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B Hermanns

Publications and source records attributed to B Hermanns.

31 records · Page 2Linked to original sources
PubMed1999

Hypoxic Hypoperfusion Fails to Induce Myocardial Hibernation in Anesthetized Swine.

BACKGROUND: Congenital origin of the left coronary artery from the pulmonary artery (ALCAPA) results in chronically dysfunctional myocardium with the partial ability to recover after revascularization. We attempted to establish an ALCAPA syndrome in anesthetized pigs for 24 hours and to compare it with stunned and infarcted myocardium. METHODS AND RESULTS: In group 1 (n = 12), a bypass graft was interposed between the pulmonary artery and the left anterior descending coronary artery (LAD). Reduction of flow in the LAD with gradual increases in flow from the pulmonary artery resulted in an incremental reduction of segment shortening (8.9 +/- 5.3% at 24 hours vs 26.6 +/- 10% at baseline, P <.005). In group 3 (n = 5), 2 cycles of 10-minute LAD occlusion resulted in decreased segment shortening with slow recovery (at 24 hours 18.7 +/- 1.3% vs 24.2 +/- 4% at baseline, segment shortening with slow recovery (at 24 hours 18.7 +/- 1.3% vs 24.2 +/- 4% at baseline, P <.05). In group 3 (n = 6), 1-hour LAD occlusion reduced segment shortening at 24 hours to 4.7 +/- 5.2% (P <.005 vs baseline). Histological analysis of the LAD territory revealed severe degeneration, myolysis, and alteration of the chromatin structure in group 1 comparable to ischemic cell death in group 3, whereas control areas and the LAD area in group 2 showed only minor structural alterations. Infarct size/risk area, as measured by tetrazolium staining, was 49.8 +/- 11.2% in group 1, 9.3 +/- 8.1% in group 2 (P <.005), and 60.3 +/- 9% in group 3. CONCLUSION: Hypoxic myocardial hypoperfusion from the pulmonary artery results in myocardial necrosis in anesthetized pigs. These findings are in contrast to the concept of myocardial hibernation in the ALCAPA syndrome because in this model, hypoxic hypoperfusion failed to induce adaptation to preserve myocardial structure.

Journal Article↗
PubMed1998

Coronary vasculopathy in polycythemia vera.

Thrombosis is a common complication in polycythemia often causing death. In coronary artery occlusion, thrombosis due to hyperviscosity and thrombocytosis is mostly discussed as the origin of the infarction. We discuss the case of a 30-year-old male patient, with polycythemia, who died of myocardial infarction. On autopsy the vessels showed neither ateriosclerotic changes nor thrombotic occlusions. Instead, a marked intima proliferation was found leading to multiple occlusions whereas media and adventitia were unchanged. This pattern of a coronary vasculopathy has not been described before, and can be interpreted as an alternative mechanism for vascular occlusion in polycythemia. Similar histopathological changes have already been found in skin lesions in erythromelalgia, a common symptom in polycythemia.

Adult↗
PubMed1998

Pathomorphological aspects of heparin-induced thrombocytopenia II (HIT-II syndrome).

The therapeutic use of heparin results in thrombocytopenia in 5-30% of patients. In 0.1-1% of patients treated with heparin, the platelet count decreases to between 100 x 10(9)/l and 50 x 10(9)/l and leads to severe synchronous central arterial and venous thrombosis with a mortality of 18-36%. This is known as "white-clot syndrome" or heparin-induced thrombocytopenia II (HIT-II syndrome). Whilst the clinical aspects and the central type of thrombosis in HIT-II syndrome are well documented, the histomorphology and differential diagnosis of thrombosis are not. We report three cases of HIT-II syndrome with thrombosis of the central arteries and veins. The HIT-II thrombi could be differentiated from thrombi of other origins, particularly from mural thrombi. Heparin-induced thrombi were seen on microscopical examination to be like onion skin in structure, and immunohistochemistry showed that they had a markedly reduced content of fibrin and clearly enhanced amounts of IgG and IgM. The layered structure thus implied appositional growth. The thrombi in HIT-II syndrome do not seem to be induced by activation of the coagulation cascade, but by platelet aggregation mediated by anti-platelet antibodies.

