bluuebunny/crossref_metadata_2025_split huggingface dataset:
IN VITRO DIFFERENTIATION OF VIRULENT AND ATTENUATED POLIOVIRUSES BY THEIR GROWTH CHARACTERISTICS ON MS CELLS
Authors: Kanda Yukishige , Melnick Joseph L. 
Published: June 2004

The MS character of polio-virus particles is described. Strains that produced relatively large plaques, up to 6 mm. in diameter, on a monkey stable (MS) cell line, were classified as MS+. Such strains were found to include the highly virulent poliovirus strains. Attenuated strains appeared deficient in this gene, for they produced tiny plaques less than 1 mm. in size, or no visible plaques at all; they were considered as MS mutants.
Strains of maximum neurovirulence for the monkey possessed the MS+ and d+ characters, while those of greatest attenuation were MS d. Strains possessing the MS d+ character showed high or intermediate attenuation.
Virulent strains grew equally well in MS or primary monkey kidney (MK) cells. Attenuated strains gave lower titers in MS cultures than in MK cultures. While MS cells after infection with a virulent virus yielded about 100 to 200 PFU per cell, only one PFU per MS cell was detected after infection with an attenuated virus.
A study of newly isolated Type 3 strains showed them to consist of the MS+d+ or MS d+ type. The MS+d+ virus proved to be highly paralytogenic for monkeys even by the intramuscular route, while the MS d+ virus was of the partially attenuated type.
The study of in vitro characters of viruses from children fed attenuated poliovirus offers a possibility for following genetic changes of the viruses after multiplication in the human enteric tract.
DEPLETION OF RESERVE PROTEIN FROM EXTRAVASCULAR EXTRACELLULAR FLUID
Authors: Yuile C. L. , Lucas F. V. , Neubecker R. D. , Cochrane C. G. , Whipple G. H. 
Published: June 2004

During protein depletion produced by plasmapheresis and a very low protein diet there is a proportionately greater decrease in extravascular, extracellular fluid protein than in plasma protein.
A shift in the normal ratio of protein in these 2 compartments, approximately 1 to 1 in the dog, to over 2 to 1 as a result of depletion indicates an important, labile source of reserve protein for the plasma in the interstitial fluids.
This reserve source is limited since a maximum drop of 50 per cent in the total exchangeable pool and of 75 per cent in the extravascular, extracellular protein occurred after both shorter and longer periods of depletion. Under the rigid conditions of these experiments additional plasma protein removal was associated with loss of weight despite adequate caloric intake.
Investigation of the status of the interstitial fluid proteins in other conditions associated with disturbed protein metabolism seems warranted.
SEPARATION AND CHARACTERIZATION OF HUMAN SERUM CHYLOMICRONS
Authors: Scanu Angelo , Page Irvine H. 
Published: June 2004

Chylomicrons were separated by low and high speed ultracentrifugation from lipemic sera of human subjects in the absorptive phase. The final chylomicron preparation was free from other serum components and contained a small constant amount of protein, approximately 2 per cent of the chylomicron fraction. Electrophoresis, immunochemical analysis, and absorption experiments identified the protein component as derived from a mixture of beta and alpha1 serum lipoproteins.
Large aliquots of an emulsion of serum freed of chylomicrons and coconut oil were incubated at 37°C. for 2 hours and ultracentrifuged as in the preparation of chylomicrons. The fat particles now showed the presence of minute amounts of beta and alpha1 serum lipoproteins in almost the same proportion as found in chylomicrons. "Finger prints" of delipidized samples of chylomicrons and particles from serum-coconut oil emulsion gave similar, although not identical patterns.
The data on "clearing factor" activity corroborated the finding that serum alpha1 lipoproteins are contained in chylomicrons and particles from serum-coconut oil emulsion. These two lipide particles, partially delipidized, were both able to activate a "clearing factor" system in vitro, a property exhibited only by intact or partially delipidized alpha1 serum lipoproteins. Clearing activity was satisfactorily determined by using an emulsion of coconut oil mixed in agar as a substrate to give an opaque gel, in which the diffusing enzyme showed its activity by areas of clearing. The results obtained by this technique were in agreement with those based on fall in optical density and non-esterified fatty acid production.
Chemical analysis of serum chylomicrons showed a concentration of cholesterol and phospholipides higher than could be accounted for by the attached beta and alpha1 serum lipoproteins.
On the basis of these results the assumption is made that in the blood stream small amounts of serum lipoproteins, by a process of adsorption, form a complex with the absorbed triglycerides, cholesterol, and phospholipides, to produce chylomicrons.
STUDIES ON TUBERCULIN FEVER
Authors: Hall Charles H. , Atkins Elisha 
Published: June 2004

