Production of platelet-derived growth factor-like molecules and reduced expression of platelet-derived growth factor receptors accompany transformation by a wide spectrum of agents

A series of nontransformed human and murine cells and derivative cell lines transformed by methylcholanthrene; by simian virus 40, Kirsten and Moloney murine sarcoma viruses, simian sarcoma virus, and adenovirus; and by a "spontaneous" event in culture were examined for the expression of receptors for the platelet-derived growth factor (PDGF) and for production of substances able to compete with 125I-labeled PDGF for binding to the cell-surface PDGF receptor. In each case, transformation resulted in a 50-100% decrease in available PDGF receptors. All transformed cells except the methylcholanthrene-transformed mouse cells produce a PDGF competitor into the conditioned medium. Levels of PDGF competitor in conditioned medium at the end of a 48-hr collection were as high as 2 ng/ml--high enough to be measured by radioreceptor assay diluted 1:30 and to maximally stimulate [3H]thymidine incorporation by human fibroblasts. The PDGF competitor activity detected in a radioreceptor assay does not reflect irreversible (e.g., proteolytic) damage to the receptor of test cells since its effects are reversed by acetic acid dissociation. Antiserum against human PDGF neutralizes 20-80% of the PDGF competitor found in conditioned medium from different transformed human cells and 100% of the activity from normal human endothelial cells. The possibility that induction of expression of the cellular PDGF gene may be involved in the mechanism of transformation of PDGF-responsive mesenchymal cells is discussed.

[Hair cylinders]

Hair casts (peripilar keratin casts) of two girls are investigated by electron microscopy. The 31 cases of hair casts so far known are briefly summarized. The etiology seems to be heterogeneous. The ultrastructural study of the casts reveals three layers. Two of them can easily be interpreted as internal root sheet, the third with parts of the outer root sheet, rather than with parts of the epithelium of the follicular infundibulum, as was suggested by Kligman in 1957.

[Development of Achilles tendon rupture in skiing]

This is an analysis of decline of rupture of the Achilles tendon in skiing while there is a steady increase of skiing injuries. Three groups, equipped with three different types of ski boots were observed once on a plane slope on the other hand on a bump track. The simultaneous size of angle of knee and ankle was measured by telemetry. The high plastic ski boot, which obstructs the ankle forward and lateral is apart from the rise of heel in the boot, the safety binding and the new skiing style the main reason for decline of rupture of the Achilles tendon in skiing.

Hyperpigmented small spots induced by long-term PUVA therapy. A clinical, light and electron microscopic study

Among 308 photochemotherapy (PUVA)-treated patients, 15 psoriatics and 1 case of mycosis fungoides developed persistent disseminated hyperpigmented small spots at the trunk and limbs as a side effect of the therapy. The histological, histochemical and electron microscopical studies performed on 5 of the patients revealed a greatly increased number of melanocytes in the macules, hyperactivity of the melanocytes and increased transfer of pigment to dermis and keratinocytes. Moreover, binucleated cells were found as well as multifarious signs of melanocytic damage in varying degrees. Similar alterations but less pronounced were observed in the intermacular skin. Some of the changes could be recognized even 7 months after the treatment had been stopped. The PUVA spots are compared with other etiologically light-dependent hyperpigmentations.

[Systemic cutis laxa-like pseudoxanthoma elasticum]

According to Pope the pseudoxanthoma elasticum (PXE) can be divided into four types using clinical genetical criteria. In contrast to the classical form the recessive type II is not only characterized by a wrinkeled appearance and laxity of the skin, furthermore there are no clinical symptoms indicating visceral disease. We report two patients with cutis laxa-like skin. In addition the patients suffered from pathological changes of the eye. In one of them an alteration of the peripher vascular system could be observed.

[Examination of tear film by specular microscopy (author's transl)]

The examination of tear film by specular microscopy enables various phenomena to be observed in normal and irritated eyes. In cases of dry eye syndrome some differentiations are possible.

