[Respiratory function at rest in obese children (author's transl)].

Abnormalities of the respiratory function are a common finding in adult obesity. In order to investigate the occurrence of similar facts in pediatric age, a group of 39 obese children (20 girls and 19 boys, aged from 7 to 15 years) whose weight excess for their height ranged from 25 to 105 p. 100 was studied and compared to a control group of normal children of similar ages. Lung volumes, blood gases, transfer factor of the lung for CO, dynamic lung compliance, total lung resistance and ventilatory response to CO2 have been studied. In these obese children by contrast to obese adults, the vital capacity and the residual volume were normal. The blood gases, the transfer factor for CO, the dynamic lung compliance and the total resistances of the lung were similar to those of the normal group. The respiratory patterns were normal in all children but one who had during a short time a periodic ventilation with short periods of breath-holding. The ventilatory response to CO2 of the obese children was decreased and a highly significant correlation was found between the individual values of the respiratory response to CO2 and the percentage of weight excess. Different hypotheses are discussed to explain these results.


Enzymatic histamine degradation by human skin.

1. Degradation of histamine by homogenized human skin in vitro, in the presence of the cofactor S-adenosyl methionine, indicates the presence of the histamine metabolizing enzyme histamine-N-methyl transferase in human skin. Under the experimental conditions described, no significant histamine degradation by diamine oxidase was observed. 2. The enzyme activity is temperature-sensitive with an optimum at 37 degrees C. The enzyme is stable in in intact excised skin at -20 degrees C, but unstable in homogenized skin at this temperature. 3. Little or no enzyme activity is present in mid- or deep dermis, but the distribution of the enzyme between superficial papillary dermis and epidermis is uncertain. 4. The presence of a potent histamine degrading mechanism raises the possibility that histamine-N-methyl transferase activity may be an important modulating factor in histamine-mediated skin disorders.


The effect of diuretics on the faecal excretion of water and electrolytes in horses.

1. The effect on plasma, urinary and faecal electrolytes of frusemide and hydrochlorthiazide was measured in ponies, mean weight 180 kg. 2. The rapid loss in urine of large quantities of sodium had only a small effect on plasma sodium concentration. 3. Faecal sodium excretion was increased substantially after the administration of frusemide. 4. Frusemide increased faecal potassium during the 48 h following administration and faecal water in the 24/48 h period. It also produced a hypopotassaemia. 5. Hydrochlorthiazide increased faecal chloride during the 24 h after administration. 6. Frusemide increased the intestinal transit time of both liquid (polyethylene glycol) and particulate (Cr2O3) markers.


The effects of ether stress and betamethasone treatment on the concentrations of noradrenaline and dopamine in various regions of the rat brain.

1. The effects of ether stress on noradrenaline (NA) and dopamine levels in different regions of the rat brain were studied. 2. Exposure to ether vapour (90 s) caused a significant decrease in the concentration of hypothalamic NA but had no effect on catecholamine (CA) concentrations in the other regions studied. 3. Treatment with betamethasone alone (20 microgram/ml) given in the drinking water for 24 h, had no effect on CA levels in the cerebral cortex, midbrain or hypothalamus. However, pretreatment with this dose of steroid prevented the decreases in hypothalamic NA which were normally seen after ether stress and also induced significant increases in the concentration of midbrain NA. 4. The data provide further support for the involvement of NA in the regulation stress-induced corticotrophin (ACTH) release and indicate that centres other than the hypothalamus may be involved in mediating the inhibitory action of betamethasone on the response to ether stress.


The effect of zinc on anaphylaxis in vivo in the guinea-pig.

The protective effects of pretreatment with zinc sulphate aerosols against bronchoconstriction induced by egg albumen or histamine aerosols were assessed in sensitized or non-sensitized guinea-pigs respectively. Pretreatment with an adequate concentration of zinc sulphate aerosol significantly prolonged the time of onset of bronchoconstriction in sensitized guinea-pigs challenged with egg albumen, but did not appreciably alter the onset time of histamine-induced bronchoconstriction in non-sensitized animals. These findings suggest that zinc aerosols may be of prophylactic value against bronchoconstriction of allergic origin.


Carbon dioxide output and elimination in children under anaesthesia.

The requirements for fresh gas inflow with the Bain breathing circuit in children was examined by determining the PaCO2 in 46 children during controlled ventilation with a total fresh gas inflow of 3.5 l/min and by measuring the carbon dioxide output in 83 children under anaesthesia. It could be shown that all children below 40 kg body weight had a PaCO2 below 40 torr (5.32 kPa) and the PaCO2 paralleled the body weight, i.e., the lowest carbon dioxide tension was seen in children under 10 kg. As expected, the highest carbon dioxide output was found in children below 5 kg body weight; the carbon dioxide output per kilogram decreased with increasing body weight up to 30-35 kg and remained at that level in larger children. Children in their teens, although they may have attained adult body weight, had a higher carbon dioxide output than adults. Based on these findings, our recommendation of a total fresh gas inflow of 3.5 1/min for all children would appear adequate for a body weight up to 35 kg on controlled ventilation. In children under 10 kg body weight, a reduction of the total fresh gas flow to two litres per minute will avoid marked respiratory alkalosis. For children over 35 kg, a fresh gas flow of 100 ml/kg/min should be satisfactory during controlled ventilation.


