalling pathway of other cytokines/growth factor receptors. In ulcerative colitis, high levels of activation and expression of STAT1 have been observed in comparison with both Crohn's Disease and normal controls. Pouchitis develops in some patients after Ileal-Pouch-Anal-Anastomosis (IPAA). The pathophysiology and aetiology of pouchitis is still unclear. Recent studies have shown an increased production of proinflammatory cytokines including IFN-gamma. To investigate the expression and activation of STAT1 in pouchitis and the influence of treatment, patients were followed longitudinally from pouch operation. Diagnosis of pouchitis was made by clinical, endoscopic and histological criteria. Biopsies were obtained during routine endoscopy and snap frozen in liquid nitrogen. Nuclear and cytosolic extracts were prepared and the expression and activation of specific transcription factors were assessed by Western blot, electrophoretic mobility shift assay and immunofluorescence. Patients who develop pouchitis show highly increased levels of STAT1 alpha as well as STAT1 beta expression and activation in comparison with both normal pouch and normal ileal mucosa. Improvement of pouchitis during antibiotic therapy relates to a normalization of STAT1 expression and activation. We conclude that activation of STAT1 correlates to clinical disease activity and therefore STAT1 could play an important role in the pathophysiology of pouchitis. Similarities in the pattern of activation of STAT1 in pouchitis and ulcerative colitis may suggest a common pathway in the immunopathophysiology of both diseases.

Adult↗
PubMed2001

Absence of efficacy of subcutaneous antisense ICAM-1 treatment of chronic active Crohn's disease.

BACKGROUND & AIMS: ISIS-2302, an antisense oligonucleotide directed against intercellular adhesion molecule 1, was effective in steroid refractory Crohn's disease in a pilot trial. The aim of this study was to investigate safety and efficacy of ISIS-2302 in chronic active Crohn's disease (CACD). METHODS: A dose-interval, multicenter, placebo-controlled trial was conducted in 75 patients with steroid-refractory CACD (Crohn's Disease Activity Index [CDAI], 200-400). The primary endpoint was steroid-free remission (CDAI <150) at week 14. RESULTS: Only 2 of 60 (3.3%) ISIS-2302-treated and no placebo patients reached the primary endpoint. Steroid-free remission at week 26 (secondary endpoint) was reached in 8 of 60 (13.3%) active treatment and 1 of 15 (6.7%) placebo patients. A greater proportion of ISIS-2302-treated than placebo patients achieved a steroid dose <10 mg/day at weeks 14 and 26 (48.3% vs. 33.3% and 55.0% vs. 40.0%, respectively, and a glucocorticoid dose of 0 mg [prednisone equivalent] at week 26 [23.3% vs. 6.7%, respectively]). Treatment with ISIS-2302 was safe. The most common side effects were injection site reactions in the active treatment group (23% in ISIS-2302-treated patients vs. none in placebo patients). No statistically significant differences in the frequency of side effects were detected between dose groups. CONCLUSIONS: The trial did not prove clinical efficacy of ISIS-2302 based on the primary endpoint. Positive trends were observed in some of the secondary endpoints.

Adult↗
PubMed2001

Pituitary hormone mRNA in null cell adenomas and oncocytomas by in situ hybridization comparison with immunohistochemical and clinical data.

Null cell adenomas and oncocytomas are clinically inactive adenomas of the pituitary gland. They do not show any significant hormone content detectable by immunohistochemistry. This study aimed at demonstrating mRNAs for all main pituitary hormones in 32 null cell adenomas and 31 oncocytomas by non-isotopic in situ hybridization using digoxigenin-labeled oligonucleotide probes. The results were compared with immunohistochemical and clinical data. Immunohistochemistry (ABC method) was done with monoclonal antibodies against PRL, GH, FSH, LH, TSH, ACTH, alpha-subunit, and Ki-67 (mib-1). The signals for hormone production were detected in both adenoma types in a range from 42% for GH in oncocytomas to 78% for beta-FSH in null cell adenomas. However, these signals are apparently not effective on hormone production, as was shown by almost negative immunostaining. Owing to the simultaneous detection of at least two mRNAs in 78% of null cell adenomas and in 94% of oncocytomas, we assume that both tumor types originate from pluripotential precursor cells that are capable of producing various hormones. According to our data, it is unlikely that the signals influence the clinical behavior.

