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E Schmidt

Publications and source records attributed to E Schmidt.

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

Ensembl 2002: accommodating comparative genomics.

The Ensembl (http://www.ensembl.org/) database project provides a bioinformatics framework to organise biology around the sequences of large genomes. It is a comprehensive source of stable automatic annotation of human, mouse and other genome sequences, available as either an interactive web site or as flat files. Ensembl also integrates manually annotated gene structures from external sources where available. As well as being one of the leading sources of genome annotation, Ensembl is an open source software engineering project to develop a portable system able to handle very large genomes and associated requirements. These range from sequence analysis to data storage and visualisation and installations exist around the world in both companies and at academic sites. With both human and mouse genome sequences available and more vertebrate sequences to follow, many of the recent developments in Ensembl have focusing on developing automatic comparative genome analysis and visualisation.

Animals↗
PubMed2003

Gene structure of human carbamylphosphate synthetase 1 and novel mutations in patients with neonatal onset.

Carbamylphosphate synthetase 1 (E.C. 6.3.4.16) deficiency is a rare autosomal recessive disorder of the urea cycle that can result in severe neonatal hyperammonemia. Since the genomic structure of the CPS1 gene was not yet elucidated, mutation detection was performed by analysis of transcripts in the past. Here, we present the entire DNA sequence of the human CPS1 gene including all exon-intron boundaries. Moreover, mutation analysis was performed in six patients leading to the detection of 9 novel mutations including the missense mutations c.2528T>C and c.2623A>G, the nonsense mutations c.712C>T and c.2115ins35bp, the splice site mutations c.1263+5G>C, c.3558+1G>C and c.4101+2T>C, and a small deletion c.3036_3038delGGT. The mutations c.2528T>C and c.2623A>G were identified on a double mutated allele. New data on the genomic structure of the CPS1 gene provided in this study are useful to characterize the heterogenous molecular basis of the disease in patients deficient for carbamylphosphate 1 deficiency.

Age of Onset↗
PubMed2003

Continuous assessment of cerebral autoregulation: clinical and laboratory experience.

The method for the continuous assessment of cerebral autoregulation using slow waves of MCA blood flow velocity (FV) and cerebral perfusion pressure (CPP) or arterial pressure (ABP) has been introduced seven years ago. We intend to review its clinical applications in various scenarios. Moving correlation coefficient (3-6 min window), named Mx, is calculated between low-pass filtered (0.05 Hz) signals of FV and CPP or ABP (when ICP is not measured directly). Data from ventilated 243 head injuries and 15 patients after poor grade subarachnoid haemorrhage, 38 patients with Carotid Artery stenosis, 35 patients with hydrocephalus and fourteen healthy volunteers is presented. Good agreement between the leg-cuff test and Mx has been confirmed in healthy volunteers (r = 0.81). Mx also correlated significantly with the static rate of autoregulation and transient hyperaemic response test. Autoregulation was disturbed (p < 0.021) by vasospasm after SAH and worse in patients with hydrocephalus in whom CSF circulation was normal (p < 0.02). In head injury, Mx indicated disturbed autoregulation with low CPP (< 55 mmHg) and too high CPP (> 95 mmHg). Mx strongly discriminated between patients with favourable and unfavourable outcome (p < 0.00002). This method can be used in many clinical scenarios for continuous monitoring of cerebral autoregulation, predicting outcome and optimising treatment strategies.

Blood Flow Velocity↗
PubMed2003

[Diagnosis and follow-up in glaucoma patients using the Heidelberg retina tomograph].

The development of laser scanning tomography in the late 1980s enabled the possibility of an exact three-dimensional biomorphorphometry of the optic nerve head. This technique is designed for 3D measurement of the topography of the optic disc with high accuracy and reproducibility. With the development of the Heidelberg retina tomograph with highly advanced and user-friendly software, a quick examination is possible. Currently the instrument is already used on a routine basis in the ophthalmological practice. It has been shown that glaucomatous changes of the optic disc can be detected using laser scanning tomography before perimetric deterioration occurs. Therefore this technique is crucial in the follow-up of glaucoma patients.

Computer Graphics↗
PubMed2003

Diagnosis of N-acetylglutamate synthase deficiency by use of cultured fibroblasts and avoidance of nonsense-mediated mRNA decay.

Molecular diagnosis of N-acetylglutamate synthase deficiency (NAGSD) has become possible now that the corresponding gene has been identified. We describe the genetic analysis of a patient with NAGSD using low-level transcripts derived from cultured fibroblasts. One defective allele (c.1306-1307insT) was detected by PCR amplification. However, the transcript from a second mutation (IVS3 - 2A>T), causing aberrant splicing with the generation of a premature termination codon, was not detected until interference of nonsense-mediated mRNA decay was abrogated by the translation inhibitor cycloheximide. We demonstrate that low-level transcripts in cells that do not express significant enzyme activity are a valuable tool for molecular studies of genetic alterations, and suggest routine abrogation of nonsense-mediated mRNA decay using cycloheximide when transcript analysis is performed.

