bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrastructural Changes of Capillaries in Chronic Venous Insufficiency
Authors: Wenner A. , Leu H.J. , Spycher M. , Brunner U.
Published: October 2008

The ultrastructural changes of cutaneous and subcutaneous capillaries and venules in 6 cases of severe, chronic venous insufficiency were examined. The findings in all cases consisted of numerous and characteristic alterations of the vessel wall structure and of the pericapillary space which are supposed to be due to the increased intravenous pressure. The intercellular spaces are enlarged to wide channels through which erythrocytes pass into the perivascular spaces. Microvesicles occur in great numbers, they are arranged in chain-like formations and seem to come together to form transendothelial channels. Around the capillaries, edematous fluid with proteins and erythrocytes accumulates. Phagocytosis of erythrocytes, siderosomes and collagen fibrils by macrophages is observed. Within the endothelial cells there is an abundance of Weibel-Palade bodies and of multivesicular bodies. The former are frequently seen in contact with the luminal cell membrane. Weibel-Palade bodies are believed to be involved in the clotting mechanism.
Action of Interferon on Aged Chick Embryo Cells
Authors: Martin Brian A.B. , Kroath Hans , Jungwirth Christoph , Hofschneider Peter H. , Bodo Gehard , Wengler Gerd
Published: October 2008

In primary chick embryo cells aged in vitro, vaccinia virus replication is drastically inhibited by pretreatment with low doses of interferon. The antiviral state was established with doses about ten times smaller than those required with normal primary chick cells. Viral protein synthesis is also highly sensitive to chick interferon in these cells. Cell-free lysates from aged chick cells translated several viral and globin mRNAs efficiently. While drastic inhibition of vaccinia virus-specific protein synthesis by interferon treatment could be detected in the intact aged cells, the translation in the cell-free lysate was not significantly affected by pretreatment of the cells with interferon or interferon followed by infection with vaccinia WR.
Primary Immune Response of Mouse Spleen Cells in a Serum-Free System: the Role of 2-Mercaptoethanol
Authors: Burger M. , Hess M.W. , Cottier H.
Published: October 2008

The stimulatory effect of the combination of fetuin and 2-mercaptoethanol on the recovery of plaque-forming cells (PFC) in the absence of serum could be mimicked by the use of reduced alkylated fetuin. A correlation was found between the mitogenic and PFC-stimulating activities of reduced alkylated fetuin.
Cells Transformed by Transfer of Isolated Chromosomes from Virus-Transformed or ‘Spontaneous’ Tumor Cells
Authors: Persuy Marie-Annick , Ermonval Myriam , Suarez Horacio-G. , Daya-Grosjean Leela , Nardeux Pierre , Giovanella Beppino C. , Kay Alan C. , Cassingena Roland
Published: October 2008

13 cell lines obtained upon exposure of normal cells to chromosomes from virus-transformed (group A) or ‘spontaneous’ tumor cells (group B), besides displaying in vitro phenotype changes characteristic of transformed cells, are also capable (with two exceptions within group A) of producing progressively growing tumors in athymic nude mice. Of these lines, the possibility that they are donor-cell contaminants can be definitely, excluded in 10 cases, and there is some evidence against such a possibility in 2 of the 3 remaining lines. That these lines are recipient cells having undergone ‘spontaneous’ transformation can be excluded for group A but cannot be rigorously excluded for group B.
Quantitative Histochemical Changes in Intervertebral Discs in Diabetes
Authors: Aufdermaur Max , Fehr Kurt , Lesker Peggy , Silberberg Ruth
Published: October 2008

A comparison of the nuclei pulposi of 4 diabetic and 2 nondiabetic subjects disclosed a statistically significant decrease in hexosamine, a statistically significant increase of hydroxyproline, and significantly increased activities of four enzymes involved in the metabolism of carbohydrates. The results are considered preliminary in view of the small size of the sample.
Attempts to Transform Primate Cells in vitro by Herpes Simplex Virus
Authors: Marczynska B. , McPheron L. , Wilbanks G.D. , Tsurumoto D.M. , Deinhardt F.
Published: October 2008

Attempts were made to transform human cervical cells and nonhuman primate cells with herpes simplex virus (HSV). None of 129 cervical cell cultures obtained from 29 patients and infected in vitro with various strains of HSV became transformed. Established cell lines of marmoset cells infected with HSV showed no characteristics of malignant transformation. Parallel cultures of rat embryo cells maintained under similar experimental conditions became malignant.
Statistical Methods for Measuring and Comparing Treatment Efficacies: Applications to Nude Mice Experimentation
Authors: Lesser Martin L. , Braun Henry I. , Helson Lawrence
Published: October 2008

A method is proposed for measuring and comparing the growth over time of a sample of tumors subjected to a number of different therapies. The procedure, which is illustrated by means of an example, does not require explicit parametric modelling of the growth curve itself and is particularly useful when the comparison of treatment efficacies is of chief interest. In addition, an ad hoc approach to the estimation of required sample sizes is delineated.
Ultrastructural Changes in the Embryonic Cells of the Frog Microhyla ornata after Cytochalasin H Treatment
Authors: Wadekar Gauri , Dastur D.K. , Mulherkar Leela
Published: October 2008

