[Secondary glaucoma in hyphema, hypopyon, iris prominence and iris hyperemia].
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Biomedical subjects
Publications and source records attributed to H Radner.
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BACKGROUND: ABO blood group antigens are only expressed by the epithelial cells of normal human corneas. Since AB0 blood group antigens are also known to be expressed on stromal and endothelial cells of inflamed corneas, this study aimed to investigate the extend of ABO blood group antigen expression in corneal allograft failures. MATERIAL AND METHODS: Twenty-two failed corneal allografts of 22 patients were examined. In 12 cases the patients had clinically proven corneal allograft rejection. In 10 cases there was no evident history of allograft rejection and the diagnosis graft failure due to chronic endothelial cell loss was made. Immunohistochemical staining of paraffin embedded sections was performed with monoclonal mouse antibodies to human blood group antigen A or B using the streptavidin-biotin-peroxidase complex technique. RESULTS: Blood group antigens A or B were expressed by stromal keratocytes in 5 out of 12 and by endothelial cells in 7 out of 12 corneas with clinically proven immunologic graft rejection. Corneal transplants with chronic endothelial cell loss expressed blood group antigens A and/or B on the endothelial cells in three out of ten cases. CONCLUSION: The results of this study show that ABO blood group antigens can be up-regulated in cases of corneal allograft failure, especially in cases of immune mediated graft rejection. This phenomenon might play a role in corneal allograft rejection.
In this report we describe the case of a testicular schwannoma in a human. Histologically, the tumor presented as a plexiform schwannoma. This rare benign peripheral nerve sheath tumor is an uncommon nodular variant of schwannoma, which mimics plexiform neurofibroma by its multinodular growth.
New developments in neuro-oncology have prompted an update of the World Health Organization (WHO) classification of tumors of the nervous system. Major changes include the addition of new entities and the refinement of criteria for the diagnosis and grading of various neoplasms, in particular the meningiomas. As novel clinico-pathological entities, the chordoid glioma of the third ventricle, the atypical teratoid/rhabdoid tumor (AT/RT), the solitary fibrous tumor, and the perineurioma have been listed. The former lipomatous medulloblastoma of the cerebellum, previously incorporated in the family of embryonal tumors, is now classified as cerebellar liponeurocytoma. The term mixed pineocytoma/pineoblastoma has been replaced by pineal parenchymal tumor of intermediate differentiation. Furthermore, the large cell medulloblastoma and the tanycytic ependymoma were established as novel tumor variants. A separate chapter on the peripheral neuroblastic tumors has now been included in the classification. Substantial revisions were introduced in the meningioma chapter. For both atypical meningioma WHO grade II and anaplastic meningioma WHO grade III, histopathological criteria are now precisely defined. An important new addition to the WHO 2000 classification of nervous system tumors is the inclusion of molecular pathology findings. With this combination of pathology and genetics it has set the stage for a new format of the WHO tumor classification series.
Extracellular matrix-degrading enzymes are crucial for cancer metastases. One group of enzymes that has been increasingly implicated in the breakdown of the extracellular matrix, and hence the intravasation and dissemination of tumour cells, is the family of metalloproteinases. In the recent past, increasing efforts have led to the development of more or less specific matrix metalloproteinase (MMP) inhibitors. Data concerning the molecular nature and timing of the contribution of MMPs to tumour spread is of paramount importance in clarifying which MMP is an appropriate target for more selective MMP inhibition in future tumour therapy. This study immunohistochemically characterized the expression pattern of MMP-2, -3, and -9 in 26 uveal melanomas. Forty-six per cent of the uveal melanomas expressed MMP-2 and/or MMP-9. MMP-3 expression was seen in 17 out of 26 uveal melanomas. MMP-9, previously shown to play an important part in tumour dissemination, was predominantly present in epithelioid melanomas (71.4%) or the epithelioid portion of mixed cell uveal melanomas (67%), whereas only one out of ten spindle cell melanomas showed MMP-9 expression (10%). MMP-2 and MMP-9 expression was associated with a significantly higher incidence of metastatic disease. The survival rate of patients with MMP-2-positive melanomas was 31% vs. 85% for patients with MMP-2-negative (p<0.05); for MMP-9-positive uveal melanomas the survival rate was 27% vs. 85% with MMP-9-negative uveal melanomas (p<0.04). The fact that patients suffering from TIMP-1- as well as TIMP-2-positive uveal melanomas tended to show a better survival rate (72% vs. 45% for TIMP-1; 88% vs. 37% for TIMP-2) supports the view that proteolytic enzymes are of importance in tumour spread.