Acetyltransferases↗
PubMed2003

Protein A immunoadsorption: a novel and effective adjuvant treatment of severe pemphigus.

BACKGROUND: Pemphigus foliaceus (PF) and pemphigus vulgaris (PV) are autoimmune blistering skin diseases usually treated with high-dose systemic corticosteroids and other immunosuppressants that may cause severe side-effects. Plasmapheresis also has been demonstrated to be of benefit in the treatment of pemphigus. In contrast to plasmapheresis, staphylococcal protein A immunoadsorption (PA-IA) specifically removes immunoglobulin from the circulation, allows treatment of larger plasma volumes, and does not require the substitution of plasma components. OBJECTIVES: To determine the effectiveness and side-effects of PA-IA in patients with severe pemphigus. METHODS: Five patients with severe pemphigus (PV, n = 4; PF, n = 1) were treated by PA-IA. Three of these patients had been refractory to various treatment regimens. In addition to PA-IA, methylprednisolone, 0.5 mg x kg-1 body weight day-1 was given initially and subsequently tapered. RESULTS: In all patients, a dramatic clinical improvement was seen within 2 weeks after initiation of therapy. Patients were free of lesions after 3, 4, 4, 10 and 21 weeks of treatment, respectively. Concurrently, autoantibody levels decreased rapidly. CONCLUSIONS: PA-IA is a rational, effective, and safe adjuvant therapy for severe pemphigus and warrants wider use for this indication. A controlled study should compare side-effects and effectiveness of PA-IA with other treatment options for pemphigus.

Adjuvants, Immunologic↗
PubMed2002

The Ensembl genome database project.

The Ensembl (http://www.ensembl.org/) database project provides a bioinformatics framework to organise biology around the sequences of large genomes. It is a comprehensive source of stable automatic annotation of the human genome sequence, with confirmed gene predictions that have been integrated with external data sources, and is available as either an interactive web site or as flat files. It is also an open source software engineering project to develop a portable system able to handle very large genomes and associated requirements from sequence analysis to data storage and visualisation. The Ensembl site is one of the leading sources of human genome sequence annotation and provided much of the analysis for publication by the international human genome project of the draft genome. The Ensembl system is being installed around the world in both companies and academic sites on machines ranging from supercomputers to laptops.

Computational Biology↗
PubMed2002

Interaction of fibronectin and aggregation substance promotes adherence of Enterococcus faecalis to human colon.

This in vitro study investigates the interaction between aggregation substance (AS), a virulence factor of Enterococcus faecalis, and colonic mucosal fibronectin in normal colon and colon from patients with Crohn's disease. Fibronectin was found to be overexpressed in Crohn's disease compared to normal colon. Compared to E. faecalis OG1X:pAM944 (AS-negative), E. faecalis OG1X:pAM721 (expressing AS) showed a significantly enhanced adhesion to human colonic mucosa in normal colon and in colon from patients with Crohn's disease. Double-staining of fibronectin and AS-positive enterococci showed that colocalization of bacteria and fibronectin was significantly more frequent in Crohn's disease than in normal colon. Preincubation of bacteria with soluble fibronectin caused a significant reduction in the adherence to fibronectin. In conclusion, the interaction between AS and fibronectin plays is an important factor that mediates adhesion of Enterococcus faecalis to colonic mucosa. This might be one of the mechanisms responsible for bacterial translocation of Enterococcus faecalis.

Bacterial Adhesion↗
PubMed2002

Childhood epidermolysis bullosa acquisita: a novel variant with reactivity to all three structural domains of type VII collagen.

Most patients with epidermolysis bullosa acquisita develop an autoimmune response to the non-collagenous (NC) 1 domain of type VII collagen. We report a 4-year-old girl of white European descent presenting with widespread blistering disease involving the face, hands, genital area and oral mucosa. Histopathology revealed subepidermal blisters, and linear deposits of IgG and C3 were seen along the dermal-epidermal junction on direct immunofluorescence (IF) microscopy of a perilesional skin biopsy. On indirect IF microscopy, circulating autoantibodies exclusively stained the dermal side of 1 mol L-1 NaCl-split skin. The patient's IgG autoantibodies labelled a 290-kDa protein on Western blotting of dermal extracts, and reacted with the NC1, NC2 and triple helical domains of type VII collagen on immunoblotting of recombinant and cell-derived fragments obtained by pepsin and collagenase digestion of the full-length protein. Oral methylprednisolone and dapsone led to clearance of lesions, which healed with mild scarring and milia formation. Treatment was discontinued after 1 year and the patient has now been in remission for more than 3 years.