Biological effects of cytochalasin H (CH), a newly isolated mould metabolite, have been found to bring about disaggregation of embryonic cells and to inhibit cytokinesis. Disaggregation is known to be a phenomenon related to the cell surface. (The cells are held together by a mucopolysaccharide glycoprotein complex.) In the present work the fact that the mucopolysaccharide glycoprotein surface coat gets affected by CH treatment is confirmed by electron microscopy with the help of Lanthanum, a specific marker, which gets selectively absorbed to the cell surface material and renders it electron dense. The ultra-structural observations indicated the reduction of the cell surface material in treated embryos as compared to the controls. The reappearance of lanthanum-bound cell surface material in the recovered embryos was also observed. However, the exact mechanism of the action of CH on the cell surface remains to be clarified.
Effects of Retinoic Acid on the Human Lymphocyte Response to Mitogens
Authors: Abb Jochen , Deinhardt Friedrich
Published: October 2008

Nontoxic concentrations of retinoic acid enhance DNA synthesis of human peripheral blood lymphocytes in response to phytohemagglutinin or rabbit-antihuman-thymocyte globulin, whereas the response to concanavalin A or pokeweed mitogen remained unaffected. Retinoic acid-induced stimulation of lymphocyte reactivity to phytohemagglutinin or antithymocyte globulin was most evident in T cell-enriched subpopulations and required the near-concurrent addition of retinoic acid and mitogens. Retinoic acid-mediated enhancement of lymphocyte proliferation in response to phytohemagglutinin or antithymocyte globulin was paralleled by a concomitant suppression of immune interferon production of lymphocytes stimulated with these mitogens. These findings allow further studies on the immunoregulatory action of retinoids in vitro.
Lymphokine Production in Primary Mixed Lymphocyte Reactions
Authors: Landolfo Santo , Di Matteo Carmen , Capusso Angela , Negro-Ponzi Alessandro , Forni Guido
Published: October 2008

The characteristics of the responder and stimulating cells involved in migration inhibition factor (MIF) production in primary ‘one-way’ mouse mixed lymphocyte reactions (MLR) were analyzed by using an indirect agarose droplet assay. T-lymphocytes are mainly responsible for MIF release, as shown by pretreatment with anti-Thy 1.2 serum plus complement or purification over a nylon wool column. On the other hand, macrophages and B-lymphocytes appear to be optimal stimulating cells. T-lymphocytes as stimulating cells induce MIF release, but to a much lesser degree than macrophages and B-lymphocytes. The kinetics of MIF production in MLR is related to the kind of stimulating cells employed. Lastly, the ability to release MIF is already present in the spleens of 1- to 2-week-old mice, lasts until 20 weeks of age and declines to undetectable levels at 50 weeks of age.
Generation of Antibody Diversity Subsequent to Antigenic Stimulation
Authors: Obel Jan
Published: October 2008

Experiments are presented in which spleen cells from donor mice, exhibiting a clonally very restricted early antibody response to a small RNA bacteriophage, are transferred at limiting cell dose into irradiated syngeneic recipients. Antibodies produced in such recipients were analyzed with regard to isoelectric points (pI’s). Most antibodies in the recipients were found to differ from the donor, but the pI range into which they fall is frequently fairly narrow and related to the pI of the donor. It is suggested that most recipient clones may be derived from a common ancestral precursor cell by somatic mutation in immunoglobulin genes, conceivably subsequent to antigenic stimulation. If such a process should indeed account for the observed diversity, it would imply an unusually high mutation rate.
Tumor Promoter Induces Loss of Anchorage Dependence in Human Skin Fibroblasts from Individuals Genetically Predisposed to Cancer
Authors: Kopelovich Levy , Bias Nancy E.
Published: October 2008

To examine the role of germinal mutation in transformation by phorbol esters, we studied the induction of anchorage-independent variants of mutant human diploid fibroblasts derived from normal-appearing skin of individuals with hereditary adenomatosis of the colon and rectum (ACR). Liquid cultures were chronically exposed to 12-0-tetra-decanoyl phorbol-13-acetate (TPA), then plated in agar and injected subcutaneously into athymic mice. Cultured ACR cells showed an unusual biphasic dose response to TPA. Colony-forming cells in agar were obtained at a frequency of about 5 × 10-5. They did not, however, seem to increase in frequency during subsequent passages in liquid cultures continuously exposed to TPA. The isolated anchorage-transformed clones showed an altered clonal morphology and a considerable increase in cloning efficiency in liquid cultures and agar. The results suggest that ACR cells may be used to screen for potential tumor promoters in our environment.
Cell Kinetic Study of Human Cancers Transplanted to Nude Mice
Authors: Ikeuchi Shunji , Shimosato Yukio , Kameya Toru , Watanabe Shaw , Kakegawa Teruo , Abe Osahiko
Published: October 2008

Using 3H-TdR pulse labelling, the cell kinetics of four, serially transplantable, human tumors were studied in athymic nude mice. Squamous cell carcinoma of the lung, tongue and esophagus showed relatively similar cell kinetic parameters. The growth of an oat-cell carcinoma was initially very slow in mice and its growth fraction was unexpectedly small with a relatively low labelling index. Its postmitotic phase was very short. It was concluded that the nude mice/human tumor system may be useful for cell kinetic studies of human tumors from the standpoint of tumor biology and therapy.
Twenty-Three New Human Tumor Lines Established in Nude Mice
Authors: Fogh Jørgen , Orfeo Thomas , Tiso John , Sharkey Francis E. , Fogh Jens M. , Daniels Walter P.
Published: October 2008

