PubMed Health⌕ Search

Biomedical subjects

A Nerlich

Publications and source records attributed to A Nerlich.

At least 19 recordsLinked to original sources
PubMed2001

Impaired tensile strength after shock-wave application in an animal model of tendon calcification.

Extracorporeal shock-wave application facilitates dissolution of rotator cuff calcifications. Therefore, disappearance or disintegration of tendon calcifications by shock waves might be appropriate for any kind of tendon calcification. Here, shock waves with various energy flux densities were applied to the mineralized medial gastrocnemius tendon of turkeys as an animal model. After application of shock waves in vivo, with energy flux density of 0.6 mJ/mm(2), histologic examination and microradiography did not show dissolution or disintegration of tendon calcifications. After shock-wave application in vitro, even for energy flux density of 1.2 mJ/mm(2) neither dissolution nor disintegration of tendon calcifications were observed. Biomechanical testing revealed significant impairment of tensile strength following shock-wave application in vitro, with energy flux density of 1.2 mJ/mm(2), but not with 0.6 mJ/mm(2). These results are important for considerations of clinical extracorporeal shock-wave application on tendon calcifications, as well as on tendon ossifications.

Animals↗
PubMed2000

Chondromyxoid fibroma of bone.

Chondromyxoid fibroma is a benign, although potentially aggressive tumor, with a cartilage-like matrix, accounting for approximately 1% of all bone tumors. It usually affects the metaphyseal region of long bones of patients in their first or second decade of life. An additional peak of incidence has been observed between 50 and 70 years of age. Three cases are presented here: 10-, 13-, and 52-year-old patients, with lesions in the proximal tibia, the proximal humerus, and the proximal femur, respectively. The literature is reviewed in terms of clinical behavior, diagnostic procedures, prognostic factors, treatment, and outcome. Preferred treatment is complete local excision with tumor-free margins. Intralesional curettage with or without local adjuvants shows a local recurrence rate of approximately 25%. Radiation therapy may be useful in nonresectable cases but bears the well documented risk of radiation-induced malignancies.

Adolescent↗
PubMed2000

Malignant hemangiopericytoma of the bone.

Hemangiopericytoma is a rare vascular tumor of pericyte origin with variable malignant potential. Very rarely, this tumor occurs as a primary bone lesion. We present a case of a highly malignant hemangiopericytoma of the proximal tibia. Current therapy consists of radical resection of the tumor with postoperative radiation therapy being recommended. Chemotherapy seems to be useful in disseminated disease. The prognosis correlates to the histological grading of the tumor. Early or late recurrence and distant metastases with fatal outcome, as shown in our case study, are not uncommon.

Amputation, Surgical↗
PubMed2000

[The interesting case No. 39. Differential diagnosis of acute antibiotic-resistant pharyngitis].

We report on a 41-year old female patient presenting a history of long-term sore throat, in addition to ulcers on both tonsils, the base of the tongue, the hypopharyngeal mucosa, and a laryngeal edema. She underwent diagnostic tonsillectomy and microlaryngoscopy on the suspicion of malignancy. Clinical and histopathological investigations demonstrated granulomatous inflammation with necrosis containing acid-fast rods in the tissue specimens. Furthermore, the presence of acid-fast bacilli in the bronchial lavage suggested the diagnosis of a possibly reactivated pulmonary tuberculosis. The present case provides evidence that pharyngeal tuberculosis may represent the first manifestation of tuberculosis. Therefore, the differential diagnosis of nonspecific symptoms such as sore throat should include tuberculosis as a causative factor.

Acute Disease↗
PubMed2000

The molybdenum cofactor biosynthetic protein Cnx1 complements molybdate-repairable mutants, transfers molybdenum to the metal binding pterin, and is associated with the cytoskeleton.

Molybdenum (Mo) plays an essential role in the active site of all eukaryotic Mo-containing enzymes. In plants, Mo enzymes are important for nitrate assimilation, phytohormone synthesis, and purine catabolism. Mo is bound to a unique metal binding pterin (molybdopterin [MPT]), thereby forming the active Mo cofactor (Moco), which is highly conserved in eukaryotes, eubacteria, and archaebacteria. Here, we describe the function of the two-domain protein Cnx1 from Arabidopsis in the final step of Moco biosynthesis. Cnx1 is constitutively expressed in all organs and in plants grown on different nitrogen sources. Mo-repairable cnxA mutants from Nicotiana plumbaginifolia accumulate MPT and show altered Cnx1 expression. Transformation of cnxA mutants and the corresponding Arabidopsis chl-6 mutant with cnx1 cDNA resulted in functional reconstitution of their Moco deficiency. We also identified a point mutation in the Cnx1 E domain of Arabidopsis chl-6 that causes the molybdate-repairable phenotype. Recombinant Cnx1 protein is capable of synthesizing Moco. The G domain binds and activates MPT, whereas the E domain is essential for activating Mo. In addition, Cnx1 binds to the cytoskeleton in the same way that its mammalian homolog gephyrin does in neuronal cells, which suggests a hypothetical model for anchoring the Moco-synthetic machinery by Cnx1 in plant cells.

