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J Lohmann

Publications and source records attributed to J Lohmann.

At least 19 recordsLinked to original sources
PubMed2004

Lack of genetic association of the three more common polymorphisms of CARD15 with psoriatic arthritis and psoriasis in a German cohort.

OBJECTIVE: To determine whether the three common independent sequence variants of the putative pleiotropic non-MHC autoimmune gene CARD15 influence disease susceptibility in large German cohorts of patients with psoriatic arthritis and psoriasis vulgaris, before and after stratification to HLA-C. METHODS: DNA was obtained from 375 patients with psoriatic arthritis, 281 patients with psoriasis vulgaris without joint involvement, and 376 controls. The three variants of the CARD15 gene (R702W, G908R, leu1007fsinsC), and two single nucleotide polymorphisms of the HCR gene (HCR-325, HCR-2327) for HLA-C stratification were genotyped using allelic discrimination Taqman assays. RESULTS: No significant differences in genotype frequencies were observed between controls and either the psoriatic arthritis or the psoriasis vulgaris patient population, even after stratification to HLA-C in both patient cohorts, or to the type of joint involvement within the psoriatic arthritis group. CONCLUSIONS: The lack of genetic association between the most common Crohn's disease alleles of the CARD15 gene and psoriatic joint disease on large cohorts of white patients does not support a recently claimed role for CARD15 as the first non-MHC susceptibility gene in the pathogenesis of psoriatic arthritis, but confirms and extends previous studies in the case of psoriasis vulgaris.

Adolescent↗
PubMed2001

Glucagon-like peptide 2 improves nutrient absorption and nutritional status in short-bowel patients with no colon.

BACKGROUND & AIMS: Glucagon-like peptide 2 (GLP-2) is intestinotrophic, antisecretory, and transit-modulating in rodents, and it is mainly secreted from the intestinal mucosa of the terminal ileum and colon after food ingestion. We assessed the effect of GLP-2 on the gastrointestinal function in patients without a terminal ileum and colon who have functional short-bowel syndrome with severe malabsorption of wet weight (>1.5 kg/day) and energy (>2.3 MJ/day) and no postprandial secretion of GLP-2. METHODS: Balance studies were performed before and after treatment with GLP-2, 400 microg subcutaneously twice a day for 35 days, in 8 patients (4-17 years from last bowel resection; 6 with Crohn's disease). Four patients received home parenteral nutrition (mean residual jejunum, 83 cm), and 4 did not (mean ileum resection, 106 cm). Biopsy specimens were taken from jejunal/ileal stomas, transit was measured by scintigraphy, and body composition was measured by dual-energy x-ray absorptiometry. RESULTS: Treatment with GLP-2 improved the intestinal absorption of energy 3.5% +/- 4.0% (mean +/- SD) from 49.9% to 53.4% (P = 0.04), wet weight 11% +/- 12% from 25% to 36% (P = 0.04), and nitrogen 4.7% +/- 5.4% from 47.4% to 52.1% (P = 0.04). Body weight increased 1.2 +/- 1.0 kg (P = 0.01), lean body mass increased 2.9 +/- 1.9 kg (P = 0.004), fat mass decreased 1.8 +/- 1.3 kg (P = 0.007), and 24-hour urine creatinine excretion increased (P = 0.02). The time to 50% gastric emptying of solids increased 30 +/- 16 minutes from 89 to 119 minutes (P < 0.05). Small bowel transit time was not changed. Crypt depth and villus height were increased in 5 and 6 patients, respectively. CONCLUSIONS: Treatment with GLP-2 improves intestinal absorption and nutritional status in short-bowel patients with impaired postprandial GLP-2 secretion in whom the terminal ileum and the colon have been resected.

Adult↗
PubMed1999

A head-activator binding protein is present in hydra in a soluble and a membrane-anchored form.

The neuropeptide head activator plays an important role for proliferation and determination of stem cells in hydra. By affinity chromatography a 200 kDa head-activator binding protein, HAB, was isolated from the multiheaded mutant of Chlorohydra viridissima. Partial amino acid sequences were used to clone the HAB cDNA which coded for a receptor with a unique alignment of extracellular modules, a transmembrane domain, and a short carboxy-terminal cytoplasmic tail. A mammalian HAB homologue with identical alignment of these modules is expressed early in brain development. Specific antibodies revealed the presence of HAB in hydra as a transmembrane receptor, but also as secreted protein, both capable of binding head activator. Secretion of HAB during regeneration and expression in regions of high determination potential hint at a role for HAB in regulating the concentration and range of action of head activator.

Amino Acid Sequence↗
PubMed1998

Time-dependent changes in the density and hemoglobin F content of biotin-labeled sickle cells.

Sickle red blood cells (RBC) are subject to a number of important cellular changes and selection pressures. In this study, we validated a biotin RBC label by comparison to the standard 51Cr label, and used it to study changes that occur in sickle cells as they age. Sickle RBC had a much shorter lifespan than normal RBC, but the two labels gave equivalent results for each cell type. A variable number of sickle, but not normal, RBC disappeared from the circulation during the first few hours after reinfusion. The number of biotinylated sickle reticulocytes was decreased by 50% after 24 h and 75% after 48 h, with a gradual decrease in the amount of reticulum per cell. The labeled sickle cells exhibited major density increases during the first 4-6 d after reinfusion, with smaller changes thereafter. A small population of very light, labeled sickle RBC was essentially constant in number after the first few days. Fetal hemoglobin (HbF) content was determined in isolated biotinylated sickle RBC after reinfusion, allowing an estimate of lifespan for RBC containing HbF (F cells) and non-F cells. The lifespan of sickle biotinylated RBC lacking HbF was estimated to be approximately 2 wk, whereas F cells survived 6-8 wk.