Evidence has been presented that the fever elicited by intravenous administration of old tuberculin (O.T.) in BCG-infected rabbits is a specific property of this hypersensitivity system and is probably not due to contamination of tuberculin with bacterial endotoxins. Daily injections of O.T. in sensitized animals resulted in a rapid tolerance to its pyrogenic effect. Tuberculin tolerance can be differentiated from that occurring with endotoxins and was invariably associated with the development of a negative skin test. The mechanism of this tolerance would thus appear to be desensitization.
A circulating pyrogen found during tuberculin fever was indistinguishable in its biologic effects from endogenous pyrogens obtained in several other types of experimental fever. This material produced fevers in normal recipients and therefore may be clearly differentiated from O.T. itself which was pyrogenic only to sensitized animals. Since the titer of serum pyrogen was directly proportional to the degree of fever induced by injection of O.T. in the donor animals, a causal relation is suggested.
On the basis of these findings, it is postulated that tuberculin fever is due to a circulating endogenous pyrogen released by a specific action of O.T. on sensitized cells of the host.
STUDIES OF MOUSE POLYOMA VIRUS INFECTION
Authors: Rowe Wallace P. , Hartley Janet W. , Estes John D. , Huebner Robert J. 
Published: June 2004

Three procedures have been compared for usefulness in titration and detection of polyoma virus: production of cytopathic effect (CPE) in mouse embryo tissue culture, production of HI antibody after inoculation into weanling mice (MAP test), and production of tumors in suckling hamsters during a 3 to 5 week observation period. The tissue culture and mouse antibody production tests were generally comparable in sensitivity, reproducibility, and time required to obtain results. Titration by tumor production in suckling hamsters was not suitable for quantitation because of marked variation in susceptibility among animals.
Virus was detected in tissues of normal mice from spontaneously infected colonies by either production of CPE in mouse embryo tissue culture or by the MAP test; virus was found in organs of 15 (58 per cent) of 26 mice with antibody, and 2 (8 per cent) of 24 mice without antibody.
STUDIES ON THE FORMATION OF COLLAGEN
Authors: Gross Jerome 
Published: June 2004

The skin of severely scorbutic guinea pigs which were losing weight contained no detectible neutral salt-extractible collagen.
Conditions of growth (weight gain) which actively induced the formation of neutral salt-extractible collagen in the skin of normal guinea pigs failed to do so in the animal with ascorbic acid deficiency.
No excess of non-collagenous proline was found in neutral salt extracts of scorbutic skin as compared with normal.
Fractionation of these extracts failed to reveal the presence of significant amounts of a soluble component containing unusual proportions of glycine and proline relative to hydroxyproline.
It is concluded that deficiency of ascorbic acid either interferes with the synthesis of new collagen in intact skin or causes its destruction and removal as rapidly as it is produced.
STUDIES ON STREPTOCOCCUS PYOGENES
Authors: Slade Hutton D. , Kimura Yoshitami 
Published: June 2004

