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Biomedical subjects

P Brenner

Publications and source records attributed to P Brenner.

At least 37 records · Page 2Linked to original sources
PubMed1999

Effects of prolonged cold storage time in xenotransplantation.

BACKGROUND: Ischemia and reperfusion injury after prolonged ischemic time (IT) has a marked influence on hyperacute xenograft rejection (HXR). The aim of the study was to investigate the impact of different cold ischemic times on the HXR of ex vivo "working pig hearts" perfused with human blood. Xenoreactive natural antibodies (XNAb) as the trigger of HXR were reduced by immunoadsorption (IA) using an Ig-Therasorb column. METHODS: Hearts of 24 Landrace pigs (13-31 kg) were harvested after cardioplegia with Celsior-solution and split into 4 groups. In Group C1 (n = 6) the short ischemic time (IT) lasted 48.9+/-10 minutes on the average prior to start of xenoperfusion, in Group I1 IT lasted 4 hours instead. Groups C2 and 12 experienced the same IT as C1 and I1, respectively, but underwent 2 cycles of IA in addition. IA removed immunoglobulins IgG, IgM and IgA from the perfusate. In the working heart mode hemodynamic parameters were measured in defined intervals. Blood samples were collected at the same time to determine myocardial enzymes, immunoglobulins, complement and anti-pig-antibodies. At the end of the study (cardiac arrest) tissue was sampled for histologic examination (light/electron microscopy (LM/EM) and immunohistochemistry). RESULTS: Survival time of the control Group C1 was 125 minutes. IA resulted in an extension of perfusion time to 6.5 hours in C2. Four hours of IT (I1) prolonged the working time of hearts when compared with C1. IA had no additional impact (I2). Heart weight increased significantly in C1 without IA. Cardiac output and coronary flow in C1 were significantly lower when compared with the other 3 groups. IA improved cardiac output (CO) in C2 (vs C1, p < 0.001). Histologic signs of HXR (LM/EM) could be found in C1 in contrast to the other groups. Serologic parameters for myocardial damage were higher in groups with prolonged IT than in groups with short IT. CONCLUSION: Prolonged ischemia and reperfusion injury showed controversial effects in this specific xenogeneic heart transplant model. In contrast to observations in allogeneic transplantation 4 hours of IT showed a beneficial behaviour of the xenografts. Reasons could be either a protective effect of the Celsior solution or changes of the endothelial cell surface (in terms of glycosylation or loss of alpha1-3Gal-epitopes). Tolerance of prolonged IT would allow transportation of xenografts over long distances.

Animals↗
PubMed1998

[Considerations on the management of subtotal and total macro-amputation of the upper extremity].

Between 1982 and 1993, 65 amputation and amputation-like injuries in the upper arm (n = 18), proximal and middle forearm (n = 32) and distal forearm and wrist level (n = 15) were treated in our institution. The overall survival rate in our series was 92.3% (60/65). In 3 of 65 cases early secondary amputation because of vascular failure was necessary. There was one reamputation because of deep infection with beginning sepsis. Severe systemic disturbances were seen in one patients, requiring early reamputation. Twenty-five patients with a follow-up of more than 2 years were reviewed in a retrospective clinical study and evaluated according to the Chen classification. Of 8 patients with upper-arm involvement, 2 had a grade II result, 4 a grade III and 2 a grade IV result. There were 1 grade I, 2 grade II, 2 grade III and 5 grade IV results in the proximal forearm group. In the distal forearm group 2 patients each showed a grade I, II and III result and 1 a grade IV. Taking grades I and II results together, a "functional extremity" could be reconstructed at the upper arm level in 25%, proximal forearm 30%, and the distal forearm in 58%. The main advantage of replantation/revascularization of the upper limb is the possibility of restoring some sensitivity to the hand in addition to partial motor recovery, which always provides twice as much individual motor function as is offered by any type of prosthesis currently available. The higher cost and number of operations needed, as well as the longer postoperative care and longer disability time after replantation/revascularization are nevertheless justified by the significant increase in quality of life.

Adolescent↗
PubMed1998

A community-based clinical selective in end-of-life care.

There is a widespread recognition among medical educators and accreditation organizations that medical students and young physicians lack the competency necessary to care for persons near the end of life. This article describes the institutional and attitudinal barriers to innovation in curriculum design. It then presents and evaluates a 1-month selective for fourth year students that focuses on providing end-of-life care to immigrant populations in community-based home hospice. The selective joined biomedical training in pain management and palliative care, a clinical rotation in home hospice care with an analysis of the way that social and ethnic factors inform and influence end-of-life care.