Aged↗
PubMed1998

[Ultrastructural differential diagnosis of gastrointestinal stromal tumors].

Gastrointestinal stromal tumors (GIST) may present with myogen or neurogen differentiation, mixed differentiation or with morphological features which cannot be further specified. 14 GIST of the stomach (9), the duodenum (2) and small bowel (3) were examined by immunohistochemistry and electron microscopy. Diagnosis was consistent for such tumors located distally from the stomach, however, evaluation of GIST of the stomach was different (apart from one case). Light microscopy and immunohistochemistry did not allow to discriminate between the different subtypes of GIST, however, electron microscopy revealed cellular differentiation. Hence, ultrastructural analysis is an useful tool for diagnosis of GIST, particularly those of the stomach.

Adult↗
PubMed1998

Cytogenetic and morphologic characteristics of gastrointestinal stromal tumors. Recurrent rearrangement of chromosome 1 and losses of chromosomes 14 and 22 as common anomalies.

We present cytogenetic findings in five gastrointestinal stromal tumors (GISTs). Three of these five cases had abnormal karyotypes with clonal chromosomal aberrations. The most common karyotypic pattern was a combined loss of chromosomes 14 and 22 in a total of three cases. Among these cases, additional recurrent chromosomal abnormalities were loss of 1p and/or 9, detected in two cases each. Another karyotypic feature consisted of polyploidisation, leading to hypotetraploid chromosome numbers in one case. These cytogenetic results provide evidence for a characteristic karyotypic pattern consisting of -14 and -22 in a subset of GISTs.

Chromosome Aberrations↗
PubMed1997

The Cantrell-sequence: a result of maternal exposure to aminopropionitriles?

The characteristic features of the Cantrell-sequence--anterior thoraco-abdominal wall defect with ectopia cordis and diaphragm, sternum, pericardium, and heart defects--have been observed in animals following maternal administration of beta-aminopropionitrile, a toxic amino-acid derivative. We report on an unusual case of the Cantrell-sequence in a premature infant with associated dysmelia, aplasia of the right kidney, cerebellar hypoplasia and circumscribed aplasia of the cutis, which has not been reported previously. Maternal history suggested an occupational exposure to aminopropionitriles prior to pregnancy. Prenatal ultrasound, differential diagnosis, perinatal management, and the teratogenic role of aminopropionitriles in this rare genetic disorder are discussed.

Abnormalities, Multiple↗
PubMed1996

[HELLP syndrome in the 21st week of pregnancy in mosaic trisomy 9].

We report for the first time the case of postabortional HELLP-syndrome in the 21st week of gestation. In this case mosaic trisomy 9 was confirmed by amniocentesis prior to induction. Pertinent history, clinical course and pathoanatomical morphology are described. We emphasize the early onset of the HELLP-syndrome in association with trisomy 9 after abortion. The possibility of interconnections between trisomy 9 and the occurrence of HELLP-syndrome (sparse blood, vessels in the villi, circulatory deficit on the fetal side of the placenta, increased production of e.g. vasopressive substances) is discussed.

Abortion, Eugenic↗
PubMed1980

Ophthalmodynamic studies in kinking of the internal carotid artery. Surgical implications.

In 6 patients with kinking of the internal carotid artery and 10 healthy volunteers ophthalmodynamographic studies were performed. Sideward head bending in the patients caused major ipsilateral decrease of internal carotid flow as did forward flexion on both sides. This effect was minimal in healthy humans. Intraoperative monitoring by the same method showed instant improvement of flow dynamics after kink resection and end-to-end anastomosis.

Adult↗
PubMedDate not supplied

[Recurrent pigmented villonodular synovitis (PVNS)].

