bluuebunny/crossref_metadata_2025_split huggingface dataset:
A STUDY OF HEMOSIDEROSIS WITH THE AID OF ELECTRON MICROSCOPY
Authors: Richter Goetz W. 
Published: June 2004

Hemosiderin deposits in rats and in man were studied and compared by means of electron and light microscopy. Typical, isotropic, iron-positive hemosiderin granules were found to contain innumerable, closely packed, electron-dense particles, embedded in matter that was much less dense to electrons. Similar dense particles were often scattered diffusely through the cytoplasmic matrix of cells containing hemosiderin granules.
In cells of proximal convoluted tubules of rats given repeated intraperitoneal injections of hemoglobin the hemosiderin granules contained dense particles with a mean diameter of 55 A, and with a size-frequency distribution that indicated uniformity. These particles corresponded in size to the iron micelles of ferritin molecules. There was less uniformity of particles in hemosiderin granules situated in liver and reticulo-endothelial cells of rats that had been given a diet containing ethionine.
The dense aggregates representing hemosiderin granules were often situated inside discrete cytoplasmic organelles that were bordered by membranes, and sometimes contained "cristae"; and often the membranous borders were markedly disrupted. The term "sidersomes" is proposed for these specialized cytoplasmic structures which may be derivatives of mitochondria, and apparently play a part in the formation of hemosiderin.
Ferritin was crystallized from the livers and kidneys of the hemosiderotic rats with ease, but could not be crystallized from comparable quantities of liver and kidney tissue of untreated control rats.
Specimens from the liver and spleen of a patient with advanced hemosiderosis, obtained at an operation, were also studied. In liver and reticulo-endothelial cells many particles with diameters of about 60 A were scattered through the cytoplasmic matrix. By contrast, hemosiderin granules in the same cells contained particles that varied considerably in size. In representative granules, examined at high resolution, the size-frequency distribution of particle diameters displayed a periodicity consistent with the presence of small, uniform subunits. Electron micrographs of ferritin, isolated from the spleen of the same patient, provided confirmation for the inferences that the dense particles observed inside cells are iron micelles, and that ferritin is probably a component of hemosiderin.
THE NUCLEIC ACIDS OF T2, T4, AND T6 BACTERIOPHAGES
Authors: Jesaitis Margeris A. 
Published: June 2004

The deoxyribonucleic acids of the wild type strains of the T2, T4, and T6 bacteriophages have been shown to contain glucose as an integral part of the molecule; the amount of hexose present in each nucleic acid differs.
A study of the acid degradation products of the three nucleic acids has revealed that in each instance glucose is linked to the apurinic acid component.
In the case of the T6 nucleic acid it was found that two molecules of glucose are linked to hydroxymethylcytidylic acid. The other mononucleotides contained no glucose.
From the results which have been presented here, and from data presented by others, it can be concluded that the three viral nucleic acids differ in that they contain different proportions of free and glucose-substituted hydroxymethylcytidylic acids.
TRANSFORMATION REACTIONS BETWEEN PNEUMOCOCCUS AND THREE STRAINS OF STREPTOCOCCI
Authors: Bracco Richard M. , Krauss Marjorie R. , Roe Amy S. , MacLeod Colin M. 
Published: June 2004

Reciprocal transformation reactions to streptomycin resistance have been demonstrated between pneumococcus and 2 strains of viridans streptococci, which by the usual bacteriological criteria are distantly related to pneumococcus.
Desoxyribonucleic acid (DNA) extracts of a strain of streptomycin-resistant Streptococcus salivarius have been found capable of transforming pneumococcus and two strains of viridans streptococci but the strain itself was not transformed by autologous or heterologous DNA extracts.
The two strains of viridans streptococci were more efficient than pneumococcus as receptors of both autologous and heterologous transforming principles. It is inferred, therefore, that efficiency of transformation does not necessarily indicate closeness of relationship among bacteria.
The efficiency of transforming principles (TP's) from three streptococcal strains to induce streptomycin resistance in pneumococcus increased following their reduplication in pneumococcus. At the same time the efficiency of two of these TP's to transform streptococcus was reduced.
Resistance to optochin (ethylhydrocupreine), a characteristic of most streptococci, can be transferred to pneumococcus, a naturally susceptible species, by transformation reactions.
IMMUNOLOGIC STUDIES OF HUMAN HIGH DENSITY LIPOPROTEINS
Authors: DeLalla Louis , Levine Lawrence , Brown Ray K. 
Published: June 2004

