Search PubMed⌕ Search

Biomedical subjects

J Bier

Publications and source records attributed to J Bier.

At least 55 records · Page 3Linked to original sources
PubMed1995

Human immunodeficiency virus-associated squamous cell carcinomas of the head and neck presenting as oral and primary intraosseous squamous cell carcinomas.

Six cases of squamous cell carcinoma arising in the head and neck of patients infected with the human immunodeficiency virus are described. This article reports the first two cases of primary intraosseous squamous cell carcinoma associated with infection with human immunodeficiency virus. Clinical presentation, results of imaging studies, histologic characteristics, therapies applied, and the clinical follow-up are described in detail for each of the six cases. These data are evaluated through a review of the current literature.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Venous graft as temporary arteriovenous shunt in free tissue transfer.

A new method of interpositional venous graft in microvascular tissue transfer is described. The interpositional vein is transferred to the vessels of the recipient site primarily, forming an arteriovenous shunt. Later, when the microanastomosis to the flap is created, the shunt is divided into an arterial branch and a venous branch. This method reduces the ischemic time of the free flap and allows the use of interpositional grafts of optimal length.

Arm↗
PubMed1994

Radioimmunoscintigraphy of squamous cell carcinoma in the head and neck region.

Radioimmunoscintigraphy (RIS) with a monoclonal antibody (SQ 174, Biomira, Inc, Canada) is introduced as a new diagnostic method for detection of squamous cell carcinoma in the head and neck region. RIS could detect eight of the 10 primary tumors. One patient had histopathologically proven nodal disease. This lymph node was seen in RIS. No false positive results were seen in RIS, whereas sonography, computed tomography, and magnetic resonance imaging showed several false positive results.

Aged↗
PubMed1994

Value of magnetic resonance imaging in staging carcinomas of the oral cavity and oropharynx.

The value of magnetic resonance imaging (MRI) in preoperative tumor (T) staging was assessed prospectively in 46 patients with malignant carcinomas of the oropharynx and oral cavity. In each case, the MRI findings were compared with the preoperative clinical and postoperative histopathologic findings. MRI showed an accuracy of 89% in identifying the T stage, as compared with the histopathologic result. The accuracy of the clinical examination was 78%. Compared with the clinical examination, MRI is particularly suited for differentiating T3/T4 and the larger T2 tumors. MRI tends to overinterpret the T stage when the neighboring tissues are inflamed or edematous, as it allows no demarcation between inflamed or edematous tissue and tumor. Moreover, normal oropharyngeal mucous membrane and intrinsic tongue muscle both absorb contrast medium. In the clinical examination, the T stage is often underestimated, as the depth of infiltration and bone involvement cannot always be determined with certainty. The ability of MRI to give an axial, coronal, and sagittal image allows an exact preoperative view of tumor spread and assessment of infiltration into adjacent structures.

Adult↗
PubMed1994

Microsurgical and prosthetic reconstruction of patient with recurrent ameloblastoma extending into the skull base.

A patient with recurrent ameloblastoma extending into the skull base is presented. An interdisciplinary treatment strategy is described, which included proper diagnosis by computed tomography (CT) and magnetic resonance imaging (MRI) scans and radical resection of the tumor in cooperation with the neurosurgeon, followed by reconstruction with microsurgical methods, and prosthetic rehabilitation based on an implant-supported epithesis.

Ameloblastoma↗
PubMed1994

Adaptive responses of coronary circulation and myocardium to chronic reduction in perfusion pressure and flow.

We tested the hypothesis that chronic reduction in perfusion pressure and flow in the coronary circulation induces a state of myocardial "hibernation" characterized not only by a steady-state reduction in myocardial O2 consumption (MVO2) but also by evidence of persistent dilator reserve of the distal vasculature. Biochemical and morphological changes in the coronary vasculature were also assessed. Experiments were conducted in swine with an extraluminal coronary stenosis placed 4-32 wk before study. Stenosis reduced lumen diameter by approximately 80% at the time of final experimentation. Baseline, regional myocardial blood flow distal to the stenosis in both endocardial and epicardial layers was reduced vs. that of the normal zone. Vasodilator reserve persisted in both endocardial and epicardial layers of the stenosis zone. Flow increased in each layer in response to adenosine plus phenylephrine and failed to decline despite a marked reduction in perfusion pressure in response to adenosine alone. Regional MVO2 at baseline was reduced vs. historical controls without coronary stenosis. Protein synthesis rate in coronary vessels of the stenosis zone was reduced vs. that of the normal zone. Morphological responses of stenosis zone vessel walls were heterogeneous. Smaller microvessels exhibited mild hypertrophy of their walls, whereas walls of larger microvessels tended to atrophy. Thus chronic reduction in perfusion pressure and flow induces a state of myocardial hibernation characterized by a steady-state reduction in MVO2 in association with persistent dilator capacity. Biochemical and morphological changes occur in microvessel walls and may contribute to observed physiological responses.

