PubMed Health⌕ Search

Biomedical subjects

E Fuchs

Publications and source records attributed to E Fuchs.

At least 343 records · Page 19Linked to original sources
PubMed1983

The evolution and complexity of the genes encoding the cytoskeletal proteins of human epidermal cells.

In order to explore the differential expression and evolutionary conservation of the genes encoding the cytoskeletal proteins for human epidermal cells, we have constructed a library of bacterial plasmids containing inserts of double-stranded cDNAs complementary to the mRNAs of cultured human epidermal cells. Cloned hybrid plasmids containing 45-95% of the sequences present in keratin, actin, and tubulin mRNAs were isolated and characterized. To identify the cDNAs encoding the four major keratins of human epidermal cells, the clones were initially screened for their ability to hybridize strongly with 32P-labeled cDNA prepared from unfractionated epidermal mRNA (about 30% keratin mRNA). Strongly hybridizing clones were further characterized by positive hybrid selection. Two distinct classes of clones were identified: One class hybridized specifically to the 56 and 58kd keratin mRNAs and one class hybridized specifically to the 46 and 50kd keratin mRNAs. Each class is encoded by a separate multigene family of about 10 genes. The two classes of sequences are conserved throughout vertebrate evolution, indicating the functional importance of each class in filament assembly. Clones containing human cDNA sequences encoding a cytoplasmic actin and alpha-tubulin were selected by hybridization screening using 32P-labeled cloned cDNAs for the mRNAs of beta-actin and alpha-tubulin of embryonic chick brain. The identity of these clones was established by positive hybrid selection and by DNA sequence analysis. Similar to the keratins, the actins and tubulins are also encoded by multigene families which are highly evolutionarily conserved. The availability of cloned cDNAs specific for each of three types of epithelial cytoskeletal proteins allows us to investigate the coordinate expression of their mRNAs during terminal differentiation in human epidermis.

Actins↗
PubMed1982

Corticosteroid, catecholamine and glucose plasma levels in rabbits after repeated exposure to a novel environment or administration of (1-24) ACTH or insulin.

The responsiveness of the adrenal cortex and the sympatho-adrenal-medullary system to stress factors and administration of (1-24) ACTH and insulin was studied in adult rabbits. In comparison to untreated animals, exposure to a novel environment for 10 min followed by artery puncture on 6 consecutive days elicited a moderate increase of corticosteroid (C), norepinephrine (NE) and epinephrine (E) plasma levels. Intramuscular injection of 50 micrograms/kg body weight (1-24) ACTH increased C, NE and E plasma levels. Saline injection resulted in elevated NE levels; C, E and glucose remained unchanged. After injection of 1.0 IU/kg body weight insulin C levels were higher than those found after exposure to a novel environment for 10 min followed by artery puncture; similarly, NE and E increased. In accordance with results obtained in the rat or mouse the sympatho-adrenal-medullary system in the rabbit is stimulated by stress factors such as handling, artery puncture or injection of (1-24) ACTH or insulin. In contrast the adrenal cortex can be stimulated only to a certain extent by these manipulations. An increased activation of adrenal cortex cells occurs only after insulin, a maximum stimulation only after (1-24) ACTH administration.

Adrenal Cortex Hormones↗
PubMed1982

[Occupational allergens as a cause of obstructive lung diseases. Early diagnosis and clinical aspects].

Obstructive diseases of the respiratory tract caused by allergizing substances at the place of work must be classified as occupational diseases, provided certain conditions are fulfilled. The etiopathogenesis and special features of the clinical picture and diagnosis of occupationally conditioned allergic obstruction of the respiratory tract, previously known as bronchial asthma, are discussed. In contrast to "spontaneous" allergy, the occupational cause of the disease is due to often massive exposure to allergens at the place of work and the frequently aggressive potency of several industrial allergens, these being considered the actual "shaping" factors. The need for early diagnosis, as far as possible even at the initial "precursor" stage and during the manifestation of the so-called "equivalents", such as allergic conjunctivitis and rhinitis, is stressed. Treatment directed at removing the causes includes, fundamentally, prophylaxis against exposure (considering the time during which the allergens remain dormant without triggering an allergy); this obviously involves change of occupation or place of work, whereas specific treatment aimed at producing hyposensitization must remain an exception. The possibilities for prevention, chiefly from the medical point of view, are described.

Allergens↗
PubMed1982

The cDNA sequence of a human epidermal keratin: divergence of sequence but conservation of structure among intermediate filament proteins.