Evidence for two forms of reverse transcriptase in human placenta of a patient with breast cancer. Purification and biochemical characterization of the enzymes

Two DNA polymerases with properties of viral RNA-directed DNA polymerase were found in the placenta of a patient with breast cancer. Both enzyme activities were purified by column-chromatographic procedures or by preparative isoelectric focusing. The most distinguishing feature of the two enzymes is their specificity to transcribe (rA)n . (dT)12 or (rC)n . (dG)18. The two enzymes differ with respect to their elution profiles from the phosphocellulose column, isoelectric point, molecular weight, bivalent-cation requirements and thermal stability. Serological analysis of the (rA)n . (dT)12-activated enzyme showed that this enzyme is immunologically not related to DNA polymerase-gamma, or to any of the reverse transcriptases purified from retroviruses of avian, murine and subprimate origin. However, the activity of this enzyme was neutralized by antibodies to reverse transcriptase purified from human spleen of a patient with myelofibrosis [Chandra & Steel (1977) Biochem. J. 167, 513-524]. Attempts to purify reverse transcriptase of normal human placenta were repeatedly unsuccessful. Once the crude homogenate of normal placenta was freed from endogenous nucleic acids, no (rC)n . (dG)18-dependent activity cold be detected.U

[Herlitz, severe generalized atrophic epidermolysis bullosa. Description and genealogic clarification of 4 new cases from Unterwalden canton]

Four infants with congenital epidermolysis bullosa letalis Herlitz were admitted between 1971 and 1978 to the Children's Hospital, Lucerne. All four were from three related families from the same valley in the Canton of Unterwalden and died before the age of one year. Histological and ultrastructural examinations of skin specimens confirmed the diagnosis, but an attempt to detect heterozygous carriers by the same method failed. Genealogical analysis revealed a fourth affected family one generation back and multiple consanguinity among three of the four families, according to an autosomal-recessive inheritance. The pathogenesis, clinical findings, therapy and genetics in this disease are discussed, together with the particular population genetics of the area concerned.

Role of serum components in density-dependent inhibition of growth of cells in culture. Platelet-derived growth factor is the major serum determinant of saturation density

The effects of platelet-derived growth factor and plasma components on saturation density in cultures of 3T3 cells were investigated. Both of these components of whole blood serum affect saturation density; however, when 3T3 cells become quiescent at high density in medium containing whole blood serum, only platelet-derived growth factor and fresh whole blood serum are capable of stimulating proliferation. Addition of fresh plasma- derived serum has little effect on cell growth. These results suggest that the platelet factor is the major determinant of saturation density in cultures of 3T3 cells maintained in medium supplemented with whole blood serum. Experiments were performed to investigate the mechanism by which platelet-derived growth factor regulates saturation density. We investigated the possibilities of inactivation of growth factors by proliferating cells, and the effects of cell density on the response of 3T3 cells to platelet-derived growth factor. The amount of platelet- derived growth factor required to initiated DNA synthesis increases with increasing cell density. Some inactivation of growth factors by growing cells was detected, but this depletion was only evident at high cell density. We propose that density-dependent inhibition in cultured 3T3 cells is the result both of an increased requirement for the platelet- derived growth factor as the cultures become more crowded and of inactivation of growth factor activity by growing cells.

[The Werner syndrome]

Werner's syndrome, also known as "progeria adultorum", manifests itself in young adults. They appear older than their chronological age. Characteristically, there is atrophy in the distal extremities and the face. There is progressive scleropoikiloderma and hyperkeratosis on the foot soles. In the face, there is frequently a "bird-like" expression. Other characteristics are premature graying and early loss of hair, juvenile cataracts, hypogonadism, diabetic symptoms, arteriosclerosis, osteoporosis, small stature with characteristic features, muscle atrophy and cardiac abnormalities. The disease is inherited in an autosomal recessive way. Pathogenesis is unclear. In the following paper, we are reporting the case of a 29 year old saleswoman, who complained of cramps in the calves, and presented the typical symptoms of Werner's syndrome.