High density serum lipoprotein underwent serologic and physicochemical alterations on aging during storage at 0°C. for 1 month, as judged by decrease of diffusion coefficient and increase of C' fixation. Ultracentrifugation, dialysis, and high concentrations of sodium chloride did not cause these changes. A protein sedimenting at density 1.24 in the ultracentrifuge reacted with antiserum to high density lipoprotein. Probably it was the protein portion of α lipoprotein dissociated from the lipide during ultracentrifugation.
Although the antiserum to high density lipoprotein did not react with low density lipoprotein prepared from normal serum, it reacted with similarly prepared lipoproteins from the serum of a patient with biliary cirrhosis.
LONG CHAIN FORMATION BY STRAINS OF GROUP A STREPTOCOCCI IN THE PRESENCE OF HOMOLOGOUS ANTISERUM: A TYPE-SPECIFIC REACTION
Authors: Stollerman Gene H. , Ekstedt Richard 
Published: June 2004

Strains of group A streptococci, types 30 and 12, were observed to grow in extremely long chains in liquid media to which homologous antiserum was added. Addition to the media of antisera to heterologous types of streptococci failed to produce long chain growth. The long chain effect was destroyed by absorption of the antiserum with organisms of homologous type but was unaffected by absorption with organisms of heterologous types.
The reaction disappeared at concentrations of antisera smaller than 0.25 per cent and was independent of complement or other heat-labile serum factors. Addition of trypsin to the culture to remove M protein from cells prevented long chain formation. The long chain effect depended upon the constant presence of antibody to the media. In its absence, the organisms promptly reverted to short chain growth.
The phenomenon appears to have general applicability to those strains rich in M protein with only an occasional strain not responding as described. Further studies are in progress to determine the cause of this atypical response. The applicability of this phenomenon in detecting type-specific antibody using indicator strains of a variety of streptococcal types is discussed.
STUDIES ON BACTERIOPHAGES OF HEMOLYTIC STREPTOCOCCI
Authors: Krause Richard M. 
Published: June 2004

The host ranges of bacteriophages for group A, types 1, 6, 12, and 25 and group C streptococci have been determined. The findings indicate that the susceptibility to these phages is primarily a group-specific phenomenon, although it is modified by several factors such as the hyaluronic acid capsule, lysogeny, and possibly the presence of surface proteins. Phage antibody studies indicate that while the group A phages are antigenically related, they are distinct from the group C phage. This is in agreement with the observation that group A phages are not specific for their homologous streptococcal types.
The purified group C carbohydrate inactivates group C phage but not the group A phages, thus suggesting that the carbohydrate, a component of the cell wall, may serve as the phage receptor site. It has not been possible to inactivate the group A phages with group A carbohydrate.
Phage lysis of groups A and C streptococci is accompanied by fragmentation of the cell wall since the C carbohydrate has been identified serologically and chemically in the supernate of centrifuged lysates. The immediate lysis of groups A and C hemolytic streptococci and their isolated cell walls by an accesory heat-labile lytic factor in fresh group C lysates is also described.
THE RELATIONSHIP BETWEEN THE VASCULAR MANIFESTATIONS OF SHOCK PRODUCED BY ENDOTOXIN, TRAUMA, AND HEMORRHAGE
Authors: Zweifach Benjamin W. , Thomas Lewis ,   With the Technical Assistance of P. Viera and C. Mikros
Published: June 2004

The vascular effects of lethal doses of E. coli endotoxin, as observed in the mesentery of the rat, resemble the reactions of traumatic and hemorrhagic shock in the following respects: a profound inhibition of arteriolar and precapillary reactivity to topical epinephrine occurs after an initial stage of hyperreactivity; the small veins show failure to relax completely following constrictor doses of epinephrine; and the terminal vessels develop an unusual sensitivity to fluctuations in temperature of the fluid irrigating the tissue.
Rats in which tolerance to bacterial endotoxin is induced, by repeated doses given daily, become highly resistant to the lethal effects of both drum trauma and hemorrhagic shock.
However, rats in which the adaptation to traumatic shock is produced by repeated exposure to drum trauma, do not develop a significant degree of tolerance to lethal doses of endotoxin.
The injection of small non-lethal doses of bacterial endotoxin during non-lethal episodes of trauma or hemorrhage, leads to the development of irreversible shock and death.
The bearing of these findings on the problem of the relationship between endotoxin and traumatic shock is discussed.
STUDIES OF THE PLASMIN SYSTEM
Authors: Norman Philip S. 
Published: June 2004

