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U Uhlig

Publications and source records attributed to U Uhlig.

10 recordsLinked to original sources
PubMed2004

HOPE technique enables Western blot analysis from paraffin-embedded tissues.

In contrast to the spectrum of biochemical analyses of fresh material, that of archived specimens is widely restricted. Fixation of specimens with formalin, the most commonly used fixative, usually prevents further molecular analysis, since it leads to degradation of nucleic acids and denaturation of the antigenic determinants of proteins. To overcome these problems, the Hepes-glutamic acid buffer mediated Organic solvent Protection Effect (HOPE)-fixation technique has been developed, which preserves nucleic acids and antigenic determinants of proteins, thus expanding the applicability of immunohistochemical methods. In this study, we investigated whether HOPE-fixed tissue can be analyzed by Western blotting. Furthermore, a comparison with conventionally fixed and frozen material was made. The specimens used were tumor-free and obtained from lobectomies for lung cancer. All four antibodies tested, i.e., antibodies specific for focal adhesion kinase, surfactant protein A, PI-3-kinase, and IKKalpha, worked well if used for immunoblotting of HOPE-fixed and frozen tissue. By contrast, these antibodies showed no or only very weak specific binding if formalin-fixed specimens were analyzed. Our findings show that HOPE fixation maintains the antigenicity of proteins better than formalin fixation. The possibility for performing Western blotting with archived paraffin-embedded specimens extends the options for diagnostic and scientific analyses of fixed tissues.

Blotting, Western↗
PubMed2002

Ventilation-induced activation of the mitogen-activated protein kinase pathway.

Mechanical ventilation of patients can be a life-saving treatment, but also imposes additional stress on the lung. Mitogen-activated protein kinases (MAPK) represent a family of protein kinases that become phosphorylated and activated by many different forms of stress. Using Western blot analysis, the present study analysed the effects of high distending pressure ventilation on the activation of the MAPK extracellular signal-related kinases (ERK)-1/2, c-Jun amino-terminal kinases (JNK) and p38 kinase, and on the MAPK-activated transcription factors c-Jun, ETS-like protein (Elk)-1 and activating transcription factor (ATF)-2. In adult rats, ventilation with high pressure (45/10 peak inspiratory pressure/positive end-expiratory pressure in cmH2O) for 30 or 60 min did not affect arterial oxygenation, but resulted in enhanced phosphorylation of ERK-1/2, JNK, c-Jun, Elk-1 and ATF-2 compared to normally ventilated (13/3) rats. The activation of ERK-1/2 and JNK was located to cells resembling alveolar type II cells. In addition, high pressure ventilation enhanced phosphorylation of the inhibitor of nuclear factor (NF)-kappaB and nuclear translocation of the transcription factor NF-kappaB. In isolated perfused mouse lungs, the MAPK/ERK kinase inhibitor U0126 prevented ventilation-induced activation of ERK-1/2 and Elk-1, but had no effect on ventilation-induced cytokine release. The present authors conclude that mechanical ventilation triggers specific signalling pathways, such as the mitogen-activated protein kinase and the nuclear factor-kappaB pathways, which may contribute to pulmonary inflammation and proliferation.

Analysis of Variance↗
PubMed1996

Case report: splenic hamartoma with hematologic disorders.

Hamartomas of the spleen are rare benign tumors usually detected as asymptomatic, incidental findings at laparotomy or autopsy. By review of the literature, there are only 16 well-documented cases of symptomatic splenic hamartomas associated with hematologic disorders. The authors report on an additional case of splenic hamartoma in a 34-year-old man with thrombocytopenia. Findings by ultrasonography and computed tomography suggested multiple confluent splenic lesions. Because of progressively increasing thrombocytopenia, elective splenectomy was performed. Final pathology confirmed diagnosis of multiple hamartomas of the red pulp. Platelet count returned to normal within 1 month postoperatively. Differential diagnosis, diagnostic procedures, and pathologic findings of splenic hamartomas will be discussed. Hamartomas should be kept in mind in the differential diagnosis of splenic tumors. Splenectomy is indicated in cases where malignancy cannot be excluded and in cases of associated hematologic disorders.

Adult↗
PubMed1996

The influence of computer tomography on treatment strategies and follow-up in tumors of the nasopharynx and the paranasal sinuses. A retrospective study on 104 patients.

