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J Müller-Höcker

Publications and source records attributed to J Müller-Höcker.

At least 19 recordsLinked to original sources
PubMed2006

Benign symmetric lipomatosis with axonal neuropathy and abnormalities in specific mitochondrial tRNA regions.

Benign symmetric lipomatosis, also called Madelung's disease, is characterized by lipomata and fatty infiltrations. Involvement of the nervous system has occasionally been described, mitochondrial dysfunctions have been suggested. We report a 55 year old male suffering from benign symmetric lipomatosis with associated axonal neuropathy and hyperlipoproteinemia. He showed a remarkable phenotype of neuropathy i.e. no sensory disturbance, ubiquitous fasciculations and muscle cramps, furthermore reduced COX activity and abnormalities in specific mitochondrial tRNA regions.

Axons↗
PubMed2006

Aggressive scapular chondroblastoma with secondary metastasis--a case report and review of literature.

Chondroblastoma is a benign bone tumor, accounting for approximately one percent of all benign bone tumors. It mostly occurs in typical locations such as long bones. Malignant transformation including metastasis has been described in only a few cases. Therefore, we report a unique case of chondroblastoma with tumor manifestation in the 7th decade of life, location of the tumor in the scapula and occurrence of metastasis in the soft tissue of the mandible branch. Due to aggravation of the clinical course, a scapula en bloc resection was performed. The differential diagnosis is discussed and the current literature concerning malignant transformation of chondroblastoma is reviewed.

Aged↗
PubMed2006

Coenzyme Q10 deficiency and isolated myopathy.

Three unrelated, sporadic patients with muscle coenzyme Q10 (CoQ10) deficiency presented at 32, 29, and 6 years of age with proximal muscle weakness and elevated serum creatine kinase (CK) and lactate levels, but without myoglobinuria, ataxia, or seizures. Muscle biopsy showed lipid storage myopathy, combined deficiency of respiratory chain complexes I and III, and CoQ10 levels below 50% of normal. Oral high-dose CoQ10 supplementation improved muscle strength dramatically and normalized serum CK.

Adult↗
PubMed2005

Mutations in mtDNA-encoded cytochrome c oxidase subunit genes causing isolated myopathy or severe encephalomyopathy.

We report on clinical, histological and genetic findings in two patients carrying novel heteroplasmic mutations in the mitochondrial cytochrome c oxidase subunit genes COII and COIII. The first patient, a 35 year-old man had a multisystemic disease, with clinical symptoms of bilateral cataract, sensori-neural hearing loss, myopathy, ataxia, cardiac arrhythmia, depression and short stature and carried a 7970 G>T (E129X) nonsense mutation in COII. A sudden episode of metabolic encephalopathy caused by extremely high blood lactate lead to coma. The second patient developed exercise intolerance and rhabdomyolysis at age 22 years. A heteroplasmic missense mutation 9789 T>C (S195P) was found in skeletal muscle, but not in blood and myoblasts pointing to a sporadic mutation. Our report of two patients with isolated COX deficiency and new mutations in COX subunit genes may help to draw more attention to this type of mtDNA defects and provide new aspects for counselling affected families.

Adult↗
PubMed2005

[Schistosomiasis in a leiomyoma of the uterus].

This case report deals with an, in our regions, unusual diagnosis of coincidence of a genital schistosomiasis of a 30-year-old woman, coming from Africa. The female patient presented herself by a specialist because of longer lasting hypermenorrhoe. After clinical examination the patient underwent an operation because of an uterus myomatosus. The histopathological evaluation showed beside a leimyoma an expanded infestation with schistosomiasis haematobium. After pathological diagnosis the patient underwent the standard therapy with a single injection of praziquantel. We report about the clinic, epidemiology, morphology and diagnostic.

Adult↗
PubMed2005

Congenital cataract, muscular hypotonia, developmental delay and sensorineural hearing loss associated with a defect in copper metabolism.

Deficiencies of different proteins involved in copper metabolism have been reported to cause human diseases. Well-known syndromes, for example, are Menkes and Wilson diseases. Here we report a patient presenting with congenital cataract, severe muscular hypotonia, developmental delay, sensorineural hearing loss and cytochrome-c oxidase deficiency with repeatedly low copper and ceruloplasmin levels. These findings were suggestive of a copper metabolism disorder. In support of this, the patient's fibroblasts showed an increased copper uptake with normal retention. Detailed follow-up examinations were performed. Immunoblotting for several proteins including ATP7A (MNK or Menkes protein), ATP7B (Wilson protein) and SOD1 showed normal results, implying a copper metabolism defect other than Wilson or Menkes disease. Sequence analysis of ATOX1 and genes coding for proteins that are known to play a role in the mitochondrial copper metabolism (COI-III, SCO1, SCO2, COX11, COX17, COX19) revealed no mutations. Additional disease genes that have been associated with cytochrome-c oxidase deficiency were negative for mutations as well. As beneficial effects of copper histidinate supplementation have been reported in selected disorders of copper metabolism presenting with low serum copper and ceruloplasmin levels, we initiated a copper histidinate supplementation. Remarkable improvement of clinical symptoms was observed, with complete restoration of cytochrome-c oxidase activity in skeletal muscle.