Journal Article↗
PubMed1998

[Does tissue perfusion after free microvascular tissue transplantation stay autonomous?].

In a prospective study including 60 patients after free latissimus dorsi transfer (FLDT) to the lower leg, we found persistence of pedicle blood flow up to 10 years postoperatively. After uncomplicated FLDT the pedicle supported the flap in all cases, whereas after complicated FLDT (hematoma, thrombosis, infection) we found only 50% of all flaps autonomously perfused by the vascular pedicle.

Adolescent↗
PubMed1998

[Control of the patency of coronary artery bypasses with contrast enhanced magnetic resonance angiography].

Contrast-enhanced 3D magnetic resonance angiography (MRA) has the potential for being a reliable method for CABG visualization and CABG patency determination in early postoperative period. 3D reconstruction was helpful in delineating CABG course and in several cases in detecting stenosis of coronary arteries. Compared to coronary angiography MRA is a non-invasive examination technique without iodine contrast medium and X-ray and is practicable in 30 min with minimal risk and low costs.

Aged↗
PubMed1997

[Enchondroma of the hand. Clinical evaluation study of diagnosis, surgery and functional outcome].

Enchondroma are benign cartilaginous tumors and are localized most often at the site of the phalanges. Between 1982 and 1993 73 patients with monostotic enchondroma and 5 patients with polyostotic enchondroma were operated at our clinic. Clinical signs of monostotic tumors were pathological fracture (38.4%), pain or swelling. Eleven percent of cases were accidental findings. Surgical treatment was performed by complete removal of the tumors and filling the bone cavity with autologous spongiosa taken from the pelvic bones, the elbow, or the radius. Three patients (4.1%) had to be operated a second time due to wound infections and hematoma. In one case Sudeck's dystrophy was diagnosed. One patient (1.4%) developed a recurrent tumor. Our follow-up examination of 65 patients showed that 77% of the patients with monostotic enchondroma achieve very good or good functional long-term results after this operation, but only 40% of the patients with polyostotic enchondroma.

Bone Neoplasms↗
PubMed1997

Thirty years survival after double valve replacement with Starr-Edwards prostheses in aortic and mitral position.

We report about a patient who underwent double valve replacement with two Starr-Edwards prostheses in aortic and mitral position 30 years ago. Under anticoagulation medication he survived 28 years without any valve-related events. In the 29th year he sustained a cerebral infarction from which he recovered, having only a residual left arm paresis. His NYHA functional class today is II-III. Chest X-ray shows a mildly enlarged configuration of the heart, echocardiography reveals no irregularities of the implanted prostheses. We conclude, that the Starr-Edwards valve presents an outstanding standard concerning durability in mechanical valve replacement.

Adult↗
PubMed1997

Timing of free microsurgical tissue transfer for the acute phase of hand injuries.

Because of favourable survival rates in replantation surgery and a high standard of free tissue transfer the interval between injury and microsurgical reconstruction has become gradually shorter. The acute phase can be defined as the interval ranging from emergency procedures within 24 hours to urgent procedures done within 72 hours. Bearing in mind the infection rates that have been reported of 1.5% for the acute phase and 17.5% for the late phase, we should encourage emergency reconstructions. However, in most cases of upper extremity injuries, reconstruction with conventional flaps is possible. Between 1981 and 1995 we did 72 acute post-traumatic free tissue transfers to the upper extremity in our unit within 72 hours (urgently). There were no significant differences in the incidence of infections when acute were compared with urgent procedures. As a result we support the concept of urgent operations. The following advantages are to be considered: urgent operations allow a second look operation, the viability of the extremity can be assessed, and the reconstructive procedure can be planned more precisely. Last but not least, the procedure is done during the day time with better operating conditions.

Hand Injuries↗
PubMed1997

[Rare differential diagnosis of breast tumor. Giant cell tumor of the ribs].

We report a case of a breast tumor. As carcinoma of the breast was suspected, a biopsy was taken and a very rare osteoclastoma originating in the rib was identified. Semimalignant bone tumors tend to recur locally. The symptoms are nonspecific; the initial diagnosis is often made late. To differentiate the diagnosis, one should think about primary and secondary bone diseases and tumors of the organs of the thorax. In our case, the tumor was completely resected, including the ribs, and the defect was covered with a corium plasty. In this way, we are able to save the breast. We discuss different methods for covering chest wall defects.

Bone Neoplasms↗
PubMed1997

[Myocutaneous flap as reliable defect coverage in high grade pelvic decubitus ulcers. Classification, therapeutic concept and presentation of personal patient sample of 16 years].