Reduction of hypoxic pulmonary vasoconstriction by nitrous oxide administration in the isolated perfused cat lung.

Local pulmonary vasconstriction in response to alveolar hypoxia is a protective mechanism reducing blood flow to poorly oxygenated areas of lung. Pulmonary blood flow is thereby directed to better oxygenated lung units and venous admixture and the resulting arterial hypoxaemia is reduced. The effect of nitrous oxide on the pulmonary pressor response to alveolar hypoxia was assessed in the isolated perfused cat lung preparation under conditions of constant flow and constant left atrial and airway pressures. Nitrous oxide, in concentrations of 50 per cent and 75 per cent, was found to produce a reversible depression of the hypoxic pulmonary pressor response. The importance of hypoxia pulmonary vasconstriction and the possible implications of its reduction by anaesthetic agents are discussed.


Meperidine and morphine as intravenous surgical premedicants.

Morphine 5 mg and 10 mg and meperidine 50 mg and 100 mg were studied as intravenous surgical premedicants in 160 patients. Relief of anxiety, sedation, lack of recall and side effects were the variables evaluated. Neither morphine nor meperidine proved to be particularly good surgical premedicants. There appeared to be no significant differences between the two drugs, but what differences there were tended to favor meperidine.


The effects of etomidate on arterial pressure, pulse rate and preganglionic sympathetic activity in cats.

We have studied the effects of etomidate on preganglionic cervical sympathetic activity, arterial pressure, and pulse rate. Normal and baroreceptor-denervated animals were studied. On the basis of findings it is concluded that etomidate exerts a minimal direct depressant action on the cardiovascular system. A profound depression of sympathetic tone was observed in spite of unaffected arterial pressure. Etomidate was also shown to possess a mild vagolytic action.


Maternal and neonatal effects of methoxyflurane, nitrous oxide and lumbar epidural anaesthesia for Caesarean section.

General anaesthetic techniques continue to be used for Caesarean section despite the possible increased incidence of foetal acidosis and neonatal depression. Two techniques of general anaesthesia (methoxyflurane-oxygen and nitrous oxide-oxygen) and lumbar epidural anaesthesia were compared in 37 patients under-going elective Caesarean section. Apgar scores at birth were similar in all three groups. Neurophysiological testing of the neonates at six hours and twenty-four hours of age revealed a superiority for the methoxyflurane-oxygen and lumbar epidural techniques, although the babies in the epidural group tended to be hypotonic. Cord blood gas analysis showed the babies in the methoxyflurane group to have a higher PaO2 with less metabolic acidosis than the babies from the other two groups. The maternal effects of the three anaesthetic techniques were similar, with only a small rise in serum fluroide levels noted in the methoxyflurane group.


Sympathetic blockade of isolated limbs by intravenous guanethidine.

As a result of experience at the Montreal General Hospital, it has been found that intravenous guanethidine blockade of extremities has therapeutic, prophylactic and diagnostic value in conditions where the aetiology is a disorder of sympathetic nervous conduction. The properties of guanethidine, namely its selective action on blocking the sympathetic nervous system peripherally, together with its long half time and rapid tissue fixation, render it a very useful drug in techniques where an isolated limb is blocked with guanethidine. Experience on a 18-month basis suggests that the procedure of intravenous guanethidine blockade offers exceptionally good results for a non-invasive technique. Work is now in progress to study the possible use of guanethidine in the treatment of phantom limb pain, and also to see whether other drugs, such as thymoxamine, could be used in a similar fashion to guanethidine.


A trial of enflurane for paediatric out-patient anaesthesia.

Enflurane was compared with halothane for anaesthesia for short surgical procedures in paediatric out-patients. Induction of anaesthesia was more prolonged with enflurane and recovery times were similar with both agents. Coughing and laryngospasm during induction occurred more frequently with enflurane. The incidence of post-operative complications was essentially similar in both groups, but there was no evidence that the use of enflurane was followed by rapid recovery at home. Enflurane has no advantages over halothane in anaesthesia for short procedures for paediatric out-patients.


Recovery from anaesthesia in outpatients: a comparison of narcotic and inhalational techniques.