Adenosine Triphosphatases↗
PubMed2003

Chief cell proliferation of the gastric mucosa mimicking early gastric cancer: an unusual variant of fundic gland polyp.

We describe a hitherto unknown lesion of gastric chief cell proliferation mimicking structurally mucosal gastric cancer. The unremarkable cytology of the cells, their very low Ki-67 index, the inclusion of occasional parietal cells and especially ultrastructural evidence of chief cell differentiation proved helpful in the differentiation from early gastric cancer. The exact classification of the alteration remains unresolved. The presence of microcysts suggests that the lesion is a variant of fundic gland polyp formation.

Aged↗
PubMed2003

Chloroquine-induced phospholipidosis of the kidney mimicking Fabry's disease: case report and review of the literature.

A 46-year-old female patient with Sjögren's syndrome, hypertension, and stable chronic renal insufficiency (creatinine [CR], 1.9 to 2.1 mg/dL) had a progressive worsening of renal function (CR, 5.0 mg/dL) after 11 months of chloroquine therapy (155 mg/day; cumulative dose of approximately 51 g). Light microscopy revealed nonspecific angionephrosclerosis. Electron microscopy showed accumulations of lamellated myelinoid material and occasionally also of curvilinear bodies, especially in the glomerular podocytes and to a lesser extent in vascular myothelial and endothelial cells. In the tubular system, mainly protein droplets were stored. Activity of alpha-galactosidase A was normal in isolated leukocytes (56 nmol/mg; range, 33.2 to 109 nmol/mg), ruling out Fabry's disease. Clinical, morphological, and biochemical findings were consistent with chloroquine-associated deterioration of renal function that improved considerably after discontinuation of chloroquine treatment. Adverse effects of chloroquine may aggravate preexisting renal disease. Electron microscopy is a worthwhile tool for establishing the correct diagnosis.

Chloroquine↗
PubMed2002

Monoclonal gammopathy after low-grade MALT lymphoma: evidence for a second neoplasm.

We report the case of a patient with lymphoma of the salivary gland, at first diagnosed as lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) but later found to infiltrate the bone marrow. At diagnosis, the patient had a polyclonal increase of gamma-globulins. Five years after initial diagnosis, the patient presented with monoclonal gammopathy and infiltration of the bone marrow with neoplastic cells. Initially, the patient had received chemotherapy with different protocols (including etoposide, cyclophosphamide, fludarabin, methotrexate, and vincristine), none of which induced a lasting response. Therapy with rituximab (chimeric anti-CD20 monoclonal antibody) finally led to partial remission. Eighteen months after rituximab, progressive lymphoma in the abdomen and a monoclonal gammopathy developed. The bone marrow showed infiltration by lymphoplasmacytoid cells (monoclonal expression of the light-chain type lambda, positive for CD20, heterogeneous expression of CD45). The patient achieved another short clinical response with 4 cycles of the CHOP-protocol, but soon the lymphoma progressed again. Five years and 8 months after the initial diagnosis, the patient died from septicemia and progressive lymphoma. By polymerase chain reaction (PCR) for the IgH gene it was shown that lymphoma cells were initially oligoclonal in the salivary gland and, later, biclonal in the bone marrow. Sequencing of two bands of apparently same length showed that these manifestations of lymphoma were not identical. Taken together, our data show that the initial low-grade oligoclonal MALT lymphoma was no longer present and a more aggressive biclonal lymphoma with plasmacytoid differentiation had developed. The new lymphoma was clonally distinct and produced high amounts of monoclonal IgG lambda by immunoelectrophoresis. The relationship of the second lymphoma to the initial MALT lymphoma is discussed.

Antibodies, Monoclonal↗
PubMed2002

De novo missense mutation in a constitutively expressed exon of the slow alpha-tropomyosin gene TPM3 associated with an atypical, sporadic case of nemaline myopathy.

We describe an atypical case of nemaline myopathy with an unusual distribution of muscle weakness who presented at 14 years of age with kyphoscoliosis. In this patient, we demonstrate heterozygosity for a de novo CGT-CAT (Arg167His) mutation in a constitutively expressed exon (exon 5) of slow alpha-tropomyosin (TPM3). This is the first mutation identified in a constitutively expressed exon of TPM3 in a nemaline myopathy patient, but is similar to recently described mutations in beta-tropomyosin (TPM2) associated with nemaline myopathy and mutations in fast alpha-tropomyosin (TPM1) which cause hypertrophic cardiomyopathy.

Adenosine Triphosphatases↗
PubMed2002

[26-year-old female patient with elevated liver enzymes].