As an anatomical interface between various tissues, the skull base harbors an exceptionally broad variety of neoplasms, some of which pose a major challenge for surgical pathology. The characterization of distinct immunohistochemical expression profiles and the identification of molecular genetic alterations associated with different tumor entities have significantly advanced this field. The new World Health Organization (WHO) classification of tumors of the nervous system lists 15 histopathological variants of meningioma. Of clinical importance are those entities that carry an increased risk of recurrence and a poor prognosis, i.e., the atypical meningioma (WHO grade II), clear-cell meningioma (WHO grade II), chordoid meningioma (WHO grade II), rhabdoid meningioma (WHO grade III), papillary meningioma (WHO grade III), and anaplastic meningioma (WHO grade III). Diagnostic criteria for atypical and anaplastic meningioma variants have now been stringently defined. The differential diagnosis of meningiomas includes hemangiopericytoma, hemangioblastoma, solitary fibrous tumor, sarcomas, and chordoid neoplasms. Recent data highlight the importance of distinguishing chordoma and chondrosarcoma of the skull base since chondrosarcomas show a significantly better clinical outcome. Among the less common, aggressive tumor entities in this anatomical region, infiltrating pituitary adenoma/pituitary carcinoma, superficial malignant gliomas, rhabdomyosarcoma, olfactory neuroblastoma, various sarcomas, and malignant lymphoma must be considered. Profiles of molecular genetic alterations have been established for several of these neoplasms and may facilitate the differential diagnosis. This review summarizes recent developments in the histopathological characterization, classification, and molecular pathology of neoplasms arising at the skull base.
Lipoprotein lipase (LpL) binding to heparan sulfate proteoglycans (HSPGs) is hypothesized to stabilize the enzyme, localize LpL in specific capillary beds, and route lipoprotein lipids to the underlying tissues. To test these hypotheses in vivo, we created mice expressing a human LpL minigene (hLpL(HBM)) carrying a mutated heparin-binding site. Three basic amino acids in the carboxyl terminal region of LpL were mutated, yielding an active enzyme with reduced heparin binding. Mice expressing hLpL(HBM) accumulated inactive human LpL (hLpL) protein in preheparin blood. hLpL(HBM) rapidly lost activity during a 37 degrees C incubation, confirming a requirement for heparin binding to stabilize LPL: Nevertheless, expression of hLpL(HBM) prevented the neonatal demise of LpL knockout mice. On the LpL-deficient background hLpL(HBM) expression led to defective targeting of lipids to tissues. Compared with mice expressing native hLpL in the muscle, hLpL(HBM) transgenic mice had increased postprandial FFAs, decreased lipid uptake in muscle tissue, and increased lipid uptake in kidneys. Thus, heparin association is required for LpL stability and normal physiologic functions. These experiments confirm in vivo that association with HSPGs can provide a means to maintain proteins in their stable conformations and to anchor them at sites where their activity is required.
Although intoxications with colchicine, the alkaloid of Colchicum autumnale (meadow saffron), are well known, in most cases the intoxications are evoked by oral or parenteral preparations traditionally used as medication against gout. The accidental ingestion of Colchicum autumnale, on the other hand, is a rare event and has to our knowledge only twice been described in detail. We report a further case in which two persons confused this highly poisonous plant with wild garlic (Allium ursinum), a popular spice in the Central European cuisine. While one person merely complained about a 3-day episode of nausea, vomiting and watery diarrhea, the second person died of multi-organ system derangements 48 h after the ingestion of the colchicum leaves. At autopsy hemorrhagic lung oedema, hypocellular bonemarrow, centrilobular fatty necrosis of the liver and necrosis of the proximal convoluted tubuli of the kidneys were observed. A colchicine concentration of 7.5 micrograms/ml was found in the bile whereas no substance was detected in the postmortem blood.