We have determined the DNA sequence of a cloned cDNA that is complementary to the mRNA for the 50 kilodalton (kd) human epidermal keratin. This provides the first amino acid sequence for a cytoskeletal keratin. Comparison of this sequence with those of other keratins reveals an evolutionary relationship between the cytoskeletal and the microfibrillar keratins, but shows no homology to matrix or feather keratins. The 50 kd keratin shares 28%-30% homology with partial sequences of other intermediate filament proteins, which suggests that keratins may be the most distantly related members of this class of fibrous proteins. Our computer analyses predict that the 50 kd keratin contains two long alpha-helical domains separated by a cluster of helix-inhibitory residues in the middle of the protein. These findings indicate that despite major sequence divergence among intermediate filament proteins, they retain sequences compatible with secondary structural features that appear to be common to all of them.

Amino Acid Sequence↗
PubMed1981

Regulation of terminal differentiation of cultured human keratinocytes by vitamin A.

Vitamin A is known to exert an important influence on epithelial differentiation. The fetal calf serum supplement of cell-culture medium contains enough of the vitamin to affect the differentiation of cultured keratinocytes derived from epidermis and from other stratified squamous epithelia. The cellular and molecular properties of the cultures are altered when the medium is supplemented with serum from which the vitamin A has been removed by solvent extraction (delipidized serum). Cell motility is reduced, the adhesiveness of cells increases and pattern formation is prevented. In both epidermal and conjunctival keratinocytes, removal of vitamin A leads to the synthesis of a 67 kd keratin characteristic of terminally differentiating epidermis and to much reduced synthesis of the 52 kd and 40 kd keratins typical of conjunctiva. These changes, both cellular and molecular, are reversed by the addition of retinyl acetate to the medium containing delipidized serum. Cell motility and pattern formation are restored, and detachment of the most mature cells from the surface of the stratified epithelium is promoted. Synthesis of the 67 kd keratin is prevented and the synthesis of the 40 and 52 kd keratins is stimulated. The nature of the keratins synthesized is regulated by the concentration of vitamin A, and each cell type adjusts its synthesis differently at a given vitamin concentration.

Cell Aggregation↗
PubMed1980

Stress hematuria: athletic pseudonephritis in marathoners.

Hematuria and proteinuria have been noted in athletes after heavy exercise. Evaluation of 383 marathoners after a 26-mile, 385-yard run revealed hematuria in 17 per cent and proteinuria in 30 per cent. These abnormalities were not related to sex. The condition is transient and appears to be benign. A diagnostic approach to avoid missing significant renal or urologic disease is outlined.

Female↗
PubMed1980

Management of postoperative pelvic lymphoceles.

Lymphoceles following pelvic surgery are not rare events. The management of this postoperative complication in 18 patients included needle aspiration, external drainage, and intraperitoneal marsupialization. The following diagnostic and therapeutic approach is recommended: ultrasonographic definition of the lymphocele; excretory urography to assess upper urinary tract obstruction; observation of small, nonobstructing, asymptomatic lymphoceles; needle aspiration for diagnosis confirmation; intraperitoneal marsupialization for noninfected, large lymphoceles that are obstructing the upper urinary tract or are symptomatic; and incision and drainage of small or infected lymphoceles.

Drainage↗
PubMed1980

Changes in keratin gene expression during terminal differentiation of the keratinocyte.

Cells of the inner layers of the epidermis contain small keratins (46-58K), whereas the cells of the outer layers contain large keratins (63-67K) in addition to small ones. The changes in keratin composition that take place within each cell during the course of its terminal differentiation result largely from changes in synthesis. Cultured epidermal cells resemble cells of the inner layers of the epidermis in synthesizing only small keratins. The cultured cells possess translatable mRNA only for small keratins, whereas mRNA extracted from whole epidermis can be translated into both large and small keratins. As no synthesis takes place in the outermost layer of the epidermis (stratum corneum), the keratins of this layer must be synthesized earlier, but in some cases they then become smaller: this presumably occurs by post-translational processing of the molecules during the final stages of differentiation. Stratified squamous epithelia of internal organs do not form a typical stratum corneum and do not make the large keratins characteristic of epidermis. Their keratins are also different from those of cultured keratinocytes, implying that they have embarked on an alternate route of terminal keratin synthesis.

Animals↗
PubMed1980

Demonstration of the early--late switch in vitro with bacteriophage T7 DNA as template.

A protein-synthesizing system in vitro, programmed with bacteriophage T7 DNA as template, changed the specificity of gene expression in the course of incubation as a result of newly synthesized T7 early proteins. The system mimics largely the situation in vivo on both the transcriptional and the translational levels, i.e. early gene expression is turned off shortly after late synthesis has been started. These results suggest that the switch from early to late expression does not necessarily require changes in the cellular environment nor is it dependent on the presence of membranes. The main part in this process is played by the phage-dependent RNA polymerase (gene 1 product), whose activity appears 8-10 min after start of incubation. When its activity is reduced by inhibitors or creation of non-optimal conditions, the system is not able to manage the early--late switch.

DNA, Viral↗