Abnormal collagen fibril structure in the gravis form (type I) of Ehlers-Danlos syndrome

The Ehlers-Danlos syndrome (EDS) is a clinically, genetically, and biochemically heterogeneous group of disorders characterized by generalized connective tissue abnormalities. We studied collagen fibrils by electron microscopy in the dermis of nine individuals with clinical findings consistent with type I Ehlers-Danlos syndrome. In all patients the collagen fibrils had an increased mean diameter (13 to 40%) and showed a higher degree of variability in width and shape than collagen fibrils from controls. Approximately 5% of the fibrils were much wider (up to 500 nm. versus 90 nm.), had a highly irregular outline when viewed in cross-section, and were spiraled and fragmented in longitudinal view. The periodicity of banding was normal. The mode of inheritance was dominant in five patients, probably recessive in two, and could not be determined in the remaining two. Despite genetic heterogeneity among these patients with type I Ehlers-Danlos syndrome, the ultrastructural findings are indistinguishable and do not allow discrimination in sporadic cases between the recessive and the more common dominant form. We conclude that abnormalities of fibrillogenesis are heterogeneous in origin; some might be due to primary defects in collagen whereas others may result from alterations of noncollagenous extracellular matrix components that influence collagen fibril formation.

Single cilia in the articular cartilage of the cat

Single cilia (SC) in the articular cartilage of the cat are described with regard to structure, frequency and intracellular location. Comparison is made with their occurrence in the cartilage of other species or in other tissues; special consideration is given to their developmental stages. In the 1-year-old cat examined, about 20% of the cells showed SC with a predominantly intracellular course and some of them did not reach the extracellular space at all. Cross-sections of the proximal region of SC reveal the familiary 9+0 pattern; towards the distal end, the number of doublets and the diameter of the shaft are decreasing. It is concluded that most of the SC encountered are undergoing involution.

Coordinate control of 3T3 cell proliferation by platelet-derived growth factor and plasma components

DNA synthesis and cell division were measured in Swiss mouse 3T3 cells cultured in different concentrations of cell-free plasma-derived serum and increasing amounts of a platelet-derived growth factor. In plasma-derived serum alone, the cells were quiescent and they were arrested in the Go/G1 phase of the cell cycle. Addition of a platelet-derived growth factor to quiescent cells maintained in plasma-derived serum stimulated both DNA synthesis and cell division. When plasma components were present at high concentration (5%, vol/vol), the amount of platelet factor added to the cultures determined the number of cell doublings. Plasma-derived molecules were required for the platelet factor to stimulate DNA synthesis and cell division in the maximal number of cells. In addition, plasma components had to be present for recently divided cells to respond to the platelet factor. When 3T3 cells were cultured in excess platelet factor and limiting amounts of plasma-derived serum (0.5%, vol/vol), the cells underwent one doubling and then ceased to proliferate. Addition of fresh plasma-derived serum to these cells induced a second round of cell division. Plasma components and the platelet-derived growth factor acted in a coordinate fashion to regulate the proliferation of Swiss 3T3 cells.

Elastic fibers in the tunica propria of the seminiferous tubules. Light and electron microscopic investigations

Histological examination of numerous biopsies from mature testes, repeatedly showed irregularities of the elastin staining in the tunica propria of the seminiferous tubules. Even when abundant elastic fibers were visible by light microscopy, no elastic fibers were demonstrable in the electron microscope in ultrathin sections of testicular tubules embedded in Epon and contrasted with phosphotungstic acid (PTA). In 43 biopsies from 22 men aged 17-39 years (19 investigations of sterility and three patients with hypogonadotropic hypogonadism) we therefore checked for the occurrence of elastic fibers in the wall of the seminiferous tubules. Matrix loci of elastic fibers could indeed by demonstrated by electron microscopy using PTA and potassium permanganate (KMnO4), but only after embedding in araldite. Under these conditions, light and electron microscopic findings agreed with each other. The appearances of moderate and severe testicular tubular atrophy differed slightly from one another with regard to the amount of elastin. In the "Sertoli cells only syndrome", elastic fibers were demonstrable only outside the hyalinized inner layer. In the Klinefelter syndrome, only "uncertain" elastin loci were present, but greatly increased microfibrils were to be seen using the electron microscope. No elastic elements and only very sparse microfibrils were present in the tunica propria of the tubules of young men with hypogonadotropic hypogonadism.