Amino Acid Sequence↗
PubMed2000

Anthropological and palaeopathological analysis of the human remains from three "Tombs of the Nobles" of the necropolis of Thebes-west, upper Egypt.

During several recent excavation campaigns at the necropolis of Sheikh-Abd-el-Gurna, Thebes-West, Upper Egypt, we investigated the human remains of three "Tombs of the Nobles" totalling at least 273 individuals. The investigation covered the human material (skeletons and mummy residues) from the tombs TT-84, TT-85 and TT-95. These tombs had been built in the New Kingdom (approx. 1500-1000 B.C.) and used until the Late period (up to 330 BC). All samples were analyzed macroscopically, isolated findings were further investigated by endoscopic and radiological techniques. The at least 273 individuals covered an age range from newborns to senile individuals with a main age of death between 20 and 40 years of age. The rate of infants and subadults was at 20.2% of all individuals and there was a slight male predominance comprising 54.5% of the adults. In this population a fairly high rate of pathological lesions was seen. Thus, dental conditions generally were poor with a high degree of dental abrasion, an also high rate of carious dental lesions (affecting between 13.8% and 27.7% of the yaws) and consequently a significant number of dental abscesses (mean 15.9%). Residues of trauma were observed in a considerable number of individuals ranging between 12.3% and 22.6% depending on the burial place (mean 15.8%). Inflammatory bone reactions (except the dental abscesses) were present to variable extent, in some locations ranging up to 6.8% of the cases (mean 5.1%). In addition, we noted several cases showing cribra orbitalia (mean 29.2%) and porotic hyperostosis (15.4% of cases), mild to severe osteopenia (7.5%) and in several cases subperiosteal new bone formation suggestive of chronic vitamin D-deficiency ("scurvy") (9.5%). The data support the notion of a significant impairment of living conditions in a high number of individuals. The rates of osteoarthrotic joint alterations were considerably variable depending on the burial places (between 1.9% and 18.5%) providing insight into the physical activities of subpopulations in different locations of the burial places. Similarly, the rate of spondylosis showed also variable extent ranging between 12% and 66.1% of vertebral bodies. In general, our analysis provides evidences that the living conditions in the ancient Egyptian population of one of the main necropoles of Thebes analyzed in this study were quite poor. This is somewhat in contrast to the usually assumed high standard of living of the socially higher population of the capital of ancient Egypt.

Adolescent↗
PubMed1999

The neurotransmitter receptor-anchoring protein gephyrin reconstitutes molybdenum cofactor biosynthesis in bacteria, plants, and mammalian cells.

The molybdenum cofactor (Moco), a highly conserved pterin compound complexing molybdenum, is required for the enzymatic activities of all molybdenum enzymes except nitrogenase. Moco is synthesized by a unique and evolutionarily old pathway that requires the activities of at least six gene products. Some of the proteins involved in bacterial, plant, and invertebrate Moco biosynthesis show striking homologies to the primary structure of gephyrin, a polypeptide required for the clustering of inhibitory glycine receptors in postsynaptic membranes in the rat central nervous system. Here, we show that gephyrin binds with high affinity to molybdopterin, the metabolic precursor of Moco. Furthermore, gephyrin expression can reconstitute Moco biosynthesis in Moco-deficient bacteria, a molybdenum-dependent mouse cell line, and a Moco-deficient plant mutant. Conversely, inhibition of gephyrin expression by antisense RNA expression in cultured murine cells reduces their Moco content significantly. These data indicate that in addition to clustering glycine receptors, gephyrin also is involved in Moco biosynthesis and illustrate the remarkable conservation of its function in Moco biosynthesis throughout phylogeny.

Animals↗
PubMed1999

[Rapidly progressing course of cutaneous angiosarcoma in the area of the head-neck].