Subcutaneous inoculation of 87 human tumors into athymic nude mice, including gastrointestinal (non-colon) tumors, germ cell-primitive cell tumors, kidney tumors, lower urinary tract tumors, malignant melanomas and several metastases from unknown primary sites, resulted in growth in primary transplants in 32 cases (36.8%). Take rates varied among the tumor categories, from 56% for malignant melanomas to 13% for lower urinary tract tumors. They also differed among recurrent tumors (50%), metastases (41%) and tumors of primary site (28%). 23 tumor lines were established, including five lines each from renal cell adenocarcinomas and malignant melanomas, two each from adenocarcinoma of the pancreas and Wilms’ tumors and ony line each from various tumors of the gastrointestinal, germ cell-primitive cell, lower urinary tract and primary site unknown categories. The frequency of line establishment was greater for recurrent tumors and metastases than for primary tumors. Tumor lines have been carried continuously up to passage 17 in one case. Time in primary transplant varied from 3 to 29 weeks for the individual tumors and the average primary transplant time varied from 5.8 to 14.7 weeks for the six tumor categories. The average time in passage varied among the established lines from 2.3 to 10.6 weeks. The average passage time for all tumor lines was 5.3 weeks, with those of recurrent tumor origin showing the shortest average (4.0 weeks) followed by lines of metastatic origin (5.4 weeks) and those of primary tumor origin (5.8 weeks).
Durable Sensitization of Hormone Receptors during Differentiation in Regenerating Planarians by Treatment with Homologous or Analogous Hormone Molecules
Authors: Csaba G. , Kádár Magda
Published: October 2008

Hormonal (dopamine, epinephrine) treatment of planarians during total regeneration (sensitizing treatment) resulted in amplification of the receptors, which accounted for an increased response to later hormone exposure (provocative treatment). While not presensitized specimens showed an identical increase of glucose uptake upon provocative treatment with either hormone, dopamine proved to be more active than epinephrine regardless of homologous or analogous presensitization. The glucose-uptake-enhancing effect of dopamine was independent of the presensitizing dose level, whereas that of epinephrine was not, having increased as the presensitizer concentration was elevated. The experimental observations indicate that the hormone receptors may become modified, i.e. durably amplified, during the differentiation stage and that exposure of the differentiating receptor to a structurally dissimilar, analogous molecule may result not only in deformation, but also in amplification of the receptor.
Effects of Irradiation on the in vitro Immune Response
Authors: Anderson Robert E. , Lefkovits Ivan
Published: October 2008

Primed and unprimed murine spleen cells and suspensions enriched for T or B cells were exposed to various doses of radiation in vitro and evaluated with respect to their capacity to respond to sheep red blood cells (SRBC) in 1-ml or 10-µl cultures. The dose-response data show three components: (1) a low dose ( < 50 rad) phase associated with an augmented anti-SRBC response; (2) a radiosensitive phase associated with a precipitous loss of anti-SRBC activity; (3) a relative radioresistant phase with a loss of anti-SRBC activity which occurs over a broad range of radiation doses. Data obtained utilizing irradiated subpopulations enriched for T or B cells combined with excess numbers of nonirradiated lymphocytes of the corresponding cell type suggest that low dose augmentation is the result of radiation-induced injury to T cells or subcomponent thereof. With respect to the second component of the dose-response curve, similar experiments show that B cells are more radiosensitive than T cells (D37 of ∼ 80 vs. ∼220 rad, respectively) in this response. The third component of the curve appears to involve the interaction of radioresistant subpopulations of T and B cells.
Animal Model for Small Cell Carcinoma of the Lung. Effect of Immunosuppression and Sex of Mouse on Tumor Growth in Nude Athymic Mice
Authors: Pettengill O.S. , Curphey T.J. , Cate C.C. , Flint C.F. , Maurer L.H. , Sorenson G.D.
Published: October 2008

An animal model for the experimental study of small cell carcinoma of the lung (SCCL; human) has been developed. Tumors arising from continuous cell lines of cultured tumor cells as well as transplantable tumors of human SCCL in nude athymic mice have been characterized as to growth rate and morphology. The effect of antilymphocyte and antithymocyte sera and the sex of the host mouse were evaluated.
Clonal Differences in Generation Times of GPK Epithelial Cells in Monolayer Culture
Authors: Riley P.A. , Hola M.
Published: October 2008

Pedigrees of cells in eight clones of guinea pig keratocyte (GPK) cells in monolayer culture were analyzed from a time-lapse film. The generation times and the position in the field of observation were recorded up to the sixth generation when the cultures were still subconfluent. Statistical analysis of the results indicates that the position in the culture has less significance than the clonal origin of the cell in determining the interval between successive mitoses.
Age-Related Histochemical and Histological Changes in the Knee-Joint Cartilage of C57B1 Mice and Their Significance for the Pathogenesis of Osteoarthrosis
Authors: Pataki A. , Rüttner J.R. , Abt K.
Published: October 2008

For a better understanding of the part played by the aging of cartilage in the pathogenesis of osteoarthrosis, we attempted to detect functional age-related changes in the knee-joint cartilage of C57B1 mice using histochemical methods and to correlate these changes with the concomitant histological changes. A comparison of 57- and 97-week-old mice revealed a statistically significant age-related focal loss of activity for a number of oxidative enzymes of the chondrocytes. There was an associated significant increase in regressive changes of the chondrocytes. A relation probably exists between these two changes, inasmuch as the focal loss of enzyme activity precedes and possibly gives rise to the regressive changes. A comparison with the changes described in the articular cartilage of other species including man suggests that the phenomena observed are inherent age-related changes. The loss of activity of all the enzymes investigated indicates a far-reaching derangement of cellular metabolism, leading to impaired synthesis of proteoglycans. Since these compounds are major determinants of the physical properties of articular cartilage, the changes described might render the cartilage more vulnerable and might thus play a major part in the pathogenesis of osteoarthrosis.
Cryo-Ultramicrotomy as a Tool for the Assessment of Doxorubicine Cardiotoxicity in Rats
Authors: Holderegger C. , Zbinden G.
Published: October 2008