Heat-killed cells of Group A streptococci caused death of the adrenalectomized rat. While the adrenalectomized rat readily succumbed to intraperitoneal infection with living cells, death was due primarily to toxicity. The normal rat was highly resistant under either condition.
For studies on the toxic materials, the cells of numerous serological types of group A streptococci, and of a Group B and a Group D streptococcus, were extracted with 0.1 N HCl at 100°C. or by sonic oscillation. The extracts, containing macromolecular components, were subjected to chemical fractionation and purification.
C substance and M protein of Group A streptococci released from the cell by sonic oscillation were toxic to the adrenalectomized rat in quantities of 1 mg./100 gm. rat. Death usually occurred within 2 hours. On the other hand, C substance and M protein released from the cell with HCl at 100°C. were relatively non-toxic to the adrenalectomized rat. The sonic-extracted C substance of streptococcal Groups B, C, and D was also toxic.
The toxic property of the C and M preparations was neutralized in vitro in each case by group and type-specific rabbit antiserum. Heterologous antiserum was without effect. Adrenalectomized rats which received homologous antiserum 18 hours before challenge were also resistant to the toxicity of the C and M preparations.
Trypsin destroyed the toxic effect of the M protein preparations and was without effect on the toxicity of the C substance.
The R antigen and a nucleoprotein component of Group A streptococci, preparations of protein from Groups B and D streptococci, and coagulase from Staphylococcus aureus were all found to be essentially non-toxicic for the adrenalectomized rat. Large quantities of peptone, crystalline albumin, and rabbit serum were also without effect.
EFFECT OF HUMAN BLOOD SERUM ON TISSUE CULTURES
Authors: Fedoroff S. , Cook B. 
Published: June 2004

When NCTC clone 929 (strain L) cells were grown either continuously or at intervals in toxic human serum, they became resistant to the toxic substance or substances.
The resistance developed to toxic human serum was passed from one cell generation to another; i.e., it was heritable.
The resistance to toxic human serum, developed in strain L cells, was associated with a decrease in their ability to adsorb toxic substances from the serum. This suggests that there is a decrease in the number of loci in the resistant cells where toxic substances can be bound.
The resistant cells differed from the sensitive cells in their morphological appearance, the increased frequency of minute chromosomes, and the increased adhesion to glass surfaces.
The cells which developed a resistance to a particular toxic serum also resisted the toxic effects of some other sera, but not of all.
STUDIES OF THE HEMOLYSIS OF RED BLOOD CELLS BY MUMPS VIRUS
Authors: Soule David W. , Marinetti Guido V. , Morgan Herbert R. 
Published: June 2004

Hemolysis of chicken red blood cells by mumps virus is associated with the release of sphingomyelin from the stromal lipoprotein and the destruction of 65 per cent of the sphingomyelin of the red cell stroma. However, the virus had no effect on isolated phosphatides extracted from the erythrocytes. The hemolytic action of the virus and changes in sphingomyelin content of the erythrocytes fail to occur at a pH of 6.0. The viral hemolysis of human erythrocytes is not associated with similar alterations in their content of sphingomyelin. The absence of lecithin from sheep erythrocytes, which are also lysed by mumps virus, is additional evidence that a viral lecithinase is not associated with the hemolytic property of mumps virus.
Mumps virus concentrated from the amniotic fluid of viral infected chick embryos contains about 7 per cent phosphatide, 60 per cent of which is sphingomyelin.
CHROMATOGRAPHIC STUDIES OF THE RHEUMATOID FACTOR
Authors: Lospalluto J. , Ziff M. 
Published: June 2004

Serum and serum fractions from patients with rheumatoid arthritis have been subjected to anion exchange chromatography on diethylaminoethyl cellulose. The rheumatoid factor activity was clearly separated from the bulk of the gamma globulin by virtue of the anomalous behavior of macroglobulins on this column.
Purification of rheumatoid factor by precipitation with fraction II, resolution in 4 M urea, and two successive fractionations on an anion exchanger yielded a highly active preparation consisting of approximately 95 per cent 19S gamma globulin with no detectable amount of 7S contaminant.
Evidence was obtained for the existence of two factors by cation exchange chromatography (carboxymethyl cellulose) of rheumatoid serum and of macroglobulin previously separated by anion exchange chromatography. One factor (factor I) agglutinated sensitized sheep cells and latex particles and also precipitated with human fraction II. The second (factor II) agglutinated latex partides and precipitated with fraction II but did not agglutinate sensitized sheep cells.
A substance with the properties of factor II was demonstrated in two of four normal sera by cation exchange chromatography. It was suggested that the agglutination of latex particles and precipitation with human fraction II, observed in the case of certain abnormal sera, may be due to elevated concentrations of factor II.
THE STREPTOKINASE-PLASMINOGEN SYSTEM
Authors: Krasner Robert I. , Young Genevieve 
Published: June 2004