A general assay method involving casein digestion is shown to be applicable for determination of several components of the plasmin system.
Total plasminogen of human serum can be measured by use of sufficient streptokinase for instantaneous activation, accompanied by protection of the active plasmin with casein.
Total plasminogen of guinea pig serum can be measured after complete activation with streptokinase in combination with human activator.
The activator principle in whole human serum can be measured by its ability to activate guinea pig plasminogen.
MACROGLOBULINEMIA
Authors: Korngold Leonhard , Van Leeuwen Gerda 
Published: June 2004

Highly purified pathological macroglobulins, which had been characterized electrophoretically and in the ultracentrifuge, were studied by the Ouchterlony gel diffusion technique.
These macroglobulins were shown to be antigenically related to normal γ1-macroglobulin (19S) as well as the 7S γ-globulins.
The pathological macroglobulins differ among each other and they are antigenically deficient when compared with the normal macroglobulin.
There is no correlation between the macroglobulin's antigenic structure and its physico-chemical properties.
THE RENAL LESIONS OF ELECTROLYTE IMBALANCE
Authors: Oliver Jean , MacDowell Muriel , Welt L. G. , Holliday M. A. , Hollander W. , Winters R. W. , Williams T. F. , Segar W. E. 
Published: June 2004

Renal tubular lesions during the early phases of progressive potassium depletion in rats were found in nephrons isolated by microdissection in two locations, the collecting tubules and the proximal convolutions. All other portions of the nephron, in particular the "distal tubule," i.e. ascending limbs of Henle's loop and distal convolutions, showed no structural alterations except the passive effects of dilatation and cellular compression which developed as a result of primary disturbances lower in the tubular system.
The alterations affected all the collecting tubules uniformly and took two forms; the more severe, a swelling and hyperplasia of the tubular epithelium and the lesser, an intracellular accumulation of granule droplets. The former was limited to the outer zone of the medulla, the latter to its inner zone. In the proximal convolution the structural alteration began in its middle third and extended downward towards the medulla; only occasional nephrons were affected.
The essential nature of the more severe epithelial lesion was similar in both collecting tubule and proximal convolution, beginning as a swelling of cell bodies, increasing to protoplasmic disturbances with disintegration of the mitochondrial pattern, followed by rupture of cells and nuclear disappearance. These retrogressive alterations were followed by prolific regenerative hyperplasia. In the collecting tubules of the outer zone these epithelial alterations were present in both the clear and the intercalcated cells; in the latter the swelling of the cells was not prominent, but the hyperplastic proliferative increase in their number was the predominating feature of the lesion when the dissected tubules were viewed intact in the continuity of their topographical relations.
The cellular alterations in the tubules are associated with an inability to concentrate the urine; reasons are given for considering this functional disturbance a correlate of the structural lesion in the collecting tubules.
GROWTH CHARACTERISTICS OF POLIOVIRUS IN HELA CELLS: NUCLEIC ACID METABOLISM
Authors: Maassab H. F. , Loh Philip C. , Ackermann W. Wilbur 
Published: June 2004

The RNA and DNA contents of the nucleus and cytoplasm of the HeLa cell were determined. The rates of incorporation of P32 into the various nucleic acid fractions were established for the ordinary HeLa cell maintained under a set of standard conditions.
The changes in the rates of incorporation of P32 and in the amounts of RNA and DNA which occurred subsequent to infection with poliovirus were followed throughout the infectious cycle. These changes were correlated with the intracellular appearance of the newly formed virus. A net synthesis of RNA occurred in the cytoplasmic component of the cell. The increase was detectable 2 hours before the first appearance of demonstrable virus and reached a maximum (2.5 times normal) at 6 hours. Viral increase was not maximal before the 7th hour after infection.
AN ELECTRON MICROSCOPE STUDY OF THE GLOMERULUS IN NEPHROSIS, GLOMERULONEPHRITIS, AND LUPUS ERYTHEMATOSUS
Authors: Farquhar Marilyn G. , Vernier Robert L. , Good Robert A. 
Published: June 2004