A 26-year-old woman presented with elevated liver enzymes, which were diagnosed two months ago. Examination revealed mild proximal muscle weakness, though the patient herself did not realise any impairment. The abdominal ultrasound and the histology of the liver remained unsuspicious. Muscle biopsy showed vacuolar degeneration, which could be ultrastructurally identified as large deposits of membrane-bound glycogen. The morphological findings prompted biochemical investigations which showed an excess of muscle glycogen. Acid maltase activity was reduced to < 10 % of normal, leading together with the clinical findings to the diagnosis of glycogenosis type II (Pompe's disease) of the adult type. Because of the modest impairment of the patient and the limited therapeutic possibilities, the patient remained thus untreated for.

Adult↗
PubMed2002

A case of idiopathic nodular glomerulosclerosis mimicking diabetic glomerulosclerosis (Kimmelstiel-Wilson type).

A case of idiopathic nodular glomerulosclerosis mimicking diabetic Kimmelstiel-Wilson glomerulopathy is reported. The patient was a 45-year-old man suffering from nephrotic syndrome. Light and electron microscopy revealed diffuse and nodular glomerulosclerosis indistinguishable from diabetic nodular glomerulosclerosis. Diabetes mellitus, however, had been excluded both by extensive clinical and by laboratory investigation. The differential diagnosis also included amyloidotic and non-amyloidotic fibrillary glomerulopathy, light chain glomerulopathy, collagen type III disease, immunotactoid glomerulopathy, and the sclerosing variant of membranoproliferative glomerulonephritis. Immunohistochemistry and ultrastructural investigations, however, excluded these entities, and the diagnosis of idiopathic nodular glomerulosclerosis was made. This variant has to be included in the differential diagnosis of nodular glomerulopathy associated with nephrotic syndrome.

Amyloidosis↗
PubMed2001

Cytochrome c oxidase deficiency due to mutations in SCO2, encoding a mitochondrial copper-binding protein, is rescued by copper in human myoblasts.

Mutations in SCO2, a cytochrome c oxidase (COX) assembly gene, have been reported in nine infants with early onset fatal cardioencephalomyopathy and a severe COX deficiency in striated muscle. Studies on a yeast homolog have suggested that human Sco2 acts as a copper chaperone, transporting copper to the Cu(A) site on the Cox II subunit, but the mechanism of action remains unclear. To investigate the molecular basis of pathogenesis of Sco2 defects in humans we performed genetic and biochemical studies on tissues, myoblasts and fibroblasts from affected patients, as well as on a recombinant human C-terminal Sco2 segment (22 kDa), bearing the putative CxxxC metal-binding motif. Recombinant Sco2 was shown to bind copper with a 1:1 stoichiometry and to form homomeric complexes in vitro, independent of the metal-binding motif. Immunohistochemistry using antibodies directed against different COX subunits showed a marked tissue-specific decrease in the Cox II/III subunits that form part of the catalytic core, consistent with the differential tissue involvement, but a more uniform distribution of Cox Vab, a nuclear-encoded subunit. Sco2 was severely reduced in patient fibroblasts and myoblasts by immunoblot analysis. Patient fibroblasts showed increased (64)Cu uptake but normal retention values and, consistent with this, the copper concentration was four times higher in Sco2-deficient myoblasts than in controls. COX activity in patient myoblasts was completely rescued by transduction with a retroviral vector expressing the human SCO2 coding sequence, and more interestingly by addition of copper-histidine (300 microM) to the culture medium. Whether the latter is accomplished by the very low residual levels of Sco2 in the patient cells, direct addition of copper to the Cu(A) site, or by another copper-binding protein remains unknown. Whatever the mechanism, this result suggests a possible therapy for the early treatment of this fatal infantile disease.

Amino Acid Motifs↗
PubMed2001

Deregulated expression of cell cycle-associated proteins in solid pseudopapillary tumor of the pancreas.

Solid pseudopapillary tumor of the pancreas was studied in a 20-year-old woman and a 54-year-old woman. In the younger patient, the tumor had metastasized to the liver 8 years after distal pancreatectomy. In both neoplasms, the distinct histologic pattern of solid, pseudopapillary, and degenerative cystic areas was present. Analysis by means of immunohistochemistry revealed a diffuse expression for vimentin, neuron-specific enolase, and a focal positivity for al-antitrypsin, whereas epithelial markers were negative in the tumor of the older patient and only focally expressed in the tumor of the younger patient. Immunohistochemical analysis of cell cycle-associated proteins provided an overexpression of cyclin D1 and cyclin D3 in both tumors, although to varying degrees. In addition, the cyclin-dependent kinase inhibitors p21, and to a lesser extent p27, were up-regulated just as mdm2. There was no accumulation of p53 protein, and Ki67-positive cells were extremely scarce. Analysis of the liver metastases showed an immunoreactive profile similar to that of the primary tumor. The results show a deregulation of the cell cycle with overexpression of cell cycle-activating proteins D1 and D3 and a probably counterbalancing upregulation of the cyclin-dependent kinase inhibitors p21 and p27. The findings may explain the low pool of Ki67-reactive tumor cells and the generally good clinical outcome of these tumors. Whether a more profound dysbalance of the cell cycle regulation is responsible for the development of metastatic disease remains to be clarified.

Biomarkers, Tumor↗