Cryo-ultramicrotomy was tested as a tool for the assessment of cardiac damage induced by doxorubicine in rats. Slightly fixed specimens were cut at – 80 or – 90 °C (knife temparature – 60 or – 70 °C), and the ultrastructural changes observed were compared with those found in conventional epoxy sections. It is concluded that the cryo method, although using more elaborate equipment and being more painstaking, might yield more sensitive parameters for cardiac damage than epoxy sections.
A Note on the Transformation of the dbrB Carcinoma
Authors: Fardon J.C. , Williamson D. , Freidel J.F.
Published: October 2008

A heterofore strain-specific mammary carcinoma of the mouse was found to have acquired altered characteristics. The dbrB transplantable tumor originated in a DBA mouse as a spontaneous carcinoma in 1918. It was not until recently, when this tumor was transferred from mice to storage in the frozen state, that a marked transformation occurred both in vivo and in vitro. Certain morphologic differences were also noted.
Possible Significance of Changes in the Energy Metabolism for the Release of Liver Lactate Dehydrogenase and for the Uptake and Incorporation of [14C]-Orotic Acid into Liver Ribonucleic Acid after Partial Hepatectomy
Authors: Yngner Torsten , Bengtsson Gun , Carlberg Elisabet , Engelbrecht Claes , Wieslander Anders
Published: October 2008

The mouse liver revealed no increased incorporation of [14C]-orotic acid into either the total acid-soluble fraction, the uridine triphosphate or the RNA at 6 and 24 h after partial hepatectomy. In regenerating mouse and rat liver, the concentration of adenosine triphosphate was decreased 15–20% at 6 h, but was in the same range as that of the controls at 24 h. The adenosine monophosphate concentration of mouse liver increased 4-fold and 2-fold at these times after partial hepatectomy, respectively. The results indicate no direct relationship between the energy metabolism and the uptake and incorporation of orotic acid into RNA of regenerating liver. The activity of mouse plasma lactate dehydrogenase 5 (LDH 5) was increased 12-fold at 6 h and 5-fold at 24 h after partial hepatectomy. In rat, the LDH 5 activity was increased 2-fold at 6 h but was not different from that of the controls at 24 h. An increased leakage of LDH 5, possibly related to the decreased energy content of the liver, was thus revealed by the partially hepatectomized mice.
A Correlated Thin Section and Freeze-Fracture Study of o-Phenylphenol-Induced Alterations in the Rat Liver
Authors: Robenek Horst , Meiss Rüdiger , Themann Hermann , Himmels Sabine
Published: October 2008

The ultrastructural changes in the liver cells of male Wistar rats induced by oral and subcutaneous application of o-phenylphenol were studied electron microscopically using the thin section and freeze-fracture technique. The rats were given the o-phenylphenol once at a dose of 2,500 mg/kg b.w. and were sacrificed 60 h after treatment. In the orally treated animals, alterations in the nuclei and nucleoli of the hepatocytes were the most prominent alterations. Furthermore, an increase in smooth endoplasmic reticulum, lysosomes and microbodies were found. After the subcutaneous injection of o-phenylphenol enlargements of the bile canaliculi, intercellular space and pathological alterations in the mitochondria were seen. A proliferation of the smooth endoplasmic reticulum, an increase of microbodies and a decrease in the rough endoplasmic reticulum could be found. Both groups showed an increase in small intracellular fat droplets in the hepatocytes. In general, the effects of the subcutaneous application on the liver were more pronounced than the effects of the oral application. Freeze-fracture replicas exhibited a disorganization of the zonulae occludentes and an apparent increase in the number and size of gap junctions. These alterations were interpreted as an attempt of the liver cells to counteract the intracanalicular pressure and to increase the mechanical stability of the liver tissue.
Induction of Syncytia by Simian Sarcoma Virus Type I (SSV-I/SSAV-I) in Several Human Transformed Cell Lines
Authors: Ocho M. , Ogura H. , Tanaka T. , Oda T.
Published: October 2008

Simian sarcoma virus type I (SSV-I/SSAV-I) induced syncytia formation in human cells derived from malignant tumors (KB, HEp-2 and HeLa cells) and human cells transformed by tumor viruses (RSa, RSb and KC cells) as well as rat XC cells. However, SSV-I/SSAV-I did not induce syncytia formation in human cells derived from normal embryos (WI-38, HEL and HEC). Syncytia-inducing activity of SSV-I/SSAV-I was neutralized by anti-SSV-I/SSAV-I serum, indicating that syncytia formation was SSV-I/SSAV-I mediated.
Thymocyte Reconstitution of Athymic and Athymic-Asplenic Mice: Graft Rejection and Antibody Synthesis
Authors: Lair Stephen V. , Lozzio Bismarck B.
Published: October 2008