Autoantibodies↗
PubMed2002

[Transillumination technique in difficult intubations in heart surgery].

OBJECTIVE: The avoidance of myocardial depression still remains the goal of the management for cardiosurgical patients, also when unexpected difficulties in intubation face the anaesthetist. Therefore the difficult intubation should be managed by a short and easy procedure which provides safe results. To analyse the use of transillumination technique with a lightwand device (Trachlight(R), Laerdale, USA) in case of unexpected difficult intubation is the aim of our report. Methods All cardiosurgical patients (NYHA II - IV) were included from Jan 1998 - Dec 2001. After failure of the first intubation attempt by means of direct laryngoscopy (with non-adjustable vocal cord level) this intubation was qualified as an difficult intubation. In all these cases a lightwand device (Trachlight(R), Laerdale, USA) was applicated. Success, duration of the procedure, blood pressure, heart rate were recorded. Results 195 patients (out of total 7406) who could not be directly intubated by laryngoscopy (vocal cord level and arytenoid cartilage not visible), were classified as a difficult intubation. During the first year 1998 the light guided intubation (LGI) was successful as secondary procedure in 94 %, 3 cases, in which LGI failed the intubation was performed by fiberoptic method or McCoy blade. From 1999 to 2001 all difficult intubation could be managed by light guided intubation. In all cases of unexpected difficult intubation the procedure of the light guided intubation took as less than 3 min. The directly measured arterial blood pressure elevated by 14 % in comparison with the pressure prior to the passage through the larynx. Discussion and Conclusions 1998 after sufficient familiarisation of staff with the light wand device the transillumination technique was introduced as an alternative of using the McCoy blade or of using the fiberoptic method in the case of difficult intubation. Short neck or obesity, which occur as main reasons for intubation problems are surprisingly easy to control by light wand device. Therefore the light guided intubation could be an alternative procedure for unexpected difficult intubation in the setting of adult cardiac anesthesia.

Aged↗
PubMed2002

Occurrence of osteopenia among adolescent girls with oligo/amenorrhea.

The occurrence of reduced bone mineral density (BMD) among adolescent girls with oligomenorrhea or secondary amenorrhea, due to 'pure' dysfunction of the hypothalamo-pituitary-ovarian (HPO) axis (without anorexia nervosa, excessive sport or ballet, slimming diet, etc.) was examined. The study group consisted of 19 adolescent girls (age 16-18 years) with oligo/amenorrhea. Clinical (height, weight, age at menarche, duration of amenorrhea, body mass index (BMI)), hormonal (follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol, progesterone, testosterone, prolactin), and ion (calcium, sodium, potassium, phosphate, chloride) parameters and the BMD of the lumbar spine were investigated. Correlations between BMD and other parameters were also examined. Twenty healthy volunteers (same age and regular cycles) served as controls. Three girls had osteoporosis, with a BMD below -2 standard deviations (SD). Ten showed osteopenia, with a BMD value between -1 and -2 SD. Only six of the study group had a normal BMD within +/- 1 SD. A positive correlation was observed between the BMD and the BMI (r = 0.73; p < 0.05). All the controls had normal hormonal, ion and BMD parameters. 'Pure' dysfunction of the HPO axis in adolescents, causing oligomenorrhea or secondary amenorrhea, might result in reduced BMD and, consequently, lower peak bone mass. Treatment of menstrual cycle disorders is necessary for the prevention of osteoporosis.

Adult↗
PubMed2001

Environmental exposure to polychlorinated biphenyls and quality of the home environment: effects on psychodevelopment in early childhood.

BACKGROUND: There is uncertainty whether environmental levels of exposure to polychlorinated biphenyls (PCBs) adversely affect mental and motor development in early childhood. We aimed to establish whether such an effect is of only prenatal or additional postnatal origin, and if a favourable home environment can counteract this effect. METHODS: Between 1993 and 1995 we recruited 171 healthy mother-infant pairs and prospectively measured psychodevelopment in newborn infants aged 7, 18, 30, and 42 months. We estimated prenatal and perinatal PCB exposure of newborn babies in cord blood and maternal milk. At 42 months we measured postnatal PCB concentrations in serum. At 18 months the quality of the home environment was assessed using the Home Observation for Measurement of the Environment scale. Mental and psychomotor development of the children were assessed using the Bayley Scales of Infant Development until 30 months and the Kaufman Assessment Battery for Children at 42 months. FINDINGS: Negative associations between milk PCB and mental/motor development were reported at all ages, becoming significant from 30 months onwards. Over 30 months, for a PCB increase from 173 (5th percentile) to 679 ng/g lipids in milk (95th percentile) there was a decrease of 8.3 points (95% CI -16.5 to 0.0) in the Bayley Scales of Infant Development mental scores, and a 9.1 point decrease (95% CI -17.2 to -1.02) in the Bayley Scales of Infant Development motor scores. There was also a negative effect of postnatal PCB exposure via breastfeeding at 42 months. Home environment had a positive effect from 30 months onwards (Bayley Scales of Infant Development mental score increase of 9.4 points [95% CI 2.2-16.7]). INTERPRETATION: Prenatal PCB exposure at current European background levels inhibits, and a favourable home environment supports, mental and motor development until 42 months of age. PCB exposure also has an effect postnatally.

