Search PubMed⌕ Search

Biomedical subjects

M Blank

Publications and source records attributed to M Blank.

At least 307 records · Page 17Linked to original sources
PubMedDate not supplied

The effect of alpha-fetoprotein on the growth of placental cells in vitro.

Cell cultures of early mouse placentae were studied in the presence of mouse amniotic fluid or isolated alpha-fetoprotein (AFP). Four cell types were observed: polygonal cells, giant cells, small round cells and fibroblasts. The number of polygonal cells increased in placental cultures in the presence of amniotic fluid or AFP, suggesting de novo formation and proliferation in vitro. These preparations were found to stimulate the DNA synthesis in polygonal cells, as demonstrated by 3H-thymidine labelling experiments. Polygonal cells also show a significant increase in 3H-leucine incorporation, indicating more active protein synthesis under the effect of amniotic fluid or AFP. These data suggest that AFP may be one of the fetal factors promoting trophoblastic differentiation.

Amniotic Fluid↗
PubMedDate not supplied

Perspective volume rendered motion: gaining insights virtually.

Since modern imaging modalities deliver huge amounts of data the visualization techniques utilized must emphasize the structures of interest. To compare them, the different visualization techniques are regressed to a common ground whereby their strengths and weaknesses can be revealed. Perspective, lighting, color and motion support the real world look and feel. Virtual 3D techniques allow the observer to move through 3D images of anatomy almost in real time. In virtual cisternoscopy this concept is applied to 3D data of the head to reveal a closer look at the cerebral vessels. The more realistic presentation of the 3D data allows for higher efficiency.

Brain↗
PubMedDate not supplied

MR diagnosis of vein of Galen aneurysmal malformations using virtual cisternoscopy.

Vein of Galen aneurysmal malformations (VGAMs) are rarely seen intracranial congenital vascular malformations with extremely complex vascular architectures. We present two newborns with an unclear intracranial mass being discovered in routine intrauterine ultrasonography. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) identified these lesions as VGAMs. Besides conventional MRA analysis, "virtual cisternoscopy"-a special kind of virtual endoscopy combining perspective volume rendering and motion-was applied to assess the intracranial vasculature. One newborn was treated by means of interventional neuroradiology with coiling of the median prosencephalic vein. The clinical outcome in this case was excellent. The other will undergo interventional therapy shortly.

Cerebral Veins↗
PubMedDate not supplied

Anatomic variation of the coracoacromial ligament: a macroscopic and microscopic cadaveric study.

The operative management of the subacromial impingement syndrome includes reconstruction in cases with ruptured tendons and enlargement of the subacromial space by arthroscopic or open resection of the coracoacromial ligament and acromioplasty. In nearly 20% of all cases, however, surgical treatment fails. This study was conducted with 124 cadaver shoulders of older specimens with a balanced male/female ratio. The coracoacromial ligament did not present homogenous morphologic characteristics. We found 25.8% of all ligaments undivided, 59.7% bipartite, and 14.5% consisted of three parts. The third part, located most medially, took a hidden path to the coracoid process and was not visible during dissection until after the clavicle was resected. This medially situated third part of the coracoacromial ligament has not been described in the medical literature before the time of our investigation. It could well be responsible for persisting subacromial pain after surgery, if it is not identified and resected during surgery.

Acromion↗
PubMedDate not supplied

[Luliberin analogues exhibiting a cytotoxic effect on tumor cells in vitro].

Luliberin analogues modified at the N-terminus were synthesized to search for drugs exerting a cytotoxic effect on cells of hormone-dependent tumors. A synthetic scheme effective in the preparation of analogues containing fatty acid residues was proposed. The cytotoxic effect of the peptides was studied on a number of cell lines of human tumors in vitro. The dependence of the antitumor effect on the length of peptide chain, amino acid sequence, and structure of the N-terminal group was demonstrated. Modification with palmitic acid was found to result in highly active compounds in the case of analogues containing more than ten aa, whereas modifications with lauric, caproic, or trimethylacetic acid led to compounds with significantly lower activities. Analogues of luliberin containing a palmitic acid residue and effectively inhibiting the growth of tumor cells in vitro were synthesized.

Amino Acid Sequence↗
PubMedDate not supplied

Enhanced circasemiseptan (about 3.5-day) variation in the heart rate of cancer patients?

In addition to prominent circadian and circannual components, an about half-weekly (circasemiseptan) pattern was shown earlier to characterize mitotic activity in cancer patients. A circasemiseptan variation in heart rate and circadian rhythms in heart rate and axillary temperature of cancer patients are assessed herein. These variables could be tested as putative marker rhythms for the optimization of radio- and/or chemotherapy by timing which, from a practical viewpoint, may be easier to implement along the scale of the week than that of the day.

Adolescent↗
PubMedDate not supplied

Anti-cardiolipin antibody from a patient with antiphospholipid syndrome (APS) recognizes only an epitope expressed by cardiolipin/beta 2-glycoprotein-I (beta 2GPI) complex and induces APS.

OBJECTIVE: As the antiphospholipid syndrome (APS) is characterized by antibodies which bind negatively charged phospholipids either directly or mainly through different target epitopes located on the beta-2-glycoprotein-I (beta 2GPI) molecule, the aim of this study is to describe an additional target epitope for anti-cardiolipin binding. METHODS: The binding characteristics of affinity purified anti-cardiolipin antibodies from a patient with monoclonal gammopathy associated with clinically overt APS were studied; inhibition studies were also carried out. These antibodies were used for the active induction of experimental APS. RESULTS: The affinity purified anti-cardiolipin antibodies were found to bind a target epitope created by the complex of cardiolipin/beta 2GPI, while not reacting with a complex composed by another phospholipid (phosphatidylserine/beta 2GPI), as confirmed by direct binding and competition assays. Immunization of naive mice with this unique affinity purified anti-cardiolipin antibody resulted in the induction of experimental APS (thrombocytopenia, prolonged coagulation timed and fetal resorptions). The anti-cardiolipin/beta 2GPI injected mice developed high titers of mouse anti-cardiolipin/beta 2GPI antibodies with the same binding characteristics as the human antibody which was used for disease induction. CONCLUSION: APS is a unique syndrome that is characterized by a diversity of pathogenic anti-phospholipid antibodies which may explain the diversity of clinical manifestations reported in patients.

Aged↗