Infected pelvic pressure sores of Campbell stages IV-VII require soft tissue reconstruction, which means stable, multi-layered filling cover of the defect and reliable prophylaxis of relapse. Myocutaneous flaps meet these conditions well. Depending on the extent and the area of the sore, with predilection for the sacrum, the ischial tuberosity and the femoral trochanter, the gluteus maximus, biceps femoris and tensor fasciae latae muscles are most often used for myocutaneous flaps. Primary sutures, split skin grafts or local fasciocutaneous flaps are often sufficient treatment for smaller, superficial defects. Between 1981 and 1996, 133 patients (average age 50 years) with 212 pelvic pressure sores of all stages were treated in our clinic. After radical decubitus excision with pseudotumor technique and resection of the osseous prominences, one-stage reconstruction of solitary as well as multiple defects was performed with myocutaneous flaps in 135 cases. The postoperative general complication rate for all treatments was about 10-30%. With regard to the muscle flaps, one third healed without any problems, partial flap necrosis occurred in 6% and there was total loss of flap in 2% of all myocutaneous flaps. According to present knowledge, myocutaneous flaps seem to be the most reliable method for definitive covering of deep pelvic pressure sores, independent of the cause of the ulcer.

Adolescent↗
PubMed1996

Demonstration of spiral CT scans and reconstructions of a right atrial myxoma with bilateral pulmonary tumor emboli and a coincidental benign mediastinal thymoma.

A very rare case of a right atrial myxoma with bilateral pulmonary tumor emboli and a coincidental benign mediastinal thymoma is reported. A 52-year-old male patient was admitted with complaints of a single episode of haemoptysis. Spiral CT scans has been performed, the data has been subjected to multiplanar reconstructions and 3-D imaging. They revealed the presence of right mediastinal, right atrial and bilateral intrapulmonary masses. The tumors were removed during cardiopulmonary bypass surgery without any complications. All masses appeared to be benign under histopathological and immunohistochemical examinations. This case has been reported since the simultaneous appearance of such masses is unusual and in order to demonstrate that multi-planar and 3-D reconstructions of spiral CT data can help to clarify the anatomical relationships of tumorous masses and there-by a benign etiology of the intracardiac mass has been inferred.

Cardiopulmonary Bypass↗
PubMed1996

Technetium-99m human immunoglobulin (HIG): a new substance for scintigraphic detection of bone and joint infections.

Technetium (99m-Tc)-labelled, polyclonal human immunoglobulin (HIG) has been described as a new agent to detect local infection and inflammation. In this study, we tested 99m-Tc HIG in 55 patients with suspected chronic (n = 42) and acute (n = 13) skeletal infection. Diagnosis was proven operatively (n = 44) and clinically (n = 11), including microbiological culture tests (n = 46). A gamma camera scan was performed 4 and 24 hours after I.v. injection of 500 MBq 99m-Tc-HIG. 99m-Tc-HIG scanning achieved a sensitivity of 91% and a specificity of 93%. We found one false negative and five false positive scintigraphic results in 55 patients. No clinical or biochemical side effects were encountered after 99m-Tc-HIG injection. We recommend this technique especially for localisation of low-grade, chronic osteomyelitis. The mechanisms and kinetics of 99m-Tc-HIG, however, are worth investigating more extensively.

Acute Disease↗
PubMed1996

[Expression of various monoclonal antibodies in nodules and band stage in Dupuytren's disease].

In 42 seronegative patients (n = 6 normal fascia, n = 12 nodal stage of Dupuytren's contracture, n = 24 stage IV) we performed immunohistochemical examinations of specimens of four locations of the digitopalmar fascia by means of indirect immunofluorescence tests. We determined the expression of monoclonal antibodies against vimentin, leucocyte common antigen (LCA, CD 45), four macrophage-antigens (27E10, RM3/1, 25F9, CD68), PDGFR-beta subunit (platelet-derived growth factor receptor). In 12 specimens of nodal stage disease macrophage-antigens typical for late inflammatory phase was detected. Other macrophage phenotypes were found to a lesser degree. All of these antigens were negative in normal palmar fascia and only sporadically positive in stage IV disease. PDGFR, which has not been investigated in digitopalmar flexion contracture before, has been expressed in cells of Dupuytren's disease as well as in normal fascia to a minor degree. In nodal stage disease, PDGFR-expression was not generally increased, although the majority of these cases showed intensively dyed clusters. EGFR could neither be detected in nodal or cord-stage of Dupuytren's disease, nor in normal digitopalmar fascia.

Antibodies, Monoclonal↗