The tissue-specific expression of lipoprotein lipase (LPL) in adipose tissue (AT), skeletal muscle (SM), and cardiac muscle (CM) is rate-limiting for the uptake of triglyceride (TG)-derived free fatty acids and decisive in the regulation of energy balance and lipoprotein metabolism. To investigate the tissue-specific metabolic effects of LPL, three independent transgenic mouse lines were established that expressed a human LPL (hLPL) minigene predominantly in CM. Through cross-breeding with heterozygous LPL knockout mice, animals were generated that produced hLPL mRNA and enzyme activity in CM but lacked the enzyme in SM and AT because of the absence of the endogenous mouse LPL gene (L0-hLPL). LPL activity in CM and postheparin plasma of L0-hLPL mice was reduced by 34% and 60%, respectively, compared with control mice. This reduced LPL expression was sufficient to rescue LPL knockout mice from neonatal death. L0-hLPL animals developed normally with regard to body weight and body-mass composition. Plasma TG levels in L0-hLPL animals were increased up to 10-fold during the suckling period but normalized after weaning and decreased in adult animals. L0-hLPL mice had normal plasma high-density lipoprotein (HDL)-cholesterol levels, indicating that LPL expression in CM alone was sufficient to allow for normal HDL production. The absence of LPL in SM and AT did not cause detectable morphological or histopathological changes in these tissues. However, the lipid composition in AT and SM exhibited a marked decrease in polyunsaturated fatty acids. From this genetic model of LPL deficiency in SM and AT, it can be concluded that CM-specific LPL expression is a major determinant in the regulation of plasma TG and HDL-cholesterol levels.
Myogelosis is a common diagnosis in the case of chronic pain conditions, especially in the region of the pectoral girdle musculature, the glutei muscles, and the erector spinae muscle. Although such indurative areas continue to be palpable even on the cadaver, few studies concerning the morphological substrate of these areas have been undertaken. Selected biopsies as well as larger tissue samples were taken from 11 corpses and prepared for histological study. Following staining, the frozen sections were examined morphometrically. A histologically constant, significant morphological alteration was found in the areas of concern. The spaces between the individual muscle fibers of healthy muscle tissue appear relatively wide, the endomysium of the myogelotic area are clearly narrowed. Split fibers, ragged red fibers, Type II fiber atrophy, and fibers with a moth-eaten appearance have been detected. The morphometry shows considerable increase in thickness of the affected muscle fibers, suggestive of a pathological, local hypertrophy. The changes described may well represent a fixed condition, so that it should not be surprising that myogelosis therapy is difficult and protracted.
Metastasising chordomas are extremely rare and only four cases with drop metastases have been reported. We report a patient with an intracranial chondroid chordoma, typically involving the clivus, treated by repeated resection, percutaneous transluminal embolisation and radiosurgery. During follow-up with MRI asymptomatic intradural drop metastases were observed throughout the spine, with transgression of the intervertebral foramen, forming a "dumbbell".
Hereditary spastic paraplegia is a group of clinically and genetically heterogeneous disorders consisting of pure and complicated forms. A variant with the additional features of severe atrophy of the small hand muscles, dysarthria, mental retardation, and short stature has been termed Troyer syndrome (MIM#275900) after the name of Old Order Amish families suffering from these symptoms. We report here an Austrian family with two individuals who exhibit all the features of Troyer syndrome, and provide additional data on this disorder. Electrophysiological studies showed chronic denervation and reduced motor nerve conduction velocities but normal sensory potentials. Muscle biopsy revealed a neurogenic pattern while the sural nerve was normal on histological examination. Brain abnormalities on magnetic resonance imaging consisted of a thin corpus callosum with a poorly developed cingulate gyrus and mild periventricular signal hyperintensities. These findings characterize the Troyer syndrome as a disorder of the first and second motor neuron with additional damage in the brain. The morphological features observed in this family may contribute to the grouping and subsequent understanding of complicated forms of hereditary spastic paraplegia, together with similar observations in other, more recently reported families.
PURPOSE: To investigate the possible role of UV-radiation in the development of conjunctival malignant melanoma. N-ras mutations are frequently found in cutaneous melanomas of sun-exposed body areas. UV-radiation is thought to induce mutations in the N-ras gene, that convert these genes into active oncogenes. The presence of N-ras mutations has been considered an indicator for UV-exposure in the development of melanomas on sun-exposed body sides. METHODS: We analyzed six paraffin-embedded conjunctival melanomas for mutations of the N-ras gene. Codons 12, 13 and 61 were amplified using polymerase chain reaction and sequenced. RESULTS: We could not detect point mutations of the N-ras gene in our samples. CONCLUSION: Since we could not find deviations from the wild type sequence in the N-ras gene, our study does not support UV-exposure as being causative in the development of conjunctival melanoma.