Acclimatization↗
PubMed1994

[A dental CT study for preoperative assessment of maxillary atrophy].

According to a new technology in the planning of endo-osseous implantation, based on a new CT-software for evaluation of the bone structure of the jaws, anatomico-morphological changes after the loss of teeth are measured much more accurately than with conventional methods like the panoramic intraoral x-ray or conventional tomography. 30 mandibles and 22 maxillae of 36 patients were examined. Besides the topographic course of the mandibular canal and the location of the foramen mentale, the anatomic structures as the important aspects for planning endo-osseous implants are seen more accurately. It is now possible to recognise morphological changes with paraxial reconstructions in a very short time more clearly and precisely than with former techniques.

Adult↗
PubMed1993

A comparison of radical and conservative neck dissection.

A review is presented of the confusing terminology applied to the various types of neck dissection. It is recommended that the terms "conservative" and "radical" be based on clear definitions. The fourth prospective, randomized DOSAK therapy study deals with the controversial issue of radical as compared with conservative neck dissection. Patients with squamous cell carcinoma (SCC) of the oral cavity who had not been treated before were randomized and stratified according to the DOSAK treatment-dependent prognostic index (TPI). At present, 104 patients have been evaluated, of whom 48 had radical neck dissection, and 56 conservative neck dissection. Tumor location and patient age and sex are equally divided in both therapy groups. After an average follow-up time of 460 days, the relative mortality for both therapy groups is 23%. At this stage, there is no difference between the two groups in the percentage of patients with complete remission or in the percentage of patients alive. At this stage, there appears to be no difference between the two groups with regard to patient survival or recurrent disease.

Carcinoma, Squamous Cell↗
PubMed1991

Origin of anterior interventricular vein blood in domestic swine.

This study tested the hypothesis that anterior interventricular vein effluent of domestic swine is composed primarily of blood draining the perfusion territory of the left anterior descending coronary artery. As a corollary, the extent to which circumflex and right coronary inflow contributes to anterior interventricular vein outflow also was determined. Experiments were conducted in vitro with buffer-perfused swine hearts in which anterior interventricular vein flow was measured under various combinations of left anterior descending and circumflex coronary perfusion. Studies also were performed in vivo in different groups of intact swine with normal, stenosed, and occluded left anterior descending coronary artery. The results of the study confirm the hypothesis and demonstrate under a variety of conditions that at least 90% of anterior interventricular vein effluent is derived from blood originating from myocardium perfused by the left anterior descending coronary artery.

Animals↗
PubMed1990

The serratus anterior osteocutaneous free flap.

Microvascular transfer of the rib as an osteocutaneous or osseous free flap based on the thoracic branch of the thoracodorsal artery is described. A review of the literature revealed various patterns of rib vascularization in different areas of the body from the periosteum and the endosteal vessels. Reversing the blood flow in the transcortical vessels of the rib is reported to be possible. Injection studies showed a reliable connection between the thoracic branch of the thoracodorsal artery and the endosteal vessels of the sixth and seventh ribs at the origin of the anterior serratus muscle. This approach to free rib transfer has proved to be quick, easy, and reliable in various clinical applications.

Adult↗
PubMed1989

Postoperative active-specific immunotherapy of lymph node micrometastasis in a guinea pig tumor model.

Strain 2 guinea pigs bearing the transplanted intradermally growing line 10 tumor underwent surgical tumor excision at a time when the tumor had already metastasized to the first draining lymph node. Postoperative active-specific immunotherapy (ASI) consisted of two vaccinations with either Newcastle disease virus (NDV) modified or BCG-admixed line 10 tumor cells. 32% of the animals were cured of residual lymphatic micrometastasis by ASI with NDV-modified tumor cells while ASI with BCG was successful in 45%. No synergistic effect was observed when both ASI procedures were combined. Vaccine preparations with mitomycin C inactivated tumor cells proved to be less (NDV) or noneffective (BCG) compared to those with irradiated tumor cells.

Animals↗