BACKGROUND: The high value of computer tomography (CT) for detailed imaging of nasopharyngeal and paranasal sinus tumors is known. Less known is the influence of such diagnostic findings on decisions of the therapist. An analysis of this influence might help to compare the value of CT and MRT. PATIENTS AND METHODS: We performed a retrospective study on 104 treated patients with malignant tumors of the nasopharynx (n = 54) and the paranasal sinuses (n = 50). The study analyzed the influence of CT on primary tumor diagnosis, tumor staging, treatment decision, therapy planning, detection and time of recurrences and retreatment of relapses. RESULTS: Tumors of the nasopharynx: The value of CT for tumor staging was 76% but there was no influence on treatment decision. Radiotherapy planning was influenced in 37% of cases. CT for follow-up was done in 22% of cases. Most relapses occurred within the first 2 years. Paranasal sinus tumors: There was no influence of CT on primary diagnosis of the tumor. Tumor staging was influenced by CT in 94%, treatment decision in 44% and radiotherapy planning in 60%. CT control immediately after therapy was of value in 40%. Most relapses were found within 3 years but some in the 4th and 5th year. Some patients survived 3 to 9 years after retreatment. CONCLUSIONS: In tumors of the nasopharynx there is less influence of CT on therapy strategies than diagnostic radiologists might think. No CT is needed for treatment decision since radiotherapy is the only choice of treatment. CT influenced radiotherapy planning however, in about 1/3 of our cases answering sufficiently the 2 main questions: tumor spread into the anterior half of the facial skull or involvement of the base of skull. The retreatment of recurrences detected by CT showed poor results. Late recurrences seem to have better prognosis. We recommend therefore routinely 1 basic CT 6 months after primary treatment followed by 1 CT yearly from the 3rd to 5th year. MRT might offer more diagnostic details than CT. However, at present therapy is not influenced much by this. Since CT is cheaper and faster, MRT could be discussed as additional procedure when CT presents equivocal findings and this fact could be decisive for therapy planning. Paranasal sinus tumors: The influence of CT on tumor-staging and treatment decision is high and convincing. CT helps also at radiotherapy planning and control of tumor response after therapy. CT has high value in detecting recurrences. Retreatment could control disease in some of our patients for 3 to 9 years. Better results could be achieved possibly with earlier diagnosis of recurrence. We propose therefore a basic-CT 6 months after first treatment and 1 CT routinely from the 2nd to 5th year. From the therapist's point of view we recommend CT as first imaging procedure in sinonasal tumors. MRT, more time- and cost consuming, should be applied when CT is equivocal and treatment decision could be influenced.

Follow-Up Studies↗
PubMed1995

[Magnetic resonance tomography in eclampsia].

Eclampsia is a rare but severe complication during the course of a pregnancy. The CT-findings at the brain are well known. Reports on MRT-findings are limited, however, especially in German literature. We describe the MRT picture of the cerebral changes caused by eclampsia and discuss the advantages of MRT in comparison with CT. The use of contrast agents with MRT shows breakdown of blood-brain barrier but does not provide any information of therapeutical consequences and should be avoided during pregnancy. An early and targeted use of MRT in any case of unclear or suspicious neurological symptoms during pregnancy is recommended. MRT supports differential diagnosis regarding non pregnancy-related cerebral disease and can be helpful for therapy planning in cases of preeclampsia. Additionally, MRT offers the possibility to control the effect of therapy with regard to brain damage.

Blood-Brain Barrier↗
PubMed1993

[Bronchogenic cyst as a rare differential diagnosis of retroperitoneal tumor].

A retroperitoneal tumor originating from a bronchogenic cyst is an extreme rarity. We report the sixth case of a retroperitoneal bronchogenic cyst in an asymptomatic 38-year-old man who was initially admitted to hospital due to elective herniotomy of a right-sided inguinal hernia. Excluding symptomatic hernia by preoperative, routine-ultrasound we detected left-sided adrenal tumor mass. Computerized tomography and inconspicuous hormone-analysis completed preoperative evaluation. A tumor with 3 cm in diameter above the left adrenal gland, partly solid, partly cystic could be removed by laparotomy incision without complications. Final pathology confirmed diagnosis of a bronchogenic, dysontogenic cyst. Although rare, these cysts should be considered in differential-diagnosis of retroperitoneal tumors.

Adrenal Glands↗
PubMedDate not supplied

A nonspecific, single-stranded nuclease activity with characteristics of a topoisomerase found in a major grass pollen allergen: possible biological significance.

The major allergen from timothy grass pollen, Phlp5b (Phleum pratense), was shown to exhibit ribonuclease activity. It turned out that the C-terminal portion of this molecule was the biologically active domain. Here evidence is presented that the allergen is a single-stranded, sugar-nonspecific nuclease with topoisomerase activity. An isomerase-specific active site was identified, and a non-active mutant was constructed by site directed mutagenesis, and showed no nucleolytic activity. In contrast to the wild type (WT), the mutant did not dimerize. Although the binding capacity of IgE antibodies toward the mutant was reduced as compared to the WT, the allergenic activity was retained. We conclude that the allergen Phlp5b is a single-stranded nuclease with an unusual topoisomerase-like activity. This biological activity is not by itself connected to the allergenicity of the molecule. Whether the enzymatic activity is responsible for the induction of the allergic sensitization and inflammation remains an open question.

Allergens↗