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Biomedical subjects

E Hartmann

Publications and source records attributed to E Hartmann.

257 records · Page 15Linked to original sources
PubMedDate not supplied

Correlation studies of morphological and biochemical parameters in human ejaculate in various andrological diagnoses. 3rd report. Correlations between morphological and biochemical parameters.

The result of a study of correlations between morphological and biochemical parameters in human ejaculate is presented in conclusion of an extensive study of these parameters. Basing on these results, for which a statistical significance of p less than 0.05 was calculated, it can be stated that higher fructose concentrations are associated with lower sperm density; at the same time, the higher fructose concentrations correlate with a higher percentage of non-motile and of pathologically changed spermatozoa. Similar associations can be established for certain substrates which result from fructolysis. The possibility of diffusion of enzymes from the cellular components must be considered as regards the increased activities of PGK, PGI and ATPase in seminal plasma in the presence of greater sperm density. Reliable conclusions about associations between morphological characteristics and enzyme activities can be expected in the future from appropriate measurements in the cellular elements (spermatozoa, round cells) of the ejaculate. The study results provide a further insight into the biochemistry of seminal plasma and into the associations between morphological and biochemical parameters in the ejaculate.

Acid Phosphatase↗
PubMedDate not supplied

Nuclear protein transport pathways.

Nuclear proteins like transcription factors and ribosomal proteins are synthesized in the cytoplasm and have to be transported into the nucleus to fulfill their functions. The transport of proteins >20-60 kD through the nuclear pore complex (NPC) into the nucleus is an active, energy-requiring process. Transport substrates are recognized by their transport proteins via certain signals. The best-characterized protein import pathway is the 'classical' nuclear localization signal-dependent pathway with importin alpha and beta carrying the substrate to the NPC. The transport of the importin-substrate complex into the nucleus is regulated by the small GTPase Ran/TC4. During the last years more than ten proteins have been discovered which have already been proven or are very likely to be nuclear transport factors of distinct import pathways: members of the importin alpha protein family are very similar and transport in complex with importin beta nuclear localization signal-bearing proteins into the nucleus. Members of the Ran-binding protein family show some weak similarity to importin beta. Sharing a common domain at the amino terminus, they are able to bind RanGTP, a prerequisite for their function as nuclear import or export factors for distinct proteins or RNAs. However, Ran/TC4 seems to play a key regulatory role in all nuclear transport pathways described so far, although the molecular mechanism of the translocation step through the NPC is still unclear.

Animals↗
PubMedDate not supplied

Sec61p is the main ribosome receptor in the endoplasmic reticulum of Saccharomyces cerevisiae.

A characteristic feature of the co-translational protein translocation into the endoplasmic reticulum (ER) is the tight association of the translating ribosomes with the translocation sites in the membrane. Biochemical analyses identified the Sec61 complex as the main ribosome receptor in the ER of mammalian cells. Similar experiments using purified homologues from the yeast Saccharomyces cerevisiae, the Sec61p complex and the Ssh1p complex, respectively, demonstrated that they bind ribosomes with an affinity similar to that of the mammalian Sec61 complex. However, these studies did not exclude the presence of other proteins that may form abundant ribosome binding sites in the yeast ER. We now show here that similar to the situation found in mammals in the yeast Saccharomyces cerevisiae the two Sec61-homologues Sec61p and Ssh1p are essential for the formation of high-affinity ribosome binding sites in the ER membrane. The number of binding sites formed by Ssh1p under standard growth conditions is at least 4 times less than those formed by Sec61p.

Endoplasmic Reticulum↗
PubMedDate not supplied

[Various aspects of a care system tuned to the requirements of those needing assistance].

The risk of becoming a nursing case dependent on care is one not covered by social insurance in the Federal Republic of Germany. The costs involved have to be borne by the individual needing care, his family or the respective public aid institution. The currently existing facilities for care, especially the nursing homes, are generally not considered acceptable and satisfactory by potential users. Social service provisions outside nursing homes are more widely appreciated, specially on account of the usual desire to retain a more independent and autonomous life style. Most inmates of nursing homes are dependent on public aid, considering the costs of these institutions. Fiscal burdens on public households in connection with providing public aid to persons in nursing homes have increased more than proportionately. Moreover the number of the very old aged who will be nursing cases with a very high probability is increasing. Taking into consideration the interest of the potential users as well as the economic restrictions, the use of existing in-patient nursing facilities in accordance with actual need, as well as the increase of out-patient service stations, seems to make an increase in the in-patient nursing facilities unnecessary. As prerequisite for this, however, in-patient care has to be restricted to those cases really requiring such care, and out-patient services must not altogether neglect criteria of efficiency.

Aged↗