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Cerebrospinal fluid cytology in patients with brain tumors; a simple method using the cell culture technique.

A simplified cytologic method using the cell culture technique was employed in 71 cases with brain tumor. Neoplasitc cells were demonstrated in 17 cases (24%), that is in 11 out of 30 cases of glioma, four out of ten cases of metastatic brain tumor, and two out of 17 cases of meningioma. None of 14 other miscellaneous tumors proved positive. Identification of glioma cells could be easily made because they usually showed characteristic morphology and good proliferation in vitro. However, for other types of tumor, conventional methods were considered to be superior to the culture method because their exfoliated cells usually underwent rapid degeneration without showing characteristic morphology during the culture. Some of the illustrative cases were presented.

Adolescent↗
PubMed1978

The r.b.e. of different-energy neutrons as determined by human bone-marrow cell-culture techniques.

The effect of X-rays and different-energy neutrons on human bone-marrow cells was studied using two different cell-culture techniques--diffusion chamber (DC) growth and colony formation in vitro (CFU-C). Based on the survival of proliferative granulocytes in DC on day 13, the D0 value was 80 rad with X-rays, and 117 rad as measured by the CFU-C assay. The D0 values for neutrons depended on the radiation source and the energy level. The r.b.e. values, which dropped with increasing energy levels of mono-energetic neutrons, were (i) 0.44 MeV; DC 3.7, CFU-C 4.1; (ii) 6 MeV; DC 1.8, CFU-C 2.0; (iii) 15 MeV; DC 1.6, CFU-C 1.6; (iv) fission neutrons; DC 2.6, CFU-C 2.4.

Bone Marrow↗
PubMed1977

Evaluation of biologic effects of dental materials using four different cell culture techniques.

The cytotoxicity of fresh and 1-day-old silicate cement, composite restorative material and zinc oxide-eugenol cement (ZOE) was tested using human epithelial cells (NCTC 2544) in four different cell culture systems: (1) 51Cr-release from prelabeled cells after incubation for 4 and 24 h in the presence of the materials. (2) Implanting the materials on an agar everlay and visualizing any cytotoxic effects after 24 h by neutral red vital stain. (3) Cell growth during 5 d in the presence of the materials. (4) Colony-forming ability after exposure of the cells for 30 min to medium previously incubated with the materials for 24 h. Freshly prepared and 1-day-old ZOE exhibited a prominent cytotoxic effect in all four systems. A less marked effect was found for the composite material in systems 2, 3, and 4, while silicate cement appeared to be the least toxic material in these three systems. Neither silicate cement nor composite showed any cytotoxic effect in system 1 based on 51Cr-release. It is concluded that the effects obtained by the cell culture techniques did not mimic the reactions obtained when the materials are tested under conditions which reflect their clinical use.

Cell Division↗
PubMed1977

Biologic evaluation of filling materials. A comparison of results using cell culture techniques, implantation tests and pulp studies.

The paper presents a comparison of results from cell culture studies, implantation tests and pulp studies using silicate cement, composite material and zinc oxide/eugenol cement. The three techniques allow differentiation between reactions produced by the materials, but a poor correlation exists between the results from the different techniques. This information is considered important for a selection of techniques for biologic testing of dental materials.

Animals↗
PubMed1976

Examination of various cell culture techniques for co-incubation of virulent Treponema pallidum (Nichols I strain) under anaerobic conditions.

Treponema pallidum (Nichols virulent) was incubated with and without cells in cell culture medium reduced to -275 mV Ecal, pH 7.3, under deoxygenated conditions. Five to ten percent of the treponemes attached to cells and remained motile for at least 120 h in cell-treponeme systems of co-incubation. Virulent treponemes could be detected after 120 to 144 h in the supernatant fluids of cell-treponeme co-incubation cultures and in cell-free tubes containing medium harvested from aerobically cultivated mammalian cells. Medium supplemented with ox serum ultrafiltrate, pyruvate, and sodium thioglycolate and gas mixtures containing H2 and CO2 enhanced treponemal survival. Increases in treponemal numbers were observed using dark-field microscopy but were not substantiated using the rabbit lesion test. Continuous passage of the treponeme was not achieved in vitro.

Anaerobiosis↗
PubMed1976

Natural infection of pigs with bovine viral diarrhea virus and its differential diagnosis from hog cholera.

