Search PubMed⌕ Search

Biomedical subjects

H Bartels

Publications and source records attributed to H Bartels.

At least 199 records · Page 11Linked to original sources
PubMed1981

Further delineation of the C (trigonocephaly) syndrome.

This communication brings the number of recognized cases of the C (trigonocephaly) syndrome to 11. The pattern of findings includes an anomaly of the anterior cranium and frontal cortex (trigonocephaly), the root of the nose (broad nasal bridge, epicanthus, and short nose), and palate (thick anterior alveolar ridges); abnormalities of the limbs (polysyndactyly, bridged palmar creases, short limbs, and joint dislocations and/or contractures); visceral defects (congenital heart defects, cryptorchidism, and abnormal lobulations of the lungs and kidneys). Auricular, mandibular, skin, and genital abnormalities also occur. Consistent neurological findings are hypotonia, strabismus, and psychomotor retardation; seizures have been reported. Normal chromosomes, normal parents with multiple affected offspring, equal sex ratio of affected individuals, and consanguineous matings all support autosomal recessive inheritance of the C syndrome. In autopsied cases, there has been a suggestion of defective central nervous system myelination. About 1/2 of the case have died within the first year. All survivors have severe to profound mental retardation except for one child who has moderate retardation.

Abnormalities, Multiple↗
PubMed1981

Germinal center cell lymphomas: prognostic significance of their histopathological differentiation.

Clinical data of 48 patients with centrocytic, 83 patients with centroblastic/centrocytic and 64 patients with centroblastic lymphoma who had entered a prospective multicenter study of the Kiel Lymphoma Study Group since October 1975 were compared. Advanced (stage IV) disease at time of diagnosis, predominantly due to bone marrow infiltration, was most frequent in centrocytic (69% of patients) and in centroblastic/centrocytic (51% of patients) lymphomas as compared to only 28% of patients with centroblastic lymphoma. High survival probability of patients with localized centrocytic and centroblastic/centrocytic lymphomas after radiotherapy, contrasting with a worse prognosis of corresponding patients with centroblastic lymphoma, is compatible with the classification of these lymphoma entities as neoplasias of low-grade malignancy. However, as shown by this prospective and previous retrospective trials overall survival probability of patients with advanced centrocytic lymphoma was inferior to that observed in corresponding patients with centroblastic/centrocytic lymphoma. These findings suggest the possibility that patients with advanced centrocytic lymphoma occupy an intermediate position between typical low-grade and typical high-grade malignant non-Hodgkin lymphomas.

Adult↗
PubMed1981

Clinical and prognostic heterogeneity of non-Hodgkin lymphomas of high-grade malignancy.

Comparison of clinical data of 64 patients with centroblastic lymphoma, 55 patients with immunoblastic lymphoma and 31 patients with lymphoblastic lymphoma not only confirmed the original assumption of high-grade malignancy as proposed by the concept of the Kiel classification but also demonstrated distinct clinical differences, particularly between lymphoblastic lymphoma and the two other entities. Rapid lymph node enlargement as well as steep fall of survival curves within the first year after diagnosis were common characteristics. Bimodal age distribution, predominance of males and early generalization of disease were typical features of lymphoblastic lymphoma; elderly patients and patients with the unclassified subtypes of lymphoblastic lymphoma exhibited the worst prognosis. Whereas patients with centroblastic and immunoblastic lymphomas showed similar distribution of age, sex and initial stage of disease, patients with immunoblastic lymphoma presented more frequently with a reduced performance status and showed a poorer response to radio- and chemotherapy resulting in a worse prognosis discernible after the first year of follow-up. Generalization during course of the disease was significantly more frequent in immunoblastic than in centroblastic lymphoma.

Adolescent↗
PubMed1981

Blood oxygen transport and organ weights of small bats and small non-flying mammals.

Blood oxygen transport properties and organ weights of five bat species in the weight range between 4.8 and 150 g have been investigated and compared to four similar-size non-flying mammals. In addition allometric organ weight-body weight relations have been compiled for both groups. All bats had higher relative heart weights than the terrestrial mammals. In both groups the relative heart weight increased with decreasing body weight. In bats hemoglobin concentrations (18.2--24.4 g Hb/dl), hematocrits (51--63%), and red blood cell counts (11.0 x 10(6)--26.2 x 10(6) RBC/microliter) were remarkably increased compared to non-flying mammals (15.3--17.4 g Hb/dl, 44--50% Hct, 8.8 x 10(6)--18.3 x 10(6) RBC/microliters). The highest values have been found in the smallest european bat Pipistrellus pipistrellus (4.8 g), they exceeded by far the results of the smallest terrestrial mammal, the shrew Suncus etruscus (2.5 g). Oxygen half saturation pressures and Bohr factors did not show considerable differences between similar-size flying and non-flying mammals. Our results indicate that the higher specific oxygen uptake of flying bats compared to exercising non-flying mammals is mainly enabled by larger hearts and larger blood oxygen capacities.

Animals↗
PubMed1980

Parathyroid function and serum calcitonin in children receiving anticonvulsant drugs.

Serum calcitonin (CT) levels and other aspects of calcium metabolism were investigated in 40 epileptic children receiving long-term treatment with phenytoin and/or other anticonvulsant drugs, and in 38 age-matched controls. In the patients CT levels were significantly lower. Immunoreactive parathyroid hormone (iPTH) was significantly elevated exceeding the upper limit of controls in 11 patients. We also observed a highly significant correlation between iPTH and urinary cyclic AMP (cAMP) excretion but a lack of such a correlation with the renal handling of phosphate; this indicates to us a dissociation between cAMP production and phosphaturia. A significant correlation between iPTH levels and urinary hydroxyproline excretion points to a normal action of PTH on bone in the patients. The low CT levels are not due to hypocalcemia and may be directly attributed to the effects of anticonvulsant drugs. As the primary effect of CT is a direct inhibition of PTH induced calcium loss from bone, the drug-related low CT levels in association with secondary hyperparathyroidism possibly is an additional factor in anticonvulsant bone disease.