Hereditarily athymic and athymic-asplenic mice were reconstituted with syngeneic thymocytes at various times prior to and after tumor challenge. These mice were able to reject heterotransplanted human tumors in as little as 19 days after thymocy te transfer but were unable to do so when the thymocytes were given 7 days after tumor implantation. The humoral immunity of athymic nude mice was fully restored as determined by the primary immune response to sheep erythrocytes (SRBC), a thymocyte-dependent antigen. Athymic-asplenic mice failed to respond to SRBC after reconstitution and this was attributed to the absence of the spleen in these mice.
Effect of Urethane on Folate Contents of Chick Embryos Measured with a Microbial Assay
Authors: Gokhale Vrinda , Mulherkar Leela
Published: October 2008

In earlier studies it was found that the effects of urethane could be reversed by folic acid and thymidine but not by uridine. It was further shown that urethane-treated chick embryos were unable to convert serine to glycine, homocysteine to methionine and uridine to thymidine, all of which are folate-dependent reactions. Due to the sensitivity of folic acid auxotrophs towards small amounts of folates present in the biological material, the folic acid contents of urethane-treated and untreated chick embryos are studied, using microbial assay. It is found that there is a statistically significant reduction in the total folate content of chick embryos treated with urethane as compared to those from the untreated controls. It is concluded that urethane has an antifolate action.
Procarbazine and CCNU as Initial Treatment in Gliomatosis Cerebri
Authors: Glas Martin , Rasch Katja , Wiewrodt Dorothee , Weller Michael , Herrlinger Ulrich
Published: October 2008

Background: Gliomatosis cerebri (GC) is a diffuse infiltrating glial tumor with involvement of at least 3 cerebral lobes. There are only few data on the efficacy of initial chemotherapy in patients with GC. Patients and Methods: In 3 neurooncological centers, patients with newly diagnosed GC who had received procarbazine (60 mg/m2, days 8–21/56) and CCNU (110 mg/m2, day 1/56) chemotherapy (PC) as initial treatment were analyzed for progression-free survival, overall survival and toxicity. Results: Twelve patients (median age 46 years, range 27–72) were analyzed. The median progression-free survival and the median overall survival were 16 and 37 months. Grade 3 or 4 hematotoxicity was observed in 3 of 12 patients (25%). Conclusions: These data support the efficacy of PC chemotherapy in newly diagnosed GC. Initial PC chemotherapy should be considered as a treatment option and evaluated in larger clinical trials.
Effects of Cadmium on Mouse Liver Polyribosome Function
Authors: Gamulin S. , Narancsik P.
Published: October 2008

The distribution of ribosomes between their various functional states (native subunits, unprogrammed ribosomes, monoribosomes and polyribosomes) was analyzed in livers of cadmium-treated (CdCl2 20 µmol/kg, 1 h) and control mice. The ribosomes with double-labelled RNA were separated by sucrose density-gradient centrifugation in zonal rotor, and monomeric ribosome fraction was subsequently isolated and analyzed by selective dissociation of unprogrammed ribosomes. The analysis shows that the increase in monomeric ribosomes, occurring during polyribosome disaggregation in livers of cadmium-treated mice, is entirely due to the increase of the unprogrammed ribosome fraction at the expense of polyribosomes. Protein synthetic activity of polyribosomes in vivo in livers of cadmium-treated and control mice were compared by double labelling of nascent and soluble polypeptides with [14C]-and [3H]-leucine. Incorporation of radioactivity was relatively higher in nascent polypeptides and lower in soluble polypeptides in cadmium-treated as compared with control mice. The results indicate that cadmium inhibits protein synthesis in livers of mice, affecting both the rate of initiation and the rate of elongation, but decreasing the former more than the latter.
Motoneuron Formation in the Brachial Spinal Cord of the Dystrophic Chick Embryo
Authors: Murphy B.J.
Published: October 2008

Motor neuroblasts comprising the brachial segments of the lateral motor column in the dystrophic chicken were counted at 6, 7, 9, 12, and 18 days of incubation and at 5 days’ post-hatching. Comparisons with similar counts from normal chick embryos disclosed that there was a significantly greater depletion of motor neurons in normal embryos between days 9 and 12. These findings suggest that nerve-muscle interaction may be altered early in the development of the motor unit in the dystrophic chick embryo.
Penetration of Asbestos Fibers in the Visceral Peritoneum of Mice
Authors: Winkler G.C. , Rüttner J.R.
Published: October 2008

Mice were injected intraperitoneally with either amosite, crocidolite or chrysotile. Tissue specimens of the mesentery (appendices epiploicae) were taken after 2 h, 24 h and 7 days and prepared for scanning electron microscopy. Subsequent examination revealed numerous fibers penetrating the mesothelium. The penetration is regarded as the earliest interaction between fibers and mesothelium and is due to the asbestos’ inherent needle-like structure and to visceral motility.
Steady-State Cultures of Human Skin
Authors: Kulesz-Martin Molly F. , McLimans William F.
Published: October 2008

Pretransplantation cultivation of adult human skin has been optimized for rapid and prolonged outgrowth of epidermal cells from tissue explants using automatic-perfusion, thin-layer culture technology (steady state). This system fostered growth of autologous mesenchymal elements via critical control of the culture environment. The resulting cellular outgrowth maintained a balanced epithelial–dermal relationship, contained keratinocytes as well as minority epidermal cells, melanocytes and possibly Langerhans cells. Critical control of culture pH and osmolarity was found to enhance epithelial cell proliferation.
Cultured Human Skin: Heterotransplantation
Authors: Kulesz-Martin Molly F. , Birnkrant Arthur , McLimans William F.
Published: October 2008