Human plasminogen, plasma, or serum increased the pathogenicity of six streptokinase-positive streptococcal strains for mice. Combinations of commercial streptokinase and plasminogen or streptokinase and plasma did not usually increase mouse mortality to a greater degree than did plasminogen or plasma alone, suggesting that the maximal effective amount of streptokinase was produced by the organisms.
The pathogenicity of Salmonella paratyphi (fibrinolysin variable) and a Group D streptococcus (streptokinase-negative) was not increased by plasminogen, plasma, or streptokinase, whereas a combination of streptokinase and plasminogen, or streptokinase and plasma did significantly increase mouse mortality resulting from these organisms.
Combinations of certain concentrations of streptokinase and plasminogen increased the pathogenicity of a fibrinolysin-negative staphylococcal strain for mice to a greater extent than did either substance alone.
The observed results provide evidence that streptokinase, by an interaction with plasminogen, contributes to the pathogenicity of streptokinase-positive streptococci.
INVESTIGATIONS CONCERNING THE CHANGES IN SERUM PROTEINS DURING IMMUNIZATION
Authors: Bjørneboe M. , Schwartz Michael 
Published: June 2004

On hyperimmunization of rabbits with pneumococcal vaccine, increase in the content of gamma globulin and fall of albumin in the serum are produced. In such hyperimmunized rabbits, investigations of the plasma volume, albumin degradation, and the distribution of the albumin intra- and extravascularly were undertaken by Sterling's method employing rabbit albumin labelled with I131.
The investigations do not suggest any significant alteration in the albumin degradation nor in the distribution between the intra- and extravascular albumin. It was demonstrated that the plasma volume increases simultaneously with increase in the gamma globulin and fall in albumin.
It is concluded that the fall in serum albumin observed is due to a regulative mechanism which attempts to maintain the colloid-osmotic pressure by increasing the plasma volume.
INTERACTIONS BETWEEN RABBIT POLYMORPHONUCLEAR LEUCOCYTES AND STAPHYLOCOCCI
Authors: Cohn Zanvil A. , Morse Stephen I. 
Published: June 2004

A method has been described for the study in vitro of leucocyte-bacteria interactions which permits the simultaneous evaluation of both phagocytosis and intracellular bacterial inactivation. Employing this technique, the fate and localization of staphylococci in homogeneous suspensions of rabbit polymorphonuclear leucocytes have been studied.
Coagulase-positive strains of S. aureus were not efficiently ingested in the presence of normal rabbit serum. In contrast, coagulase-negative strains of S. albus were rapidly engulfed and inactivated.
Immune sera prepared against a coagulase-positive strain enhanced the the ingestion of the homologous organism as well as of three heterologous strains of S. aureus. Following phagocytosis, prompt intracellular killing of S. aureus occurred. The thermostable opsonins in immune sera reacted only with strains of S. aureus.
A comparison between polymorphonuclear leucocytes obtained from normal and immune animals revealed no differences in their ability either to ingest or kill coagulase-positive staphylococci.
Studies with other bacterial species are presented to illustrate: (a) phagocytosis followed by intracellular inactivation; (b) phagocytosis followed by intracellular survival; and (c) the absence of phagocytosis.
STUDIES ON PERSISTENT INFECTIONS OF TISSUE CULTURES
Authors: Henle Werner , Henle Gertrude , Deinhardt Friedrich , Bergs Victor V. 
Published: June 2004