Adolescent↗
PubMed1980

[Reinterventions following the implantation of atrial electrodes (author's transl)].

During the past 3 years 41 atrial electrodes (36 J-leads and 5 screw-in electrodes) were implanted for stimulation and/or triggering in 39 patients selected by haemodynamic criteria. In seven patients (18%) reinterventions had to be performed because of a rise in threshold (four cases) and dislocation or unstable position of the electrode (three cases). Reposition of the electrode was successful in only one case, while in four cases a ventricular electrode was implanted and the stimulation mode converted to ventricular pacing. In two other patients the complication was managed by changing the type of electrode.

Cardiac Pacing, Artificial↗
PubMed1980

A simple test for urinary lactic acid.

A new simple rapid test for the detection of increased urinary lactic is described. The method depends on the transformation of lactic acid to acetaldehyde by cesium IV. Acetaldehyde reacts with sodium nitroprusside prducing a blue color. Patients from an emergency ward and patients with experimentally induced hyperlactatemia have been screened with this test. The results confirm that there exists a correlation between blood and urinary lactate levels and that a clinically relevant hyperlactemia is associated with an increased urinary lactate concentration which can be reliably detected with this test.

Acidosis↗
PubMed1980

Communicating-occluding junction complexes in the alveolar epithelium. A freeze-fracture study.

Because studies differ as to the presence of communicating (gap) junctions in the alveolar epithelium, lung tissue from several mammalian species (man, dog, rabbit, rat, and mouse) was studied with the freeze-fracture method to clarify this problem. Communicating junctions were found between pneumonocytes in each species examined. They were always located within the meshes of or closely attached to the occluding junctions, forming communicating-occluding junction complexes. It is assumed that the communicating junctions between pneumonocytes serve mainly for metabolic coupling. The particular location of communicating junctions within the meshes of the occluding junction may be related to an additional mechanical function.

Animals↗
PubMed1980

[Effect of damaged liver parenchyma, renal insufficiency and hemodialysis on the pharmacokinetics of cyclophosphamide and its activated metabolites].

Patients with impaired liver function have a reduced biotransformation rate of the cytostatic agent cyclophosphamide. With pathologically reduced serum cholinesterase activity the half-life of the drug increases from normally 4.3 h to 6.7 h. These patients show significantly lower peak levels of activated cyclophosphamide (4-hydroxy-cyclophosphamide + aldophosphamide). Because of the low renal clearance of cyclophosphamide (16 ml/min) and equally low renal excretion of activated cyclophosphamide amounting to only 1% of the applied dose more than 80% of the drug is still metabolized and the area under the curve of activated cyclophosphamide (cXt) remains relatively constant. No change in the pharmacokinetics of cyclophosphamide and its activated metabolite is observed in an anuric patient. However, an accumulation of toxic, directly alkylating metabolites with a fourfold alkylation rate of plasma proteins is found in this case. Hemodialysis sufficiently eliminated the toxic alkylating metabolites without a measurable influence on the pharmacokinetics of activated cyclophosphamide.

Aged↗
PubMed1979

The air-blood barrier in the human lung. A freeze-fracture study.

The air-blood barrier was studied in replicas of freeze-fractured lung biopsies collected from healthy human subjects. Adjacent pneumocytes display a belt-like network composed of 3-7 superimposed ridges ("fibrils") on the P face and complementary grooves on the E face, i.e., a structure corresponding to a "tight" junction. On the other hand, adjacent capillary endothelial cells show a continuous system of 2-4 membrane foldings. These appear mainly as smooth surfaced crests on the P face; on the E face furrows are seen, at the bottom of which a row of particles is situated. This arrangement suggests a "leaky" type of junction. Discontinuous occluding junctions are located in the pericytic venular segment of the alveolar vessels. The present findings are in agreement with previous physiological and ultrastructural tracer studies locating the main part of the diffusion barrier for small polar solutes and proteins in the alveolar epithelium. Communicating junctions are demonstrated between type I and type II pneumocytes, indicating intercellular cooperation between these cells of common embryonic origin, but which fulfill different functions in the adult. In the endothelium of the non-muscular alveolar vessels communicating junctions are lacking. Desmosomes occur in the epithelium between type I and type II pneumocytes; square arrays of particles characterize the plasma membrane of type I pneumocytes.

Adolescent↗
PubMed1979

Hypercalciuria in idiopathic Fanconi syndrome.

A 9 year old girl with idiopathic Fanconi syndrome and hypercalciuria is described. In order to determine whether the increased calcium excretion was directly or indirectly due to the disturbed phosphate metabolism, the behavior of the calcium excretion during therapy, the serum levels of 1,25-dihydroxyvitamin D and parathyroid hormone, and the effect of parathyroid hormone on the renal tubules were investigated. Normal serum 1,25-dihydroxyvitamin D and parathyroid hormone levels, lack of a correlation between the serum phosphate concentration and the degree of hypercalciuria, as well as unsuccessful therapy of the hypercalciuria with oral phosphate indicate that the increased calcium excretion cannot be explained by impaired renal phosphate reabsorption. The hypercalciuria in the patient was therefore regarded as being due to a primary decrease of tubular calcium reabsorption.

Calcium↗