Air Pollution, Indoor↗
PubMed2001

Histone deacetylase inhibitors arrest polyglutamine-dependent neurodegeneration in Drosophila.

Proteins with expanded polyglutamine repeats cause Huntington's disease and other neurodegenerative diseases. Transcriptional dysregulation and loss of function of transcriptional co-activator proteins have been implicated in the pathogenesis of these diseases. Huntington's disease is caused by expansion of a repeated sequence of the amino acid glutamine in the abnormal protein huntingtin (Htt). Here we show that the polyglutamine-containing domain of Htt, Htt exon 1 protein (Httex1p), directly binds the acetyltransferase domains of two distinct proteins: CREB-binding protein (CBP) and p300/CBP-associated factor (P/CAF). In cell-free assays, Httex1p also inhibits the acetyltransferase activity of at least three enzymes: p300, P/CAF and CBP. Expression of Httex1p in cultured cells reduces the level of the acetylated histones H3 and H4, and this reduction can be reversed by administering inhibitors of histone deacetylase (HDAC). In vivo, HDAC inhibitors arrest ongoing progressive neuronal degeneration induced by polyglutamine repeat expansion, and they reduce lethality in two Drosophila models of polyglutamine disease. These findings raise the possibility that therapy with HDAC inhibitors may slow or prevent the progressive neurodegeneration seen in Huntington's disease and other polyglutamine-repeat diseases, even after the onset of symptoms.

Acetylation↗
PubMed2001

CD19+ B lymphocytes are the major source of human antibody-secreting hybridomas generated by electrofusion.

Human monoclonal antibodies may be generated by electrofusion of human B lymphocytes with a human/mouse heteromyeloma line. In addition to a fusion protocol optimised for the fusion partners, the activation of B lymphocytes is crucial for fusion and hybrid efficiency. In this study, we initially treated peripheral blood mononuclear cells (PBMC) from normal blood donors with a large panel of known stimulants and determined the yield of human antibody-secreting hybridomas after electrofusion with the heteromyeloma cell line H73C11; 3- to 5-day incubation with phytohaemagglutinin L (PHA-L) resulted in the highest number of secreting hybrids. In a second set of experiments, PBMC were depleted from various cell populations, including CD14+ monocytes, CD8+ T lymphocytes, and CD2+ T cells, respectively. Undepleted PBMC stimulated with PHA-L were shown to give rise to the highest number of secreting hybridomas when subjected to electrofusion, whereas depletion of CD2+ T lymphocytes greatly reduced the yield. In a final set of experiments, CD19+ B lymphocytes were identified as the major source of secreting hybridomas. For optimal fusion efficiency, CD19+ B cells were shown to require direct physical contact with other cell populations, most probably T lymphocytes, during the stimulation process. Our data highlight the importance of an adequate stimulation prior to electrofusion and may be helpful to further facilitate the development of human monoclonal antibodies.

Animals↗
PubMed2001

Antibodies to desmogleins 1 and 3, but not to BP180, induce blisters in human skin grafted onto SCID mice.

Pemphigus and bullous pemphigoid (BP) are blistering skin diseases associated with IgG autoantibodies to desmosomal and hemidesmosomal components. When autoantibodies to desmogleins 1 and 3 from patients with pemphigus foliaceus (PF) and pemphigus vulgaris (PV) or rabbit antibodies against the murine hemidesmosomal component BP180 are passively transferred into neonatal mice, they induce blisters in the skin of the mice. To develop an animal model that would duplicate the findings in the skin of the patients more closely, full-thickness human skin from healthy volunteers was grafted onto SCID mice. Injection of the purified IgG fraction from the serum of PF and PV patients led to subcorneal and suprabasal splits in the human grafts and human IgG was deposited intercellularly in the upper and lower layers of the epidermis, respectively. Interestingly, anti-BP180 autoantibodies purified from the serum of BP patients and from a rabbit immunized with recombinant human BP180 strongly bound to the basement membrane zone of the grafts (n=32), fixed murine complement, led to the recruitment of neutrophils to the upper dermis of the graft, but did not induce subepidermal blisters. We report a novel experimental model for PF and PV which should greatly facilitate further studies to dissect the immunopathological mechanisms in these diseases. Specifically, this model can be used to identify pathogenically relevant epitopes on human desmogleins 1 and 3 and to develop novel strategies for the treatment of pemphigus.

Animals↗