In previous reports of this series, it was shown that persistent infection of MCN cultures with certain myxoviruses rendered the cells insusceptible to superinfection by several cytopathogenic viruses. It was thought that production of an interferon might be the cause of this resistance and efforts to confirm this suggestion have been presented.
Addition of ultraviolet-inactivated myxoviruses (mumps, Newcastle disease, influenza A, and Sendai) to MCN cultures for periods of 2 to 3 hours, followed by washing and refeeding of the cells, led to the subsequent release into the media of a substance which induced in fresh MCN cells a transitory resistance to infection by vesicular stomatitis virus, and prevented incomplete reproductive cycles of influenza A and Sendai viruses. Media containing this substance were free of detectable hemagglutinating activity and viral complement-fixing antigens. The substance was not neutralized by specific antiviral sera; it was not sedimentable by high speed centrifugation; it was not adsorbed onto red cells; but it was inactivated by trypsin. Thus, its properties matched those of the interferon described by Isaacs and his associates.
A comparison of the extent of resistance induced in MCN cells by decreasing doses of ultraviolet-inactivated myxoviruses (interference test) and the protection afforded by the media removed from the cultures prior to challenge and transferred to fresh MCN tubes (interferon test) revealed that wherever interference became detectable in the cells, the media of the corresponding cultures contained some interferon.
Interferon was obtained by inactivated myxoviruses also from primary cell cultures by the same techniques, but not from HeLa cells. Interferons derived from one type of culture may protect others equally well or show a certain degree of host specificity in that resistance in homologous cells may be somewhat more pronounced than in heterologous cultures. No resistance could be induced in HeLa cells by the interferon preparations employed.
Interferon was detected also in MCN cultures, persistently infected with mumps virus. Its concentration was apparently too small in carrier cultures maintained as routine to be measurable. However, when the cells were grown in heavy sheets in roller bottles, and especially when the volume of medium was reduced for several days prior to harvest, interferon became readily detectable.
These results strengthen the suggestion that interferon may play a decisive role in the establishment and maintenance of persistent infections in the system under study. Its nature, source, mode of action, and exact role in persistent infection remains to be elucidated.
EFFECT OF ANTIBODY AND COMPLEMENT ON PERMEABILITY CONTROL IN ASCITES TUMOR CELLS AND ERYTHROCYTES
Authors: Green H. , Barrow P. , Goldberg B. 
Published: June 2004

Rabbit antibody + complement alters the permeability properties of mouse Krebs ascites tumor cells and erythrocytes. When antibody + C' acts on ascites tumor cells in a low protein medium, intracellular K+ is lost from the cells at a rate far greater than the normal leak rate. At the same time the cells lose amino acids and ribonucleotides and become fully permeable to the Na+ of the medium. When antibody + C' acts in a low protein medium, the cells swell extensively and lose most of their macromolecules to the medium (hemoglobin from erythrocytes, protein and RNA from the ascites tumor cells). If the antibody + C' acts in a medium containing protein in sufficient concentration to balance the colloid osmotic pressure of the cells, the swelling is prevented; no macromolecules are then lost from the cells, but the loss of K+ and entrance of Na+ are not altered, and the loss of amino acids and ribonucleotides is only slightly affected.
It therefore appears that the action of antibody + C' is to produce functional "holes" in the animal cell membrane which permit the equilibration of cations and small molecules between cell and medium. This leads to an increase in the osmotic pressure of the cell and a rapid influx of water. The cell membrane and its "holes" are thereby stretched, permitting macromolecules to escape from the cell.
THE DEVELOPMENT OF THE ACUTE INFLAMMATORY RESPONSE TO EXPERIMENTAL CUTANEOUS MUCORMYCOSIS IN NORMAL AND DIABETIC RABBITS
Authors: Sheldon Walter H. , Bauer Heinz 
Published: June 2004

The histologic changes associated with the development of the acute inflammatory response to experimental cutaneous mucormycosis were studied at various times from 5 minutes to 24 hours after inoculation into normal rabbits and in rabbits with acute alloxan diabetes and acidosis. In normal animals the response by polymorphonuclear leukocytes began within a few minutes after inoculation, increased rapidly in extent and intensity and reached its peak within 6 to 12 hours. By that time there was also early proliferation of fibroblasts and of large mononuclear cells and these cellular reactions, together with the accumulated granulocytes, began to produce a demarcation of the lesions. Beginning 4 to 6 hours after inoculation the fungus showed some growth but this remained confined to the necrotic center of the lesions. In the diabetic rabbits the onset of the response by polymorphonuclear leukocytes was delayed by several hours, reduced in intensity and was apparently less effective. There was no proliferation of fibroblasts and the lesions were spreading rather than circumscribed. Fungus growth in the tissues began shortly after inoculation, was marked, progressed rapidly, and soon extended beyond the site of inoculation. The large mononuclear cells, however, appeared at about the same time and in equal number in the lesions of both diabetic and non-diabetic animals and showed no morphologic changes.
It is concluded that a significant delay and impaired effectiveness of the response by polymorphonuclear leukocytes, a lack of fibroblastic proliferation and an enhanced growth of the fungus lower host resistance to infection with it and are directly consequent on severe alterations in host metabolism.