Biomedical subjects

H Grau

Publications and source records attributed to H Grau.

At least 19 recordsLinked to original sources

PubMed2000

Mammalian Sec61 is associated with Sec62 and Sec63.

In yeast, efficient protein transport across the endoplasmic reticulum (ER) membrane may occur co-translationally or post-translationally. The latter process is mediated by a membrane protein complex that consists of the Sec61p complex and the Sec62p-Sec63p subcomplex. In contrast, in mammalian cells protein translocation is almost exclusively co-translational. This transport depends on the Sec61 complex, which is homologous to the yeast Sec61p complex and has been identified in mammals as a ribosome-bound pore-forming membrane protein complex. We report here the existence of ribosome-free mammalian Sec61 complexes that associate with two ubiquitous proteins of the ER membrane. According to primary sequence analysis both proteins display homology to the yeast proteins Sec62p and Sec63p and are therefore named Sec62 and Sec63, respectively. The probable function of the mammalian Sec61-Sec62-Sec63 complex is discussed with respect to its abundance in ER membranes, which, in contrast to yeast ER membranes, apparently lack efficient post-translational translocation activity.

Amino Acid Sequence↗

PubMed1999

Effects of environmental conditions on microbial proteolysis in a pork myofibril model system.

A number of bacterial strains used for meat fermentations were screened for proteolytic activity. A strain of Micrococcus which was found to be proteolytic was evaluated for the effects of environmental conditions on its proteolytic activity against pork myofibrillar proteins using response surface methodology. Three strains of micrococci were also tested for the ability to produce free amino acids from pork myofibrils. Analysis of the effects of environmental conditions showed that proteolytic activity would be minimal under conditions normally found in fermented sausages, thereby suggesting that proteolysis in these products is largely due to endogenous meat enzymes. The three strains of micrococci were shown to produce free amino acids from pork myofibrils, thereby demonstrating the presence of peptidase activity in these strains.

Journal Article↗

PubMed1990

[Significance of computed tomography in ophthalmologic diagnosis. II. CT of eyeball tumors, orbital tumors, nontumor space-occupying orbital processes and malformations].

CT is valuable to complete ultrasound findings in the evaluation of tumors of the eyeball. Tumoral and nontumoral space-occupying lesions and malformations of the orbit and the exact demarcation of these conditions within the periorbital structures are well demonstrated. In several different pathological conditions the CT appearances are often similar and only sometimes characteristic. Additional clinical data are helpful in giving hints for the diagnostic differentiation of the CT findings.

Eye Neoplasms↗

PubMed1989

On the edema-preventing effect of the calf muscle pump.

During motionless standing an increased hydrostatic pressure leads to increased transcapillary fluid filtration into the interstitial space of the tissues of the lower extremities. The resulting changes in calf volume were measured using a mercury-in-silastic strain gauge. Following a change in body posture from lying to standing or sitting a two-stage change in calf volume was observed. A fast initial filling of the capacitance vessels was followed by a slow but continuous increase in calf volume during motionless standing and sitting with the legs dependent passively. The mean rates of this slow increase were about 0.17%.min-1 during standing and 0.12%.min-1 during sitting, respectively. During cycle ergometer exercise the plethysmographic recordings were highly influenced by movement artifacts. These artifacts, however, were removed from the recordings by low-pass filtering. As a result the slow volume changes, i.e. changes of the extravascular fluid were selected from the recorded signal. Contrary to the increases during standing and sitting the calf volumes of all 30 subjects decreased during cycle ergometer exercise. The mean decrease during 18 min of cycling (2-20 min) was -1.6% at 50 W work load and -1.9% at 100 W, respectively. This difference was statistically significant (p less than or equal to 0.01). The factors which may counteract the development of an interstitial edema, even during quiet standing and sitting, are discussed in detail. During cycling, however, three factors are most likely to contribute to the observed reduction in calf volume: (1) The decrease in venous pressure, which in turn reduces the effective filtration pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1989

[A rapidly expanding epithelial skull cyst of uncertain origin].

A rapidly expanding huge cystic lesion of the skull was the cause of unilateral exophthalmus in a 33 year old man. The differential diagnosis included an aneurysmal bone cyst, keratinous cyst, leptomeningeal cyst and intraosseous hemangioma. Although an epithelial lining was verified, the exact nature of the cyst could not be clarified despite immunohistochemical and electron microscopical investigations.

Adult↗

PubMed1989

[The significance of computed tomography in ophthalmologic diagnosis. I: The place of computed tomography, indications, study technics, anatomic representation, computed tomography of eyeball and orbital injuries].

CT is recognized today as method of choice for examining pathological conditions of eyeball and orbit. Several techniques of CT examination are needed to attain the most accurate and detailed information about orbital and eyeball lesions. The exact knowledge of the normal anatomic CT feature of orbital structures is necessary. In traumatic lesions of the globe and the orbit foreign bodies, haematomas and fractures of the orbital walls can be proved and localized and traumatic sequelae can be diagnosed.

Eye Foreign Bodies↗

PubMed1988