After twenty-five years of therapy with different unifocal pacemaking systems, an 84-year old male patient developed a nonseptic pacemaker decubitus. A rare incidental finding of invasive ductal carcinoma of the right mammary gland was surgically treated by a generous excision of the tumor and by consecutive modified radical mastectomy. According to published literature, the association of invasive ductal carcinoma arising from a pacemaker pocket decubitus and followed by curative treatment has not been previously reported. We do conclude that pacemaker generators in close relationship to the mammary gland should be considered with suspicion.
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Lipoprotein lipase (LPL) is the central enzyme in plasma triglyceride hydrolysis. In vitro studies have shown that LPL also can enhance lipoprotein uptake into cells via pathways that are independent of catalytic activity but require LPL as a molecular bridge between lipoproteins and proteoglycans or receptors. To investigate whether this bridging function occurs in vivo, two transgenic mouse lines were established expressing a muscle creatine kinase promoter-driven human LPL (hLPL) minigene mutated in the catalytic triad (Asp156 to Asn). Mutated hLPL was expressed only in muscle and led to 3,100 and 3,500 ng/ml homodimeric hLPL protein in post-heparin plasma but no hLPL catalytic activity. Less than 5 ng/ml hLPL was found in preheparin plasma, indicating that proteoglycan binding of mutated LPL was not impaired. Expression of inactive LPL did not rescue LPL knock-out mice from neonatal death. On the wild-type (LPL2) background, inactive LPL decreased very low density lipoprotein (VLDL)-triglycerides. On the heterozygote LPL knock-out background (LPL1) background, plasma triglyceride levels were lowered 22 and 33% in the two transgenic lines. After injection of radiolabeled VLDL, increased muscle uptake was observed for triglyceride-derived fatty acids (LPL2, 1.7x; LPL1, 1.8x), core cholesteryl ether (LPL2, 2.3x; LPL1, 2.7x), and apolipoprotein (LPL1, 1.8x; significantly less than cholesteryl ether). Skeletal muscle from transgenic lines had a mitochondriopathy with glycogen accumulation similar to mice expressing active hLPL in muscle. In conclusion, it appears that inactive LPL can act in vivo to mediate VLDL removal from plasma and uptake into tissues in which it is expressed.
Boron neutron capture therapy (BNCT) represents a highly promising therapeutic alternative for the treatment of the most common malignant brain tumor, glioblastoma multiforme. Both the efficacy and safety of BNCT are greatly dependent on the pattern of 10B biodistribution. The present study investigates the influence of systemic hyaluronidase applied in combination with Na2B12H11SH (BSH), a boron carrier used in current clinical trials. The application of hyaluronidase was associated with a statistically significant improvement in the tumor/blood boron concentration ratio which suggests that hyaluronidase is capable of enhancing the therapeutic potential of BSH.
Lipoprotein lipase (LPL), the rate-limiting enzyme in triglyceride hydrolysis, is normally not expressed in the liver of adult humans and animals. However, liver LPL is found in the perinatal period, and in adults it can be induced by cytokines. To study the metabolic consequences of liver LPL expression, transgenic mice producing human LPL specifically in the liver were generated and crossed onto the LPL knockout (LPL0) background. LPL expression exclusively in liver rescued LPL0 mice from neonatal death. The mice developed a severe cachexia during high fat suckling, but caught up in weight after switching to a chow diet. At 18 h of age, compared with LPL0 mice, liver-only LPL-expressing mice had equally elevated triglycerides (10,700 vs. 14,800 mg/dl, P = NS), increased plasma ketones (4.3 vs. 1.7 mg/dl, P < 0.05) and glucose (28 vs. 15 mg/dl, P < 0.05), and excessive amounts of intracellular liver lipid droplets. Adult mice expressing LPL exclusively in liver had slower VLDL turnover than wild-type mice, but greater VLDL mass clearance, increased VLDL triglyceride production, and three- to fourfold more plasma ketones. In summary, it appears that liver LPL shunts circulating triglycerides to the liver, which results in a futile cycle of enhanced VLDL production and increased ketone production, and subsequently spares glucose. This may be important to sustain brain and muscle function at times of metabolic stress with limited glucose availability.