[Evaluation of epithetic restoration]

Starting from an analysis of facial prostheses applied during the years 1967-1977, the authors report of the therapeutical success. The evaluation involved not only objective criteria but also psychical problems of the face-injured patients. Priorities of stomatological efficacy are established with regard to insertion, adaptation and the postadaptive phase.

[Plasma concentrations after injection or infusion of phenytoin (author's transl)]

Intravenous injection of 3 mg/kg phenytoin produced plasma concentrations of 4.2 mug/ml in five volunteers, which were below the concentration of 10-20 mjg/ml necessary for effective antiarrhythmic and antiepileptic treatment. Intravenous injection of 250 mg phenytoin followed by infusion of 750 mg phenytoin in a mean dosage of 1.7 mg/kg x h in nine patients with epilepsy produced plasma concentrations of 10.2 resp. 15.1 mug/ml after 4 resp. 8h. An oral maintenance therapy of 5-6 mg/kg is suggested. Therapeutic plasma concentrations were rapidly reached with this regimen.

Ehlers-Danlos syndrome in two siblings with deficient lysyl hydroxylase activity in cultured skin fibroblasts but only mild hydroxylysine deficit in skin

Two siblings suffered from Ehlers-Danlos syndrome characterized by skin fragility, joint laxity and dermal hyperelasticity. The association with microcornea and muscle hypotonia allowed the preliminary classification into type VI according to McKusick. Ultrastructure analysis of skin biopsies revealed poor integration of collagen fibrils into fibres; accordingly, the texture of the connective tissue appeared irregular. Lysyl hydroxylase activity of cultured skin fibroblasts was markedly reduced in the cells of the two patients. Preliminary studies revealed intermediate activity in the cells cultured from the skin of the parents. This finding suggested an autosomal recessive mode of inheritance. Unexpectedly and in contrast to the 3 cases reported in the literature, the hydroxylysine deficit in the patients' skin was, for reasons not yet understood, only mild. Therefore, amino acid analysis of skin is not adequate for the diagnosis of lysyl hydroxylase-deficient Ehlers-Danlos syndrome type VI.

Isolation and characterization of revertant cell lines. VII. DNA synthesis and mitotic rate of serum-sensitive revertants in non-permissive growth conditions

The ability to synthesize DNA and enter mitosis was studied in Balb/c and Swiss 3T3 cells, SV40 and MSV-transformed 3T3 cells and revertants of these transformed cells in cultures of different serum concentrations and cell densities. Three ways were found by which cells were able to maintain a constant cell number in non-permissive growth conditions: cessation of DNA synthesis, synthesis of DNA coupled with failure to enter mitosis, and the slow traverse of the cell cycle coupled with cell shedding. Growth control of the revertant of an MSV-transformed Balb/3T3 cell most closely resembled that of Balb or Swiss 3T3. This line did not grow in 1% serum and did not synthesize DNA in either non-permissive condition. Serum-sensitive revertants of SV40-transformed 3T3 cells are also unable to grow in 1% serum and also do not grow beyond confluence in 10% serum, but these cells differ from 3T3 in the manner in which this growth arrest is accomplished. In 1% serum, revertants synthesize DNA but do not enter mitosis. At confluence in 10% serum, they slowly traverse the cell cycle, with dividing cells replacing cells that are shed into the medium.