Adenoma↗
PubMed2001

An integrated system for high throughput TaqMan based SNP genotyping.

UNLABELLED: We have developed an integrated laboratory information system that allows the flexible handling of pedigree, phenotype and genotype information. Specifically, it includes client applications for an integrated data import from TaqMan typing files, Mendel checking, data export, handling of pedigree and phenotype information and analysis features. AVAILABILITY: The SQL source code, sources and binaries of the client applications (NT and Windows95/98 platforms) and additional documentation are available at http://www.mucosa.de/.

Clinical Laboratory Information Systems↗
PubMed2001

Coadministration of melatonin and fluoxetine does not improve the 3-month outcome following ECT.

At least 50% of patients with manic depressive disorder (MDD) treated successfully with electroconvulsive therapy (ECT) will experience a relapse within the first year of follow-up. Sleep disturbances are very common in MDD and may constitute forerunners of relapse. In this study we tested the hypothesis that melatonin, a sleep-promoting hormone, would decrease the 3-month relapse rate after successful ECT. We included in the study patients with MDD successfully treated with ECT (post-ECT Hamilton Rating Scale for Depression [HRSD] < or = 10). Patients were blindly randomized to two groups, one receiving fluoxetine + placebo and one receiving fluoxetine + melatonin. Assessments (HRSD, Brief Psychiatric Rating Scale, Global Assessment of Function Scale, Global Depression Scale, Pittsburgh Sleep Quality Index, Mini-Mental State Exam, and pill count) were performed for 12 weeks after ECT. Ten of the 35 patients (28.5%) relapsed during the follow-up period. Relapse rates were similar in both groups of patients. Sleep reports were not improved by melatonin. Patients who achieved a higher functional state post-ECT relapsed less often. We conclude that the addition of melatonin to on-going fluoxetine treatment did not have a beneficial effect either on the 3-month outcome post-ECT or on the sleep reports of these patients.

Aged↗
PubMed2001

Magnetic and seizure thresholds before and after six electroconvulsive treatments.

OBJECTIVES: Electroconvulsive therapy (ECT) is a well-established treatment in psychiatry. It has been reported that in patients with nondelusional major depression, transcranial magnetic stimulation (TMS) may substitute for ECT. To explore whether ECT and TMS share mechanisms of action, we studied the effects of ECT on both seizure threshold (ST) and magnetic motor threshold (MT). METHODS: We measured ST and MT in 10 patients referred for ECT. MT was defined as the minimal power of the TMS equipment at which a motor evoked potential (MEP) response could be detected 50% of the time. ST was defined as the minimal intensity of electrical stimulation needed to elicit an adequate seizure. ECT was performed following the methods recommended by the American Psychiatric Association. All subjects signed an informed consent for participation in the research. RESULTS: We measured MT and ST in 10 patients before and after 6 ECT treatments. No changes in MT were detected from the treatment (paired t-test: t = 1.05, SD = 4.78, p = 0.25). ST, on the other hand, increased significantly with treatment (paired t-test: t = 2.99, SD = 190.20, p < 0.001). CONCLUSIONS: ECT and TMS do not share a common mechanism at least with regard to MT and ST.

Adult↗
PubMed2001

Fine mapping of the chromosome 3p susceptibility locus in inflammatory bowel disease.

BACKGROUND AND AIMS: Genetic predisposition for inflammatory bowel disease (IBD) has been demonstrated by epidemiological and genetic linkage studies. Genetic linkage of IBD to chromosome 3 has been observed previously. A high density analysis of chromosome 3p was performed to confirm prior linkages and elucidate potential genetic associations. METHODS: Forty three microsatellite markers on chromosome 3 were genotyped in 353 affected sibling pairs of North European Caucasian extraction (average marker density 2 cM in the linkage interval). Marker order was defined by genetic and radiation hybrid techniques. RESULTS: The maximum single point logarithm of odds (LOD) score was observed for Crohn's disease at D3S3591. Peak multipoint LOD scores of 1.65 and 1.40 for the IBD phenotype were observed near D3S1304 (distal 3p) and near D3S1283 in the linkage region previously reported. Crohn's disease contributed predominantly to the linkage. The transmission disequilibrium test showed significant evidence of association (p=0.009) between allele 4 of D3S1076 and the IBD phenotype (51 transmitted v 28 non-transmitted). Two known polymorphisms in the CCR2 and CCR5 genes were analysed, neither of which showed significant association with IBD. Additional haplotype associations were observed in the vicinity of D3S1076. CONCLUSIONS: This study provides confirmatory linkage evidence for an IBD susceptibility locus on chromosome 3p and suggests that CCR2 and CCR5 are unlikely to be major susceptibility loci for IBD. The association findings in this region warrant further investigation.