Anemia, Sickle Cell↗
PubMed1997

Systematic isolation of peptide signal molecules regulating development in hydra: LWamide and PW families.

To isolate new peptide signal molecules involved in regulating developmental processes in hydra, a novel screening project was developed. Peptides extracted from the tissue of Hydra magnipapillata were systematically purified to homogeneity using HPLC. A fraction of each purified peptide was examined by differential display-PCR for its ability to affect gene expression in hydra. Another fraction was used to determine the tentative structure using an amino acid sequence analyzer and/or a mass spectrometer. Based on the results, peptides of potential interest were selected for chemical synthesis, followed by confirmation of the identity of the synthetic with the native peptides using HPLC. Using this approach, 286 peptides have been isolated, tentative amino acid sequences have been determined for 95 of them, and 19 synthetic peptides identical to native ones were produced. The 19 synthetic peptides were active in a variety of biological tests. For example, Hym-54 stimulated muscle contraction in adult polyps of hydra and sea anemone, Anthopleura fuscoviridis, and induced metamorphosis of planula, the larval stage, into polyps in a marine hydrozoan species, Hydractinia serrata. Another peptide, Hym-33H, inhibited nerve cell differentiation in hydra and induced tissue contraction in planula of Hydractinia serrata. The evidence obtained so far suggests that hydra contains a large number (>350) of peptide signal molecules involved in regulating developmental or other processes in cnidaria. These peptides can be isolated and their functions examined systematically with the new approach developed in this study.

Amino Acid Sequence↗
PubMed1993

[Liver cirrhosis and chronic hepatic porphyria].

Chronic hepatic porphyrias (CHP) are associated with different degrees of liver damage. They range from minimal histological changes to cirrhosis and primary liver carcinomas. Forty patients with early stages of porphyrias were compared to 85 patients with clinically manifest porphyrias, Porphyria cutanea tarda. This comparison resulted in the fact that cirrhosis occurred more often in early (or latent) stages (65%) than in PCT (31%) confirmed by laparoscopy. Thus the severity of the liver disease does not depend on the duration and intensity of cutaneous symptoms or pathobiochemical syndromes but they more often depend on the long-term influence of so-called trigger factors, among them above all alcohol and iron overloading. We conclude that the proof of latent CHP has an index function for severer liver damage.

Female↗
PubMed1987

Concentration of fibronectin and granulocyte elastase in plasma of patients with systemic connective-tissue diseases.

The concentration of granulocyte elastase-alpha-1-protease inhibitor (E-AT) complex in plasma is enhanced in inflammatory processes, e.g. in septicaemia and rheumatoid arthritis, being an expression of granulocyte activation during inflammatory response. In the present study we measured E-AT and fibronectin in the plasma of 46 patients with various connective-tissue diseases in relation to the course of the disease. In about 50% of the cases, E-AT was found to be elevated to 2-3 times the normal concentrations, in relation to increasing serum content of C-reactive protein. In follow-ups over 2 years, an elevation of E-AT and a decreasing fibronectin in plasma was found in patients with activated disease. Without relation to other parameters used in connective-tissue diseases, fibronectin was found to be diminished below the normal range in 7 patients with systemic lupus erythematodes and 1 patient with overlapping syndrome. Our results indicate that the concentration of E-AT and fibronectin in plasma may be helpful parameters for judging the activity of connective-tissue diseases.

Adolescent↗
PubMed1985

[Liver lesions induced by dihydralazine and propranolol].

The antihypertensive drugs dihydralazine and propranolol can produce identical liver injuries which must be distinguished clinically and morphologically from acute viral hepatitis. In 19 cases selected from our biopsy file during the last two years, clinical and morphological findings suggested that the liver injury diagnosed by light microscopy had been caused by an adverse reaction to dihydralazine and/or propranolol. In order to establish a causal relation the lymphocyte proliferation test (LPT) was performed with dihydralazine in 11 cases. Positive results were observed in 9 cases, demonstrating an etiologic role for dihydralazine in liver injury in these cases. The dihydralazine and/or propranolol induced liver injury consisted mainly of drug-induced hepatitis with confluent (bridging) necrosis. Different findings were observed in three cases: In two of these drug-induced hepatitis with confluent necrosis was observed together with eosinophilic cholangio-cholangiolitis. In one other case the histologic changes corresponded to drug hepatitis resembling viral hepatitis. Each of the three cases showed conspicuous centrolobular cholestasis, a feature which is unusual in drug-induced hepatitis with confluent necrosis irrespective of serum bilirubin levels. In one third of our cases we found morphological features of hypersensitivity reactions in the liver biopsies. Considered together with the results of LPT these features emphasize the role of cell mediated immune reaction in the mechanism of liver injury caused by dihydralazine and/or propranolol.

Biopsy↗
PubMed1984

The influence of paracetamol on the hepatic biosynthesis of lecithin.

In paracetamol induced liver injury changes in the phospholipid components of microsomal membranes are usual. Direct incubation of paracetamol with subcellular fractions of human liver specimens did not alter the biosynthesis of lecithin. Preincubation of liver slices with paracetamol led to an increased synthesis of lecithin. The presence of intact cells and the integrity of hepatocellular function seem to be a prerequisite for the poisoning effects in vitro.

Acetaminophen↗
PubMed1984

The rare occurrence of a radiation-induced osteosarcoma in the clavicule after treatment of thyroid cancer.

The authors report on a postirradiation osteosarcoma of the clavicule in a patient treated for thyroid cancer. The total absorbed dose to the right clavicule was estimated 149 Gy (60 Co and 18 MeV elektron beam). The findings are demonstrated on plain radiographs, CT-scan and bone scintigraphy. The literature on this subject is reviewed and the possible pathogenesis discussed.

Adenoma↗