Renal biopsies from 16 patients with nephrosis, 7 patients with glomerulonephritis, and 3 patients with disseminated lupus erythematosus were studied with the electron microscope.
The observations presented indicate that early in the course of each of these diseases alterations occur in the fine structure of the glomeruli which serve to distinguish one disease process from another.
In nephrosis, some distortion of the organization of the epithelial foot processes was seen in all patients. These epithelial changes constituted the early, consistent lesion of the disease. There was frequently also a swelling of the endothelium.
In glomerulonephritis, pronounced proliferative changes involving the endothelium and to a lesser extent the epithelium, together with the laying down of a basement membrane-like material, represented the predominate pathologic processes. There was also a swelling of both endothelial and epithelial cytoplasm. The epithelial foot processes generally appeared normal.
In patients with a clinically "mixed" picture of nephrosis and nephritis, the glomerular changes were likewise "mixed," for various combinations of epithelial, endothelial, and basement membrane abnormalities were present.
In disseminated lupus erythematosus, a more or less generalized thickening of the basement membrane proper associated with a variable degree of endothelial proliferation was seen. It is suggested that an accentuation of the process of basement membrane thickening results in the "wire loop" appearance sometimes seen by light microscopy.
Although the earliest alterations in glomerular fine structure were characteristic for each of the disease processes, at later stages the changes were not always distinctive. The resulting scarred or "hyalinized" glomeruli, composed of relatively homogeneous, basement membrane-like material, and a few atrophic cells, appeared quite similar.
Although the functional implications of the structural changes observed remain obscure at this time, it is believed that insight into mechanisms may stem from such observations.
POLIOVIRUS PRECIPITINS
Authors: Le Bouvier George L. 
Published: June 2004

Antigens present in poliovirus concentrates react with antibodies present in the serum of hyperimmunized monkeys to give type-specific precipitates. One or more bands of precipitate can be formed wherever such homotypic reactants, diffusing into an agar gel, meet in sufficient concentration and in equivalent proportions.
No qualitative differences have been detected between the type-specific reactions given by different strains of the same virus type; and no precipitates have been seen which could be called "group-specific." Non-specific precipitates have occasionally been observed.
Type-specific poliovirus precipitins are found in the serum of poliomyelitis patients. Their concentration has been measured by a standardized method. They tend to develop in parallel with neutralizing antibodies against the same virus type, increasing in amount during the first weeks of illness in those patients who show concurrent neutralizing antibody rises.
The precipitation reaction has proved valuable in the antigenic analysis of polioviruses. Its general adoption as a diagnostic procedure is perhaps unlikely; but it may be well worth applying for special purposes.
THE INFECTION OF CHIMPANZEES WITH ECHO VIRUSES
Authors: Itoh Heihachi , Melnick Joseph L. 
Published: June 2004

The oral and parenteral infections of chimpanzees receiving echo Types 6 and 4 viruses successively are described. The two infections, spaced 2½ months apart, and given by the same route in each animal, failed to induce overt disease. The inapparent infections were demonstrated by virus excretion in the throat and the stools and the development of neutralizing antibodies. Complement-fixing antibodies also appeared after Type 6 infection, but fell more rapidly than the neutralizing antibodies.
After oral infection, echo-6 virus was found for equal periods in both the throat and feces, but echo-4 persisted in the throat for much longer periods than in the lower bowel. Almost no virus carriage occurred after parenteral inoculation. No true viremia was exhibited in any of the animals.
One of the chimpanzees had neutralizing antibodies against Type 6 virus in its pre-inoculation serum. It responded extraordinarily to the Type 6 exposure, developing antibody levels of 1:50,000 to echo-6, of 1:1024 against the echo-6' variant, and of 1:64 against the echo 6'' variant.
Although Type 4 antibodies developed after the exposure, they proved difficult to measure by ordinary methods. However, they could be satisfactorily assayed by the plaque reduction method.
Three other chimpanzees fed echo-2, echo-3, and an untypable echo virus, respectively, yielded results confirming those established with Types 4 and 6.
EFFECTS OF CELLULAR CONSTITUENTS OF MYCOBACTERIA ON THE RESISTANCE OF MICE TO HETEROLOGOUS INFECTIONS
Authors: Dubos René J. , Schaedler Russell W. 
Published: June 2004