We have reported that human skin, cultured in a controlled environment system (steady state), yields epidermis-like growth from adult donor split thickness specimens. A procedure for transplantation of such cellular outgrowths to athymic nude mice for functional and morphologic evaluations is reported. Successful transplants were definitively scored by the presence of histologic epidermal markers and human glucose phosphate isomerase. We suggest that the transplantation procedures reported here may contribute to the knowledge required for the use of autologous cultured skin in patients with large skin wounds.
Clonal Evolution Demonstrated by Flow Cytometric DNA Analysis of a Human Colonic Carcinoma Grown in Nude Mice
Authors: Vindeløv Lars L. , Spang-Thomsen Mogens , Visfeldt Jakob , Povlsen Carl O. , Jensen Grethe , Nissen Nis I.
Published: October 2008

A spontaneous change in DNA content of a human colonic carcinoma grown in nude mice was observed fortuitously. The tumor initially had a Gl cell DNA content of 1.3 times that of normal cells. Flow cytometric DNA analysis showed in transplant generation 56 the appearance of a new subpopulation which in three passages completely overgrew the original population. The DNA content of the new subpopulation was twice that of the original population. The observation supports the hypothesis of clonal evolution of tumor cell populations. The growth rates of the tumor before and after the change showed no significant difference (p& > 0.05). Cell kinetic factors, therefore, offer no obvious explanation of how the overgrowth took place. It is not known whether the original population disappeared completely or survived as a small population below the detection limit. The heterogeneity created by clonal evolution of a tumor would be less pronounced if old subpopulations often become extinct as new ones emerge. Heterogeneity of human tumors is of clinical importance because the individual subpopulations may have different sensitivity patterns to antineoplastic drugs.
Function-Related Structural Characters and Their Modifications in the Hindgut Epithelium of Two Terrestrial Isopods, Armadillidium vulgare and Oniscus asellus
Authors: Coruzzi Laura , Witkus Ruth , Vernon Grace M.
Published: October 2008

Intercellular junctions of the hindgut epithelial cells of two terrestrial isopods, Armadillidium vulgare and Oniscus asellus, are described. Long septate desmosomes occupy the subluminal region while gap junctions, zonulae adherens and intercellular spaces characterize the remainder of the convoluted lateral cell borders. The specialized junctional complexes and the ultrastructural morphology of the cells indicate that the terrestrial isopod hindgut epithelium functions in transport. Using mitochondrial morphometry as an indicator of cell transport activity, it appears that the posterior hindgut of A. vulgare also participates in osmoregulation, which is not the case with O. asellus. With increased desiccation there develops a significant difference between the mitochondrial structure of the two species. The mitochondria of the former retain the active structural condition (intermediate condensed conformation) while those of the latter become swollen and damaged.
Stimulation and Membrane Charge Changes of Spleen Cells by Factors of Low Molecular Weight Associated with Murine Solid Tumors
Authors: Vaillier Dominique , Vaillier Jacques
Published: October 2008

Dialysates from a slow-growing VMM2 and a fast-growing RV2 solid murine tumor were fractionated on a Sephadex G-50 column. Similar elution profiles with two peaks were obtained in both cases. Fractions I and II, corresponding to these two peaks were tested for their mitotic properties on lymphocytes in culture and their effect on the negative surface charge of spleen cells by the electrophoretic mobility measurement (EPM) technique. Fraction I from both tumors presents a similar mitogenic action on C3H/He or nu/nu lymphocytes in culture. Incubation for 1 h at 37 °C of normal mice spleen cells with fraction I from RV2 or VMM2 tumors did not affect the mean electrophoretic mobility of spleen cells. Fraction II from VMM2 tumor induced a significant decrease in the mean electrophoretic mobility of spleen cells (-13.4%), while fraction II from RV2 tumor increases the EPM (+ 9%) significantly. Incubation with T cell-enriched or B cell-enriched populations or spleen cells from nu/nu mice shows that fraction II from VMM2 interacts with T cells but not with B cells. Fraction II from RV2 increases the T and B cell electrophoretic mobility.
Are All Normal Diploid Human Cell Strains Alike? Relevance to Carcinogenic Mechanisms in vitro
Authors: Kopelovich Levy
Published: October 2008

The present results suggest that studies on the oncogenic potential of normal diploid human cells in vitro should be qualified with respect to the stage of development and genetic constitution. For example, cultured normal human embryo and foreskin cells are phenotypically distinct from normal adult cells (5–65 years). The former appear to grow in culture in a fashion similar to that seen with initiated human mutant cells. They also exhibit a proliferative response pattern to a tumor promoter (TPA) closely resembling that obtained with human tumor cells. Thus, normal embryo and foreskin cells presumably represent a state in development which is genetically unstable, rendering them considerably more susceptible to malignant transformation. This conclusion may hold true with respect to spontaneously occurring tumors as well.
In vitro Screening of Carcinogens Using DNA of the His-Mutant of Salmonella typhimurium
Authors: Beljanski Mirko , Le Goff Liliane , Beljanski Monique
Published: October 2008