Natural infection of pigs with bovine viral diarrhea virus (BVDV) through contact with infected cattle has caused problems in diagnosing hog cholera (HC). Low cross-reacting serum antibody titers against HC caused by BVDV infection were found in clinically normal pigs as well as those suspected of having HC. Bovine viral diarrhea virus was isolated from specimen tissues and initially identified as HC virus (HCV), using the fluorescent antibody cell culture technique. Additional cell cultures, as well as pig and calf trials, were necessary to identify it as BVDV. The isolate caused clinical signs of illness in the calves, whereas the pigs remained healthy. Bovine viral diarrhea virus may be detected in tissue sections or isolated in cell cultures and confirmed as HCV, using the HC fluorescent antibody conjugate. Laboratories performing the neutralization test for HC should use discretion when interpreting HC titers unless BVD titers are determined on the same serums.

Animals↗
PubMed1976

An approach to human preleukemia using cell culture studies.

Cell culture methods applied to the study of acute leukemia have indicated the presence of many abnormalities. Utilizing this knowledge, we have applied cell culture techniques to the evaluation of a patient population with a recognized risk of developing leukemia. We demonstrate that cultural abnormalities present in some patients with sideroblastic anemia are similar to those seen in acute leukemia, and that these perturbations may be shown before leukemia develops. This study suggests that cell culture abnormalities may reflect mechanisms operative in vivo, and preceding the development of overt leukemia.

Bone Marrow↗
PubMed1977

Improved technique for electron microscopy of cultured cells.

A number of techniques are presented which precise selection and efficient preparation of individual cultured cells for electron microscopy. Techniques described include marking of the living and embedded cells, drilling and mounting cores of embedded material, and improved technique for marking of the selected area on the block face before trimming.

Cells, Cultured↗
PubMed1976

Cell and organ culture techniques applied to the study of carcinoma of colon and rectum.

The value of a number of in vitro systems which have been used in the investigation of carcinomas of colon and rectum is considered. Tissue culture cell ines which have been established from human and mouse rectal and colon tumours are described. Both mouse and human cells retain ultrastructural features of the tumours of origin; acinus formations, junctional complexes, microvilli with surface glycoprotein strands. Normal colo-rectal epithelium has not been established in cell culture but organ cultures of mouse colon, which retain normal ultrastructural features can be maintained for at least 28 days. The possible origin of non-epithelial cells which appear in cultures from normal colon is discussed. The areas in which the various in vitro systems may be of used are reviewed.

Animals↗
PubMed1977

Erythropoietic precursors in murine blood.

Murine blood was examined for circulating erythropoietic precursors. Blood mononuclear cells harvested using a slight modification of the Ficoll-Hypaque technique were cultured using the methylcellulose clonal cell culture technique. Only erythropoietic burst forming units (BFU-E) were present in the blood. Erythropoietin dose response studies revealed a progressive increment in the number of erythropoietic bursts up to a concentration of 4 U/ml of sheep plasma erythropoietin. A linear correlation existed between the numbers of nucleated cells plated and the erythropoietic bursts for both normal mice and mice with phenylhydrazine-induced (PHZ) anemia. No individual erythrocytic colonies were detected in cultures from blood taken before or after PHZ injections. These results suggest that erythrocytic colony-forming units (CFU-E) do not participate in the migration of erythropoietic precursors in mice.

Animals↗
PubMed1977

[Short and long term behaviour of pleural effusion cultures. (Report of 200 cases) (author's transl)].

Pleural effusions from 200 patients with benign or malignant pleural involvement have been cultured in vitro and observed from 48 hours to 9 months. The morphology and "social behavior" of the different types of cells are described. Mesothelial cells settle down quickly and come into contact with each other by long cytoplasmic processes. The tendency of epithelial malignant cells is to clump and grow in clusters. These "balls" of varying size are freed into the culture medium. Similar clusters may be found in benign effusions showing mesothelial hyperplasia. In case of malignant primary tumor of the pleura, the morphology of cultured cells is similar to that of mesothelial cells. In 3 cases, typical malignant epithelial cells have allowed us to discard the diagnosis of malignant mesothelioma. Discrepancies between conventional cytology and cell culture were found in 13 cases: in 6 cases, positive for malignant cells using conventional cytology, cell culture was negative. In 7 cases with negative routine techniques, cell culture disclosed malignant cells. Large multinucleated syncytia were observed in 15 cultures. They suggest a cytopathic effect similar to that seen in myxovirus infected cells. Correlation with the etiology of pleural effusions in these cases is described.

Cells, Cultured↗
PubMed1976

The Jeremiah Metzger lecture of The American Clinical and Climatological Association 1975. New genetic insight into old diseases.

With these three examples, examined in some detail, I have attempted to indicate new directions in medical genetics. Some of the recognizable generalities are the following: 1. With the application of cell culture techniques in the area called human somatic cell genetics, human genetics has become essentially an experimental science. Somaticcell studies have provided insight into genetic disorders that would not have been possible from studies in the whole organism. Even therapeutic possibilities can be explored. Somatic cell hyubridization has substituted for controlled matings in permitting linkage studies for mapping of the human chromosomes...