INTRODUCTION: Angiosarcomas are rare, aggressive tumors of vascular origin, most commonly affecting older males. An optimum treatment strategy has not yet been defined. CASE REPORT: We report on a 68-year-old male patient who initially presented with a small, bruise-like macule of the cheek. He was treated with different antibiotics and steroids for a few weeks. Due to failure of any clinical improvement, a biopsy was taken revealing an undifferentiated malignant tumor. Subsequently, the patient was referred to our department, where the lesion was excised. Histology showed an extensive, well-differentiated angiosarcoma. According to oncological protocols, the patient underwent 5 cycles of chemotherapy with etoposid, ifosphamid and adriamycine. Despite therapy, tumor size remained unchanged. After therapy was discontinued, tumor growth rapidly proceeded with semicircular infiltration of the right face and neck. A few weeks later the patient died. DISCUSSION: About 50 percent of cutaneous angiosarcomas are found in the head and neck region of the elderly. No clear etiology has been implicated with respect to the origin of this tumor. Traumatic bruises, infections, and allergic reaction may be confused clinically with angiosarcoma. Differential diagnosis also comprises other vascular neoplastic diseases, i.e. lymphangioma, hemangiopericytoma and Kaposi's sarcoma. If complete excision is possible, radical surgery is the treatment of choice. The effectiveness of chemotherapy is unclear. The role of radiation therapy is also under discussion due to the technical problems of administering radiotherapy to the extensive volume at risk. As the late diagnosis adversely affects the prognosis, the importance of early biopsy in suspicious lesions is mandatory.

Aged↗
PubMed1999

Use of three-phase bone scans and SPET in the follow-up of patients with allogenic vascularized femur transplants.

The vascularized allotransplantation of femoral diaphyses under immunosuppression is a novel approach in orthopaedic surgery. To evaluate which method provides the best information about microvascularity and viability of the transplant, we compared different diagnostic approaches used in transplant surgery. Three patients were investigated four times over a period of 1 month (on days 2, 7, 15 and 30 post-transplantation) and 6 and 12 months later with planar 99Tcm-MDP three-phase bone scintigraphy and SPET. The results were compared with duplex sonography, angiography and intraoperative biopsies. Rejection and thrombosis of the transplant were associated with decreased or missing perfusion detected by duplex sonography, angiography and blood pool scintigraphy. In these cases, late bone scans showed reduced or absent bone metabolism while biopsy revealed necrotic bone tissue. In cases without complications, blood pool scans revealed hyperaemia of the graft indicating excellent perfusion and patency of vascular anastomoses and transplant vessels. Late bone scans demonstrated increased bone metabolism. The corresponding biopsies showed viable bone cells. We conclude that bone scintigraphy is a valuable diagnostic tool in vascularized femur allotransplantation, since it provides reliable information on both viability and perfusion of the transplant within a single non-invasive investigation.

Adult↗
PubMed1998

High glucose-induced transforming growth factor beta1 production is mediated by the hexosamine pathway in porcine glomerular mesangial cells.

Previous studies revealed that exposure of mesangial cells to high glucose concentration induces the production of matrix proteins mediated by TGF-beta1. We tested if structural analogues of D-glucose may mimic the high glucose effect and found that D-glucosamine was strikingly more potent than D-glucose itself in enhancing the production of TGF-beta protein and subsequent production of the matrix components heparan sulfate proteoglycan and fibronectin in a time- and dose-dependent manner. D-Glucosamine also promoted conversion of latent TGF-beta to the active form. Therefore, we suggested that the hexosamine biosynthetic pathway (the key enzyme of which is glutamine:fructose-6-phosphate amidotransferase [GFAT]) contributes to the high glucose-induced TGF-beta1 production. Inhibition of GFAT by the substrate analogue azaserine or by inhibition of GFAT protein synthesis with antisense oligonucleotide prevented the high glucose-induced increase in cellular glucosamine metabolites and TGF-beta1 expression and bioactivity and subsequent effects on mesangial cell proliferation and matrix production. Overall, our study indicates that the flux of glucose metabolism through the GFAT catalyzed hexosamine biosynthetic pathway is involved in the glucose-induced mesangial production of TGF-beta leading to increased matrix production.

Animals↗
PubMed1998

Allogenic grafting of vascularized bone segments under immunosuppression. Clinical results in the transplantation of femoral diaphyses.

Trauma surgery lack, substitute, for the reconstruction of large defects of the long bones. Encouraged by the promising results of bone allotransplantation in animal models, we successfully performed vascularized bone transplantation in humans. Vascularized femoral diaphyses were allogenically transplanted into three patients suffering from chondrosarcoma or post-traumatic osteomyelitis with postoperative immunosuppression. The bone segments were harvested from multi-organ donors and perfused with UW solution. After back-table preparation, the grafts were transplanted into the defect zone. Interlocking devices were used in these operations. Vascular anastomoses were performed in end-to-side technique. The early clinical course of the patients was not free of anatomical, technical, or immunological complications. However, all patients are currently free of malignancy and infection. They are also free of pain and full weight bearing. We conclude that allogenic grafting of vascularized bone segments has the potential to become an alternative for the replacement of large bone defects.

Adult↗
PubMed1998

[Fibrillary glomerulonephritis. Case report for differential nephrotic syndrome diagnosis].