Carcinogens: 7,12-dimethylbenz(a)anthracene (DMBA), 2-acetylaminofluorene (AAF), 3-methylcholanthrene (MC), daunorubicin, thio-TEPA, cyclophosphamide, l-(2-chloroethyl)2-cyclohexyl-1 -nitrosourea (CCNU) and mitomycin C, which mutate Salmonella typhimurium tester strains in the Salmonella/’microsome mutagenicity test, strongly stimulate the in vitro synthesis of DNA isolated from His” mutants (TA-1538, TA-1537, TA-1535), and induce in vitro His- DNA strand separation. Four other carcinogens, ethionine, actinomycin D, bleomycin and reserpine, which were not known as mutagens in the Ames test, also strongly stimulate His– DNA synthesis and His– DNA strand separation in local areas. Those substances which are neither carcinogenic nor mutagenic: d-lactose, fluorene, cholesterol, and saccharin, do not stimulate either His– DNA (or His+ DNA) synthesis or DNA in vitro strand separation. Steroid hormones, which are carcinogenic only for steroid target tissues, do not react with bacterials DNA.
Early Fibrogenicity of Asbestos Fibers in Visceral Peritoneum
Authors: Winkler G.C. , Rüttner J.R.
Published: October 2008

Different asbestos types and milled asbestos cement were inoculated intraperitoneally into mice. Mesenteric tissue (appendices epiploicae) was examined by transmission electron microscopy at different intervals between 2 h and 3 weeks after exposure to asbestos. As early as 2 h after asbestos administration, the investigated tissues exhibited focal mesothelial cell loss baring the basement membrane, which at some points was even disrupted. Severe cell damage, obviously caused by the mineral fibers, was discernible in the remaining mesothelial cells. At a later stage, the whole peritoneal sheet underwent inflammatory and diffuse fibrotic processes. The early surface irritation is due to the mechanical influence of the penetrating asbestos fibers. The results confirm our previously published findings with the scanning electron microscope that asbestos has distinct fibrogenic properties.
Exogenous Fibronectin Requirement for Adhesion by Neoplastic Human Cells
Authors: Rajaraman R. , MacSween J.M. , Murdock C.A.
Published: October 2008

We have studied the effect of serum, plasma and plasma fibronectin on the spreading behavior of several normal and neoplastic human cells using a quantitative spreading assay. Normal human cells are rich in surface fibronectin and are able to spread in the absence of serum or exogenous fibronectin. Virus-transformed cells and cells of neoplastic origin have reduced or no recognizable surface fibronectin and are dependent on serum or plasma for spreading. In agreement with previous studies on rodent cells, fibronectin appears to be the major factor responsible for this effect. Neoplastic cells can spread on fibronectin-coated substrata or can recruit fibronectin directly from the medium. The capacity of transformed cells to recruit fibronectin from the medium correlates with the presence of intercellular fibronectin as seen by the immunofluorescence technique on monolayer cultures. Our results are in keeping with the concept that neoplastic cells may be dependent on extracellular fibronectin for adherence in vivo and that this dependency may vary between different cell types.
Phorbol Myristate Acetate-Induced Macrophage Aggregation
Authors: Badenoch-Jones P.
Published: October 2008

Phorbol myristate acetate (PMA) at nanomole concentrations induces a rapid aggregation of guinea pig macrophages. This aggregation is dependent on extracellular Mg2+ (but not Ca2+) for its development. Additionally, it is inhibited by some agents which also inhibit aggregation induced by lymphokines and the ionophore A23187. Although the mechanism of aggregation has not been determined, it does not appear to be related to either arachidonic acid metabolites or products of the respiratory burst. In this respect, it resembles the PMA-induced aggregation of neutrophils.
Cellular Specificity of the Cure for Neonatal Osteopetrosis in the ia Rat
Authors: Schneider Gary B. , Byrnes John E.
Published: October 2008

Osteopetrosis in the ia/ia rat is known to be the result of reduced bone resorption due to abnormal osteoclasts. Studies in this mutant have shown that mononuclear cells from normal littermates could cure the skeletal sclerosis and result in the formation of normal osteoclasts when transplanted into ia/ia rats. This investigation was pursued in an attempt to determine the cellular source of this cure by transplanting various populations of cells from 21 -day-old normal rats to unrelated newborn ia/ia recipients. The effects of treatment were evaluated radiographically and by measuring the size of the tibial marrow cavity. The cellular suspensions that were effective in curing the disease were the Ficoll-Hypaque isolate of spleen, bone marrow, and newborn livers. The Ficoll-Hypaque isolates of lymph node, thymus, and blood, and the adherent pool of peritoneal cells and splenic cells did not produce a cure in the ia/ia recipients. These results suggest that the cellular source of the cure is a stem cell. This conclusion is further substantiated by the finding that Thy 1.1 antigen (a stem cell marker in the rat) is expressed on a majority of the cells from the donor sources that affected a cure.
Blood Cells and Their Role in Regeneration
Authors: Sicard Raymond E.
Published: October 2008

The possible role of leukocytes in regeneration was examined through the evaluation of quantitative changes in circulating blood cell counts during forelimb regeneration in adult newts. Leukocyte counts declined during the first 2 weeks, then returned to preamputational levels. Thrombocytes were also depressed (40–67%) throughout the progressive stages (9–30 days). In addition, lymphocytes were reduced, especially during the preblastemic phase (<15 days). In contrast, neutrophils were increased immediately following wound healing and during the differentiation stages, but were otherwise unchanged. These variations appear to reflect physiological changes occurring during regeneration and are consistent with a potential role for leukocytes in regeneration.
Ultrastructure of Macrophages of the Murine Peyer’s Patch Dome
Authors: Hammer R. , Joel D.D. , LeFevre M.E.
Published: October 2008

