Search PubMed⌕ Search

Biomedical subjects

M Jakob

Publications and source records attributed to M Jakob.

65 records · Page 4Linked to original sources
PubMed1976

Studies on the immune status of children with acute lymphocytic leukaemia. I. Early phase before and after first remission.

Seventeen children of 2-15 years of age with newly diagnosed untreated acute lymphatic leukaemia (ALL) were evaluated with a number of immunological tests: for humoral immunity serum immunoglobulins and reactive antibody formation against three antigens (diphtheria, tetanus, KLH); for cell-mediated immunity in vitro response of blood lymphocytes against PHA; membrane characteristics of blood lymphocytes and lymphoid blasts for both B and T cells. The tests were repeated in thirteen patients who attained full remission. In the majority (twelve cases) no surface markers were detected (null-cell leukaemia), one patient fulfilled the criteria for a T-cell leukaemia with thymoma. Four patients had rather high absolute B-cell counts, but did not fulfill all the criteria for B-cell leukaemia; three of them died before remission. Immune globulin concentrations were only slightly changed, antibody formation, both primary and anamnestic, was possible. PHA response was extremely low in the initial phase, but normal immediately after remission. During remission all patients were markedly depleted in both their B- and T-cell compartment.

Adolescent↗
PubMed1976

Studies on the immune status of children with acute lymphocytic leukaemia. II. In remission with and without cytostatic treatment.

In eleven children with acute lymphocytic leukaemia (ALL), cytostatic treatment was stopped after sustained remission lasting for 9 months--6 1/2 years. Their immunological status was monitored every 6--12 weeks during the first year after cessation of therapy. Rebound of depressed parameters was observed for absolute lymphocyte, B-cell and T-cell counts and for immunoglobulins. A simple follow-up scheme for such patients is proposed.

Antibody Formation↗
PubMed1975

Vitamin B12 transport in blood. I. Congenital deficiency of transcobalamin II.

Some characteristics of vitamin B12 binding and transport in the serum of an infant with congenital hereditary transcobalamin II (TC II) deficiency were studied using the following parameters and methods: vitamin B12 level and binding capacity; electrophoretic mobility in polyacrylamide gel electrophoresis; various immunodiffusion and absorption experiments, using a specific anti-TC II antiserum and the patient's serum as antigen. The results of these studies point to a deficient synthesis of TC II. Parenteral administration of high doses of vitamin B12 was followed by rapid and complete clinical remission and the appearance of vitamin B12 binder in the alpha 2 region which is similar to "fetal binder." Thus, very high concentrations of vitamin B12, either carrier free or bound to this alpha 2 binder, were able to correct the disturbed physiology of TC II deficiency, presumably by normalization of DNA-thymine synthesis.

Humans↗
PubMedDate not supplied

Coronary pseudoaneurysm: diagnosis by intravascular ultrasonography.

A pseudoaneurysm after percutaneous coronary angioplasty (PTCA) of the left anterior descending coronary artery is reported in a 52-year-old woman who underwent PTCA for exertional angina and a significant isolated stenosis of the left anterior descending coronary artery. Intravascular ultrasonography during repeat coronary angiography clearly identified a localized coronary dilation at the PTCA site in conventional coronary angiography as a pseudoaneurysm that was confirmed during surgery.

Aneurysm, False↗
PubMedDate not supplied

Mosaicism of dynein in spermatozoa and cilia and fibrous sheath aberrations in an infertile man.

Male patients displaying an immotile or almost immotile sperm population are the object of an interdisciplinary study concerning a ciliary mutant that induces the "Immotile-Cilia Syndrome". Development and function of both sperm flagella and cilia are normally affected because of disturbances of the 9 + 2-arrangement. During this program, clinical, physiological, genetical and ultrastructural investigations were done. The ultrastructure of immotile spermatozoa of an infertile man did not reveal inner and outer dynein arms. Lack of the ATPase dynein which is essential for movement of the 9 + 2-axoneme, is typical for the above syndrome. In addition, symmetry of the fibrous sheath of the spermatozoa was very abnormal. The pneumologist examined normal lung function, where the ultrastructure of the cilia of the nasal mucosa displayed the dynein arms. Analysis of family tree and chromosomes by the geneticist also gave a normal result. As revealed by this infertile patient it seems likely that expression of dynein must not be identical in both germ cells and somatic cells. Such variations are therefore regarded as additional forms of the "Immotile-Cilia syndrome". Asymmetric fibrous sheaths are thought to be a result of immotile spermatid flagella, leading to an abnormal arrangement of the accessory axonemal structures. Normal early spermatid flagella of man and rat show specific movements.

Adenosine Triphosphatases↗
PubMedDate not supplied

Uniform tissues engineered by seeding and culturing cells in 3D scaffolds under perfusion at defined oxygen tensions.

In this work, we assessed whether culture of uniformly seeded chondrocytes under direct perfusion, which supplies the cells with normoxic oxygen levels, can maintain a uniform distribution of viable cells throughout porous scaffolds several milimeters in thickness, and support the development of uniform tissue grafts. An integrated bioreactor system was first developed to streamline the steps of perfusion cell seeding of porous scaffolds and perfusion culture of the cell-seeded scaffolds. Oxygen tensions in perfused constructs were monitored by in-line oxygen sensors incorporated at the construct inlet and outlet. Adult human articular chondrocytes were perfusion-seeded into 4.5 mm thick foam scaffolds at a rate of 1 mm/s. Cell-seeded foams were then either cultured statically in dishes or further cultured under perfusion at a rate of 100 microm/s for 2 weeks. Following perfusion seeding, viable cells were uniformly distributed throughout the foams. Constructs subsequently cultured statically were highly heterogeneous, with cells and matrix concentrated at the construct periphery. In contrast, constructs cultured under perfusion were highly homogeneous, with uniform distributions of cells and matrix. Oxygen tensions of the perfused medium were maintained near normoxic levels (inlet congruent with 20%, outlet > 15%) at all times of culture. We have demonstrated that perfusion culture of cells seeded uniformly within porous scaffolds, at a flow rate maintaining a homogeneous oxygen supply, supports the development of uniform engineering tissue grafts of clinically relevant thicknesses.

Adult↗
PubMedDate not supplied

Bi-zonal cartilaginous tissues engineered in a rotary cell culture system.

In this study, we aimed at validating a rotary cell culture system (RCCS) bioreactor with medium recirculation and external oxygenation, for cartilage tissue engineering. Primary bovine and human culture-expanded chondrocytes were seeded into non-woven meshes of esterified hyaluronan (HYAFF-11), and the resulting constructs were cultured statically or in the RCCS, in the presence of insulin and TGFbeta3, for up to 4 weeks. Culture in the RCCS did not induce significant differences in the contents of glycosaminoglycans (GAG) and collagen deposited, but markedly affected their distribution. In contrast to statically grown tissues, engineered cartilage cultured in the RCCS had a bi-zonal structure, consisting of an outgrowing fibrous capsule deficient in GAG and rich in collagen, and an inner region more positively stained for GAG. Structurally, trends were similar using primary bovine or expanded human chondrocytes, although the human cells deposited inferior amounts of matrix. The use of the presented RCCS, in conjunction with the described medium composition, has the potential to generate bi-zonal tissues with features qualitatively resembling the native meniscus.

Adult↗