Androgen-Insensitivity Syndrome↗
PubMed1978

Mouse spleen lymphoblasts generated in vitro. Recovery in high yield and purity after floatation in dense bovine plasma albumin solutions.

Mouse spleen lymphoblasts, stimulated to divide in vitro, acquired a low cell density and could be separated by isopycnic techniques. Cultured cells were suspended in BPA columns, rho = 1.080, and spun to equilibrium. The method was simple, fast, accomodated large numbers of cells, and was reproducible. It provided lymphoblasts in high yield and purity (at least 80% of the low density cells were blasts). It allowed for the recovery of proliferating cells in their first cell cycle, and did not alter the subsequent ability of cells to proliferate when recultured in vitro. Certain properties of mouse spleen lymphoblasts were analyzed in detail. Lymphoblasts induced by LPS, FCS, con A (tetravalent and succinylated), and MLC were very similar except in the absolute numbers that were induced. The blasts exhibited the classic cytologic features of enlarged nucleoli and abundant cytoplasmic polyribosomes (basophilia). As a population, they were enlarged in size relative to nondividing cells, but this seemed to apply primarily to cells in the S and G2+ M phase of the cell cycle rather than G1. The cell cycle distribution of lymphoblasts was analyzed by flow microfluorometry. By analyzing low density cells obtained at varying intervals after mitogen stimulation, FMF indicated that lymphoblasts enter the S phase of their first cell cycle beginning at 20-24 h after stimulation.

Animals↗
PubMed1979

Characteristics of noncultivable adenoviruses associated with diarrhea in infants: a new subgroup of human adenoviruses.

Virus particles morphologically resembling adenovirus were found in fecal specimens from infants and were examined for cultivability with standard cell culture techniques and for characteristics of human adenoviruses. Specimens from 13 of 15 infants could not be cultivated in cell cultures. The two adenoviruses that were cultivated, types 1 and 31, reacted in the expected manner in all tests. Counterimmunoelectrophoresis with group-specific anti-hexon serum confirmed that the observed particles in the 15 specimens were human adenoviruses. The buoyant density in sucrose of five of the noncultivable adenoviruses in original stool suspensions averaged 1.335 g/cm(3) and that of the two cultivable ones averaged 1.332 g/cm(3); both groups had typical adenovirus morphology by electron microscopy. Treatment of the specimens and of a variety of tissue culture cells with proteolytic and other enzymes did not improve cultivability. Examination of partially purified virus by immunoelectron microscopy did not reveal evidence of immunoglobulin A, G, or M coating on the particles, an indication that coproantibody inhibition was not the cause of noncultivability. Fluorescent-antibody studies with an antihexon conjugate and counterimmunoelectrophoresis studies of serially passaged noncultivable viruses indicated that the viruses are infecting cells but are not undergoing effective replication. Antisera to three of the noncultivable viruses demonstrated homologous reactions in counterimmunoelectrophoresis with the respective immunizing antigens but showed only low levels of hemagglutination-inhibiting and neutralizing activity to a few of the known human adenoviruses. We concluded that the noncultivable viruses in these infant diarrhea cases were indeed human adenoviruses, were not defective particles, were not bound to coproantibody, were infectious but incapable of effective relication in conventional cell cultures, were serologically related to types 11, 17, 32, and 33, and should be considered a new, distinct subgroup.

Adenoviruses, Human↗
PubMed1977

Assays and dynamics of corticotropin-releasing factor activity in rat hypothalamus.

Features of several assays for corticotropin-releasing factor (CRF) were compared, with reference to sensitivity, precision, specificity and convenience. In general, in vivo assays are less specific, whereas in vitro assays with isolated pituitary cells appear to suffer from vulnerability. Promising approaches for overcoming this difficulty are appearing: one is the cell culture technique and the other is the perfusion of pituitary cell column. However, the findings with vasopressin are again discordant. So far, the in vivo-in vitro assay system appears to be the most satisfactory. In this connection, special emphasis was laid on the CRF assay by out intrapituitary injection technique through the parapharyngeal approach, which has features of both in vivo and in vitro systems. The drawbacks with this assay are its complexity and relatively lower precision. Problems of the use of dexamethasone are discussed from a viewpoint of possible multistage feedback inhibition, as postulated by Yates et al. Several findings on the CRF dynamics were mentioned, in order to exemplify the findings obtained with our assay: it was shown that the two-peaked changes of CRF after ether-laparotomy stress in adult rats were composed of heterogeneous components, as revealed by differential effect of cycloheximide. Pretreatment with cycloheximide similarly abolished the delayed CRF peak that was observed in 2-day-old neonatal rats under stress. These findings suggest an operation of a biochemical denominator in common with both cases.

Adrenocorticotropic Hormone↗