The ultrastructure of macrophages located in the dome of murine Peyer’s patches was examined by transmission electron microscopy. Aggregates of carbon particles as well as numerous other phagocytic and lysosomal inclusions were consistently observed in dome macrophages of carbon-fed mice. Macrophages of both particle-fed and control mice exhibited morphological features of activation. Degenerating macrophages were observed, and evidence is presented that their disintegration involves invasion by other cells. The morphological findings are in accordance with other evidence that the Peyer’s patches receive an influx of material from the intestinal lumen. The potential importance of macrophages in the initiation of intestinal inflammations is emphasized.
Inhibition of Bone Resorption and Increased Incorporation of 3H-Glucosamine into Hyaluronate in Bone Organ Cultures Treated with Dibutyryl Cyclic AMP and Colchicine
Authors: Severson Arlen R.
Published: October 2008

Addition of dibutyryl adenosine 3’:5’-monophosphate (dcbAMP), colchicine or dbcAMP/colchicine to bone organ cultures markedly inhibited bone resorption. Calvaria of newborn mice labeled with 45Ca 3 days before sacrifice were removed and cultured in medium containing 3H-glucosamine. Both agents alone and in combination inhibited 45Ca release. DEAE-cellulose chromatography of the papain-digested medium and bone resolved the 3H-glucosamine-labeled macromolecular material into four peaks. A marked increase in radioactivity was observed in the hyaluronate fraction (peak III) of the chromatographed bone samples. The results indicate that dbcAMP does not mimic the effect of parathyroid hormone on bone resorption, but that it is similar to colchicine in both the inhibition of bone resorption and the increased incorporation of 3H-glucosamine into hyaluronate. Although the role of hyaluronate, if any, in this experimental system remain elusive, the increased radioactivity associated with the hyaluronate fraction may be due to decreased degradation resulting from decreased hyaluronidase synthesis.
The Role of Phosphatidylinositol Turnover in Initiation of Prostaglandin Biosynthesis in Concanavalin A-Induced Activation of Rat Peritoneal Macrophages
Authors: Matsubara Tsukasa , Hirohata Kazushi
Published: October 2008

When macrophages were stimulated by concanavalin A (50 µg/ml) in the presence of 32Pi and 3H-arachidonic acid (AA), rapid incorporation of these radiolabeled substances into phosphatidylinositol (PI) and phosphatidic acid (PA) were induced within 10 min. The pool of PI and PA incorporating 3H-AA was the same as that of PI and PA which incorporated 32P. However, significant increase in incorporation of 32P and 3H-AA did not occur in phosphatidylcholine, phosphatidylethanolamine or phosphatidylserine within this time interval as compared with control levels. These results indicate that PI turnover might play a role in the initiation of prostaglandin biosynthesis in the early stages of macrophage activation induced by concanavalin A.
Action of Adenosine Triphosphate on Human Skin and Gingival Fibroblasts
Authors: Hakim Anwar A. , Joseph Charles C.
Published: October 2008

If cultured in media supplemented with adenosine triphosphate (ATP), EDTA, trypsin, thrombin, or incubated at 0–15°C, human skin fibroblasts (HSF) and human gingival fibroblasts (HGF) change from long attached elliptical to round floating cell cultures. Also, if treated with ATP, EDTA, trypsin, thrombin, or incubated at 0–15°C, the attached HFS or HGF monolayers detach from plastic substratum and form floating round cells that progressively aggregate together and die. The described experiments examined the role of cellular and extracellular ATP on HSF and HGF attachment. These two types of fibroblasts differed in their cellular ATP levels and their response to metabolic inhibitors. ATP causes destruction of microtubules as monitored by colcemid uptake and cellular detachment. Fibronectin protects both HSF and HGF from the effects of extracellular ATP.
Blood Cells and Their Role in Regeneration
Authors: Sicard Raymond E.
Published: October 2008

The participation of leukocytes in regeneration was studied by determining changes in circulating leukocyte counts following putative immunological manipulations. Splenectomy failed to produce leukopenia during regeneration, although a 24–35% reduction in leukocytes occurred in otherwise intact newts. Bovine serum albumin and anti-lymphocyte serum produced initial lympho- and granulocytopenias, but blood counts soon returned to more normal levels. Lymphocytosis followed treatment with cobra venom factor, but marked lymphopenia occurred shortly thereafter. Regeneration occurred in all cases. These data failed to establish a clear correlation between the nature of quantitative changes in circulating leukocyte levels following these treatments and regenerative capacity.
Effects of Laminin, Fibronectin and Type IV Collagen on Liver Cell Cultures
Authors: Hirata Koichi , Yoshida Yutaka , Shiramatsu Koji , Freeman Aaron E. , Hayasaka Hiroshi
Published: October 2008

The effects on mouse liver cells of laminin, fibronectin and type IV collagen, all of which are the main matrix of the basement membrane, were studied. Laminin, a glycoprotein isolated from cultures of rat yolk sac carcinoma cells, promoted the attachment of mouse fetal liver cells to laminin-coated dishes, but did not have a strong influence upon the attachment of normal adult liver cells. On the other hand, fibronectin which was purified from mouse plasma promoted the attachment of adult liver cells but not that of fetal liver cells. The number of neonatal liver cells attached to the surfaces coated was intermediate between those of fetal and adult liver cells in each matrix. DNA synthesis and cell proliferation during the culture of full-term fetal liver cells in laminin-coated dishes were higher than those in fibronectin- or type IV collagen-coated dishes. The amount of alpha-fetoprotein secreted in the laminin-coated dishes was more than in other groups. No differences in secretion of albumin into media, however, were observed in either group. These results suggest that laminin may be necessary for cell growth, tissue organization and cell differentiation during the normal development of liver in vivo.