Alleles↗
PubMed2001

Increased expression of IL-16 in inflammatory bowel disease.

BACKGROUND: Inflammatory bowel disease (IBD) is characterised by infiltration of inflamed mucosal regions with CD4(+) T lymphocytes and other mononuclear cells. Interleukin (IL)-16 exerts a strong chemoattractant activity on CD4(+) cells. Moreover, IL-16 activates expression and production of proinflammatory cytokines such as IL-1beta, IL-6, IL-15, and tumour necrosis factor alpha (TNF-alpha) in human monocytes. AIM: To examine if IL-16 expression is increased in IBD patients compared with healthy controls. METHODS: Twenty one patients with IBD (10 with ulcerative colitis (UC), 11 with Crohn's disease (CD)), seven disease specificity controls (DSC), and seven healthy controls were studied. Biopsies were taken during colonoscopies and IL-16 mRNA as well as protein expression were investigated by reverse transcriptase-polymerase chain reaction, ELISA, western blot, and immunohistochemistry. RESULTS: IL-16 mRNA and protein expression in the colonic mucosa of IBD patients were increased twofold compared with healthy controls, DSC, or IBD patients under steroid treatment. Most of the detected IL-16 protein was in its bioactive 17 kDa form and was predominantly expressed in eosinophils. Increased IL-16 expression in UC patients appeared to be mainly restricted to the inflamed regions of the colonic mucosa. Levels of caspase 3, which processes the 68 kDa IL-16 precursor molecule into the biological active 17 kDa form, were not increased. CONCLUSIONS: Our results provide evidence that IL-16 expression is significantly increased in the inflamed colonic mucosa of IBD patients but not in control individuals, DSC, or patients under steroid treatment. Therefore, upregulation of IL-16 expression seems to be specific for chronic intestinal inflammation and could lead to increased secretion of other proinflammatory cytokines in IBD.

Adult↗
PubMed2001

Low dose balsalazide (1.5 g twice daily) and mesalazine (0.5 g three times daily) maintained remission of ulcerative colitis but high dose balsalazide (3.0 g twice daily) was superior in preventing relapses.

BACKGROUND: Balsalazide is a new 5-aminosalicylic acid (5-ASA) containing prodrug. Its efficacy in comparison with standard mesalazine therapy and the optimum dose for maintaining remission of ulcerative colitis are still unclear. AIMS: To compare the relapse preventing effect and safety profile of two doses of balsalazide and a standard dose of Eudragit coated mesalazine. METHODS: A total of 133 patients with ulcerative colitis in remission were recruited to participate in a double blind, multicentre, randomised trial: 49 patients received balsalazide 1.5 g twice daily, 40 received balsalazide 3.0 g twice daily, and 44 received mesalazine 0.5 g three times daily. Efficacy assessments were clinical activity index (CAI) and endoscopic score according to Rachmilewitz, and a histological score. In addition, laboratory tests were performed and urinary excretion of 5-ASA and its metabolite N-Ac-5-ASA was analysed. The study lasted for 26 weeks. RESULTS: Balsalazide 3.0 g twice daily resulted in a significantly higher clinical remission rate (77.5%) than balsalazide 1.5 g twice daily (43.8%) and mesalazine 0.5 g three times daily (56.8%) (p=0.006). The respective times to relapse were 161 days, 131 days (p=0.003), and 144 days (NS). Accordingly, pairwise contrasts of the final endoscopic score demonstrated a significant difference (p=0.005) between the two balsalazide treatment groups while differences between either of these two groups and mesalazine were not statistically significant. Patients treated with balsalazide excreted less 5-ASA and N-Ac-5-ASA than patients receiving mesalazine but these differences were not statistically significant. Discontinuation of the trial because of adverse effects occurred in nine patients: three in the balsalazide 1.5 g twice daily group, two in the balsalazide 3.0 g twice daily group, and four in the mesalazine 0.5 g three times daily group. No clinically important new drug safety related findings were identified in this study. CONCLUSIONS: High dose balsalazide (3.0 g twice daily) was superior in maintaining remission in patients with ulcerative colitis compared with a low dose (1.5 g twice daily) or a standard dose of mesalazine (0.5 g three times daily). All three treatments were safe and well tolerated.