AIM: The pigmented vilionodular synovitis (PVNS) is a tumour like disease of unknown origin that often shows recurrence. The pathogenesis is still unknown and therefore the question of the right therapy is not resolved. MATERIAL: With a case report of a patient with recurrence after two arthroscopic synovectomies, PVNS is discussed against the background of the clinical, histological, and radiological features. RESULTS: We performed an open synovectomy and cystic lesions in both condyles of the femur and proximal tibia were filled with homologous and autologous cancellous bone. Three months later the patient had no pain and the bone density in the former cystic lesions was appropriate. DISCUSSION: The pathogenesis is still unknown. Diagnosis often is obtained much too late due to missing specific symptoms. PVNS occurs in local forms as well as in a diffuse growth pattern. Recurrence rates of up to 78% are very high. Besides arthroscopic and open synovectomy, the treatment with radiosynoviorthesis must be considered. Depending on the growth pattern, the tumour masses, and the affected joint, the therapy has to be chosen very carefully and sometimes different forms have to be combined if a recurrence--free result is to be achieved.

Adult↗
PubMedDate not supplied

[First experiences with fluorodeoxyglucose-positron-emission tomography (FDG-PET) in the evaluation of painful total knee and hip joint replacements].

AIM: The aim of the study was to describe first experiences using FDG-PET in the examination of painful arthroplasties. METHOD: 12 patients prior to revision of a total hip or knee joint replacement underwent PET. Histopathology, microbiological analysis and intraoperative diagnosis were compared to preoperative PET findings. RESULTS: The analysis of intraoperative findings, of microbiological examinations and of histopathology showed that besides the well known determinants infection and early postoperative granulation tissue, polyethylene wear induced foreign-body reaction was a major cause for increased FDG consumption. CONCLUSION: In vivo imaging of marked foreign-body tissue reaction induced by polyethylene wear is feasible by FDG-PET. This observation, however, leads to reduced specificity of PET imaging for the diagnosis of periprosthetic infection.

Aged↗
PubMedDate not supplied

[[F-18]-fluorodeoxyglucose (FDG) positron emission tomography (PET) as a diagnostic for hip endoprosthesis loosening].

AIM: The purpose of this study was to examine the FDG-PET in respect of its diagnostic valency with regard to septic/aseptic loosening of lower limb prostheses. METHOD: 28 patients with 41 lower limb prostheses were examined by means of FDG-PET to evaluate septic/aseptic loosening of their hip prostheses. Therefore, a differentiated FDG-PET result interpretation subdivided into five categories was developed. The final diagnosis was based on operative findings with following culture and histological outcome. RESULTS: The worked-out categories showed a high agreement to the intraoperative macroscopic and histological results (n = 23 correctly positive, n = 1 false positive, n = 1 correctly negative and n = 3 false negative). CONCLUSION: With a subtly differentiated interpretation (categories I - V) of the qualitative glucose metabolism safe statements can be made regarding septic/aseptic endoprostheses loosening. This was impressively confirmed by the agreement of the FDG results with the histological results.

Aged↗
PubMedDate not supplied

Differential diagnosis, prognostic factors, and clinical treatment of proliferative Brenner tumor of the ovary.

Brenner tumors are rare ovarian tumors displaying benign, borderline or proliferative, and malignant variants. The case of a 63-year-old woman with a proliferative Brenner tumor is presented and the histomorphological differential diagnosis of this tumor entity is compared to that of its benign and malignant counterparts. Light microscopy, immunohistochemistry, and electron microscopy were performed to allow discrimination from the other subtypes. Despite a considerable overlap of pathological features the differential diagnosis of proliferative Brenner tumor could be established. Electron microscopy allowed assessment of characteristic infoldings of the nuclear membrane that proved to be a valuable ultrastructural criterion. Considering that the vast majority of Brenner tumors are benign, precise identification of the small proportion of malignant tumors allows the extent of surgical therapy to be adapted.

Biomarkers, Tumor↗