Isolation and characterization of revertant cell lines. VI. Susceptibility of revertants to retransformation by simian virus 40 and murine sarcoma virus

The susceptibility of two classes of revertants of Simian virus 40 (SV40)-transformed 3T3 cells to retransformation by SV40 or murine sarcoma virus (MSV) was studied. Both serum-sensitive and density-sensitive revertants are not retransformable by SV40. MSV can transform both types of revertants. The MSV-transformed revertants grow to high cell densities and form colonies when suspended in semi-solid methylcellulose medium, but are unable to grow in 1% calf serum. The MSV-transformed revertants produce infectious MSV and murine leukemia virus and possess the same number of chromosomes as the untransformed revertants.

Selection of revertants of Kirsten sarcoma virus transformed nonproducer BALB-3T3 cells

Revertants of Kirsten sarcoma virus transformed nonproducer BALB/3T3 cells (KA31 cells) were isolated after exposing the transformed cells to 5-fluorodeoxyuridine at high cell density, or when suspended in methylcellulose. Revertants were also isolated by treating KA31 cells with the lectin, concanavalin A, which is manyfold more toxic to transformed cells than for normal cells. The revertants resemble BALB/3T3 cells in their morphology and growth characteristics in that they have a low saturation density, fail to grow in 1% calf serum or when suspended in methylcellulose, and cease to synthesize DNA after reaching their saturation density. Infection by murine leukemia virus rescues Kirsten sarcoma virus from only the concanavalin-A-selected variants, though all the revertants are susceptible to infection by leukemia virus. The concanavalin A revertants also become transformed after infection with murine leukemia virus. All the revertants can be transformed by Kirsten sarcoma virus but not by simian virus 40.

Intracellular cyclic AMP concentration responds specifically to growth regulation by serum

Intracellular concentrations of cyclic AMP increase when cells are deprived of serum. Studies with the mouse fibroblast line 3T3, an SV40-transformed subline of 3T3, and six different revertant lines derived from this clone show that a marked increase in cyclic AMP occurs only when the serum concentration is reduced below the minimum necessary for growth of a given line. Conversely, density-dependent inhibition of growth is not accompanied by an increase in cyclic AMP concentration in any line.

Functional evaluation of an inherited abnormal fibrinogen: fibrinogen "Baltimore"

The rate of clotting and the rate of development and degree of turbidity after addition of thrombin to plasma or purified fibrinogen from a patient with fibrinogen Baltimore was delayed when compared with normal, especially in the presence of low concentrations of thrombin. Optimal coagulation and development of translucent, rather than opaque, clots occurred at a lower pH with the abnormal fibrinogen than with normal. Development of turbidity during clotting of the abnormal plasma or fibrinogen was less than normal at each pH tested, but was maximal in both at approximately pH 6.4. The physical quality of clots formed from fibrinogen Baltimore was abnormal, as demonstrated by a decreased amplitude on thromboelastography. The morphologic appearance of fibrin strands formed from fibrinogen Baltimore by thrombin at pH 7.4 was abnormal when examined by phase contrast or electron microscopy, but those formed by thrombin at pH 6.4 or by thrombin and calcium chloride were similar to, though less compact, than normal fibrin. The periodicity of fibrin formed from fibrinogen Baltimore was similar to normal and was 231-233 A.A study of the release of the fibrinopeptides from the patient's fibrinogen and its chromatographic subfractions verified the existence of both a normally behaving and a defective form of fibrinogen in the patient's plasma. The defective form differed from normal in three functionally different ways: (a) the rate of release of fibrinopeptides A and AP was slower than normal; (b) no visible clot formation accompanied either partial or complete release of the fibrinopeptides from the defective form in 0.3 M NaCl at pH 7.4; and (c) the defective component possessed a high proportion of phosphorylated, relative to nonphosphorylated, fibrinopeptide A, while the coagulable component contained very little of the phosphorylated peptide (AP). The high phosphate content of the defective component did not appear to be the cause of the abnormality, but may be the result of an associated metabolic or genetic phenomenon.