Aminosalicylic Acids↗
PubMed2001

Venous collateral blood flow assessed by Doppler ultrasound after unilateral radical neck dissection.

Removal of the internal jugular vein (IJV) in unilateral radical neck dissection (rND) necessitates redirection of cerebrovenous blood to collateral pathways. If adaptation is insufficient, neurologic sequelae develop that are due to impaired venous drainage and increased intracranial pressure. The authors studied venous hemodynamic effects of unilateral rND using Doppler and duplex ultrasound in 17 patients. Blood flow velocities (BFVs) were recorded from the distal IJV (dIJV) and the vertebral vein (VV) before and 9 to 88 days after surgery. A preoperative compression test of the dIJV was performed to identify the side of dominant drainage. The BFV increased in the contralateral dIJV after right-sided rND (n = 10) by 111% (range, 50% to 320%), and after left-sided rND (n = 7) by 34% (range, 5% to 105%). In the contralateral VV, a rise of BFV by 75% was found. Our results confirm the role of the contralateral dIJV as the predominant collateral pathway. The VVs serve as an important additional major outflow. Doppler ultrasound may help to identify patients at risk of insufficient cerebrovenous drainage after rND.

Blood Flow Velocity↗
PubMed2001

Cyclins D1 and D3 and topoisomerase II alpha in inactive pituitary adenomas.

The oncogenes cyclin D1 and D3 are overexpressed in many tumors. Topoisomerase II alpha is found in proliferating cells. The immunohistological expression of cyclin D1, cyclin D3, and Topoisomerase II alpha was studied in a collection of 60 clinically inactive surgically removed pituitary adenomas of the follicle-stimulating hormone/luteinizing hormone (FSH/LH) cell complex (20 null cell adenomas, 20 oncocytomas, and 20 FSH/LH cell adenomas) for correlation with other proliferation markers (Ki-67, PCNA) and with clinical data. Whereas cyclin D1 was positive only in one invasive null cell adenoma (1.7%) with some p53-positive nuclei, cyclin D3 was overexpressed in the nuclei of 41 tumors (68%). Topoisomerase II alpha was demonstrated in the nuclei of 42 adenomas (70%) with no significant differences discernible between the three adenoma subtypes. There was no significant correlation to the time of development of tumor symptoms, but a correlation of Topoisomerase II alpha with cyclin D3 and the proliferation marker Ki-67 (Mib1). From these data we conclude that cyclin D3 and Topoisomerase II alpha appear to be additional markers for proliferation which can be used for prognosis index in surgical pathology of the pituitary.

Adenoma↗
PubMed2001

GH-, PRL-, POMC-, beta-TSH-, beta-LH-, beta-FSH-mRNA in gonadotroph adenomas of the pituitary by in situ hybridization in comparison with immunostaining and clinical data.

In situ hybridization (ISH) enables the visualization of specific mRNA for pituitary hormones. Our collection consists of 40 surgically removed pituitary adenomas that were classified as follicle stimulating hormone/luteinizing hormone (FSH/LH) cell adenomas by structure and by immunostaining (IH) for all pituitary hormones. All forty adenomas were regarded as clinically inactive. The aim of our study was to examine nonfunctioning adenomas by ISH for demonstration of mRNAs for all pituitary hormones. The results were compared with proliferation markers, invasiveness and clinical data. ISH detected signals for all pituitary hormones at a range of 30% for prolactin (PRL) to 85% for proopiomelanocortin (POMC). mRNA for beta-FSH was detected in 70% and beta-LH mRNA in 43% of adenomas. Thirty-three percent of adenomas revealed negative mRNA detection for beta-LH but positive hormone content. The majority of adenomas (75%) expressed more than two mRNAs simultaneously, mostly the combination of POMC mRNA together with beta-FSH mRNA and one to four others. Comparison with clinical data showed no significant differences except for one adenoma with a high Ki-67 index (> 2.1% positive nuclei). This adenoma showed very high signals for PRL and beta-TSH mRNA.

Adenoma↗