A 67-year-old male patient presented with a nephrotic syndrome. Biopsy of the kidney revealed the characteristic of fibrillary glomerulopathy on light and electron microscopy. Other non-nephritic causes of a nephrotic syndrome (e.g. amyloidosis, immunotactoid glomerulopathy, light-chain glomerulopathy, cryoglobulinaemia, collagen-III glomerulopathy, fibronectin glomerulopathy) could be excluded. Besides the case report, differential diagnosis of fibrillary glomerulopathies is presented.

Actin Cytoskeleton↗
PubMed1998

The time-related expression of p53 protein in human skin wounds--a quantitative immunohistochemical analysis.

The time-dependent expression of p53 protein during wound healing has been investigated by immunochemistry in fibroblastic cells of skin wounds ranging between a few minutes and 11 weeks old. When compared to uninjured skin, an increased expression of p53 was found earliest in a wound with a postinfliction interval of 3 days. The ratio (r) of positively stained cells in relation to the total number of fibroblastic cells in the wound area of this specimen was about 0.2. A considerable increase in the expression of p53 (r > 0.5) was first found in a wound aged 8 days and in wounds with postinfliction intervals ranging between 3 and 11 weeks, where the ratio of positive cells was between 0.40 and 0.64. Therefore, it can be calculated that r-values of at least 0.5 indicate a postinfliction interval of approximately 1 week or more. Since comparably low numbers of positively stained fibroblastic cells were found in specimens with an advanced wound duration, reliable information for a forensic wound age estimation can only be provided by positive results.

Adolescent↗
PubMed1998

Embryonal rhabdomyosarcoma of the nose in an elderly patient, case report and review of the literature.

Embryonal rhabdomyosarcoma of the head and neck is very rare in adults. We report on an embryonal rhabdomyosarcoma of the nose, occuring in a 74-year-old female patient presenting with nasal congestion as the only clinical symptom. Suspected to be an amelanotic melanoma, further biopsies and histological examinations provided the correct diagnosis. She first underwent a course of chemotherapy which led to a partial shrinkage of the tumor mass which was followed by a complete resection of the residual tumor mass. Biologic behaviour of this tumor must be fully appreciated as treatment is interdisciplinary. Rhabdomyosarcoma should be considered in the differential diagnosis of tumors of the nose and paranasal sinuses not only in children, but also in adults.

Age Distribution↗
PubMed1998

[Intra-parotid neurofibroma of the facial nerve].

BACKGROUND: Solitary intraparotid facial neurofibromas are extremely rare. These tumours arise from Schwann cells, in most cases as a manifestation of neurofibromatosis. In an intraparotid localisation, they can mimic other parotideal tumours. Due to their slow growth, they may be clinically inapparent for a long time. CASE REPORT: We present the case of a patient with a right intraparotid neurofibroma originating from the facial nerve. He noted a slight facial weakness for the last three years and dullness over the preauricular area. On operation, all facial nerve branches were incorporated in the tumour mass. A total resection via monitoring technique of facial nerve function was performed. Postoperatively, the patient suffered from an incomplete facial palsy. CONCLUSION: This case highlights particularly the importance of a concise diagnostic work-up of every facial palsy. Precise histological diagnosis is particularly essential because of the different biological behaviour of neurofibromas in contrast to neurinomas. With preoperative facial palsy the chance of facial nerve preservation decreases. Clinical and operative experience with parotid gland neurofibromas shows that recovery of facial nerve defects is mostly incomplete.

Cranial Nerve Neoplasms↗
PubMed1997

The arterial blood supply of the human patella. Its clinical importance for the operating technique in vascularized knee joint transplantations.

The architecture of the arteries supplying the patellar rete was examined in 14 anatomic specimens in order to develop an optimized operating technique for knee joint transplantation. The specimens were fixed in Jores Solution and exarticulated from the hip joint. The lower limbs were injected with Berliner-Blau-Gelatin, and the arteries were dissected macroscopically. Five to six main arteries entered the patellar rete at 1, 3, 5, 7 and 11 o'clock forming an arterial circle. These arteries were the same main arteries which supply the distal end of the femur and the proximal part of the tibia. From an anatomic perspective, they provide the complete arterial blood supply to a whole knee joint being transplanted including the patella. Based on these anatomic results, we transplanted two allogenic vascularized human knee joints preserving the patella, the capsule, and the patellar ligament. Up to six months after surgery we demonstrated the perfusion and viability of all three transplanted bones, particularly the patella, by 99mTc DPD scintigraphy. We compared these findings with knee joint arthroscopy and with histologic results from biopsies taken from the patella. The postoperative examinations clearly indicated the viability of the transplanted patella employing this new operating technique. The results of the entire study demonstrate that it is technically feasible to transplant a whole knee joint which remains clinically viable.

Adult↗