Vaccination with living attenuated tubercle bacilli (BCG) was found to increase the resistance of mice to infection with virulent staphylococci.
An even more striking protective effect could be elicited by intraperitoneal or subcutaneous injection of small amounts (0.1 mg. or more) of killed BCG cells.
The killed BCG cells retained most of their protective activity after prolonged heating at acid, neutral, or basic reactions—and after extraction with acetone, methanol, and NaOH (at pH 10.5). Some protective activity could be recovered in a fraction soluble in methanol at 55°C.
The protective effect against infection manifested itself in a prolongation of survival time following infection, and also in the fact that smaller numbers of staphylococci were recovered from the organs of infected mice. Both types of effects were still evident 10 weeks after vaccination.
Injection by the intraperitoneal route of killed cells of BCG, or of methanol extracts of them, elicited in mice a high level of protection against intravenous injection of Myco. fortuitum.
A protective effect quantitatively and qualitatively similar to that elicited by BCG, resulted from the intraperitoneal or subcutaneous injection of killed cells of Myco. fortuitum.
EFFECTS OF CELLULAR CONSTITUENTS OF MYCOBACTERIA ON THE RESISTANCE OF MICE TO HETEROLOGOUS INFECTIONS
Authors: Schaedler Russell W. , Dubos René J. 
Published: June 2004

Injection of certain cellular constituents of mycobacteria into mice simultaneously with, or shortly after, infection with Staph. aureus or with Myco. fortuitum, markedly shortened the life of the infected animals. This infection-enhancing effect could be achieved by injecting the cellular constituents by either the intravenous, the intraperitoneal, or the subcutaneous route.
Suspensions of killed mycobacteria were injected into mice which had been infected several months before with small doses of various bacterial pathogens and which still harbored small numbers of living organisms in their organs. Under these conditions, a marked increase in the numbers of living bacteria in the organs of the treated mice could be detected within a very few days after treatment with the mycobacterial products, and a certain percentage of the animals died rapidly.
One of the first and most constant manifestations of the change in the infectious process from the chronic to the acute state was the appearance of a large microbial population in the liver. This happened even though Staph. aureus and Myco. fortuitum are rapidly cleared from the liver of normal mice.
In addition to killed cells of BCG and of Myco. fortuitum, pertussis vaccine and the purified lipopolysaccharide (endotoxin) of Gram-negative bacilli also proved capable of converting chronic bacterial infections into acute infectious processes.
INTERRELATIONSHIPS BETWEEN EXPERIMENTAL HYPERCHOLESTEREMIA, MAGNESIUM REQUIREMENT, AND EXPERIMENTAL ATHEROSCLEROSIS
Authors: Vitale J. J. , White P. L. , Nakamura M. , Hegsted D. M. , Zamcheck N. , Hellerstein E. E. ,   With the Technical Assistance of P. Connors, A. Gotsis, and T. Faherty
Published: June 2004

The addition of cholesterol and cholic acid to a diet containing 24 mg. percent of magnesium, an amount normally required for young rats, resulted in magnesium deficiency in rats. This was characterized by hyperexcitability, hyperemia of the ears, calcium deposition in the kidney tubules, low serum magnesium levels, and decreased oxidative phosphorylation of heart mitochondria. All these lesions were prevented by raising the dietary magnesium level four to eight times.
Feeding the atherogenic diet produced the deposition of lipide in the aorta and in the heart valves. The extent of this intimal sudanophilia was reduced by large amounts of dietary magnesium although serum cholesterol values did not fall and usually rose. This represents perhaps the first clear cut disassociation between serum cholesterol values and the extent of intimal sudanophilia.
Raising the level of dietary protein from 10 to 20 per cent decreased the serum cholesterol levels and the extent of the kidney lesions. Thyroxine administration lowered the serum cholesterol values, abolished the kidney lesions and reduced the intimal sudanophilia. These effects occurred even though the serum magnesium levels remained low.