Forty-one patients undergoing outpatient anaesthesia and operation were studied. Nineteen received inhalation agents. Twenty-two received narcotics. Up to one hour post-operatively, patients who received inhalation anaesthesia performed significantly better than did those who received narcotics. After 60 minutes there was no significant difference between the two groups. It is suggested that narcotics be avoided in patients who will be discharged within one hour of anaesthesia. A small number of patients exhibited slow recovery. It is suggested that these may be patients at risk and that special care be exercised.


The mode of action of homocysteine on mouse brain glutamic decarboxylase and gamma-aminobutyrate aminotransferase.

In the belief that homocysteine-induced convulsions might be related to alterations in brain gamma-aminobutyric acid metabolism, we have studied the action of this amino acid on the activity of glutamic decarboxylase (GAD, EC 4.1.1.15) and gamma-aminobutyrate aminotransferase (EC 2.6.1.19) of mouse brain in vitro DL-homocysteine competitively inhibited GAD with respect to both L-glutamate and pyridoxal 5'-phosphate. The respective Ki's were 3.8 mM and 0.3 mM. The activity of GABA-T also was altered in the presence of DL-homocysteine. A competitive inhibition (Ki = 6 mM) was observed with gamma-aminobutyric acid, and an uncompetitive inhibition with respect to pyridoxal 5'-phosphate and alpha-ketoglutarate. These results are explained in terms of a dual action of homocysteine on each of the enzymes: one involving a competition for substrate binding site and the other involving the formation of an inactive inhibitor-cofactor complex. The significance of the inhibition of these enzymes of gamma-aminobutyric acid metabolism is discussed in relation to the convulsant action of homocysteine.


Isolation and partial characterization of a protein synthesis inhibitor from brine shrimp embryos.

Encysted embryos of the brine shrimp, Artemia salina, contain an inhibitor of protein synthesis that appears to be important in translational control. In cyst homogenates, the inhibitor appears to be partitioned almost equally between the cytosol and ribosome fractions and it has been purified from both fractions to near homogeneity. In a cell-free protein-synthesizing system derived from Artemia cysts, with poly(U) as messenger, the protein inhibits polyphenylalanine synthesis proportional to inhibitor concentration up to about 75% inhibition, and the primary site of action appears to be at the elongation step. The inhibitor activity is not altered by 50-150 mM KCl in the reaction mixture, but it is slightly more effective at 5 mM MgCl2 than at 10 mM MgCl2. The inhibitor is a heat-labile protein of 130000 molecular weight and is devoid of hydrolase activity. Our data indicate that the inhibitor is not elongation factor EF-1 or EF-2, but we are studying the possibility that it may be a modified form of elongation factor EF-2.


Apparent saturability of a 4S dihydrotestosterone-binding protein in rat muscle cytosol: role of 3 alpha-hydroxysteroid dehydrogenase and albumin.

In our studies of the binding of steroids in rat skeletal muscles, we have shown the existence of a saturable '4S' dihydrotestosterone-binding protein of low affinity (Kd = 1.16 X 10(-6) M). Competition studies led us to believe that the binding of dihydrotesterone (DHT) was due to 3 alpha-hydroxysteroid dehydrogenase (3 alpha-OHSD) enzyme responsible for the conversion of DHT to androstanediol (Adiol). Indeed, both the binding and the enzymatic activity are inhibited by various 3-keto steroids. In addition, the dissociation constant (Kd) and the Michaelis constant (Km) of the enzyme are similar. However, experiments with ammonium sulfate fractions of the cytosol have shown a partial separation of the binding and of the enzymatic activity. On the other hand, we have established that DHT (3 micrometer) is almost completely metabolized to Adiol during a 2-h incubation of 0 degrees C even in the absence of added coenzymes. Furthermore the '4S' protein binds Adiol more strongly than DHT and this binding is not saturable. Finally the binding behaviour of both DHT and Adiol with either muscle cytosol or rat albumin is similar when subjected to ammonium sulfate fractionation and sucrose density gradient centrifugation. In conclusion, the skeletal muscle 3 alpha-OHSD rapidly metabolizes DHT into Adiol which then binds strongly to a nonspecific binding protein, presumably rat serum albumin. Thus it can be said that the observed saturability of DHT binding is only apparent.


The immune response of calves given Mycoplasma bovis antigens.

Seven calves seven to 30 days of age were given Mycoplasma bovis antigen by different routes. Immunization was in two phases. The first consisted of single or multiple SC, IV or oral doses of antigen for two to four weeks. The second phase consisted of multiple SC or ID injections given from the eighth to the 19th week. The experiment was terminated at 26 weeks. Antibody titers were followed by indirect hemagglutination, growth inhibition and tetrazolium reduction inhibition. Total serum protein, protein fractions and IgG and IgM concentrations were determined in serums of one calf and the distribution of indirect hemagglutination antibodies in IgG and IgM classes were determined in serums of two of the calves. Indirect hemagglutination titers of 1280 and peak titers of >20,480 occurred after the first and second phases respectively. There was no relationship between total serum IgG or IgM concentrations and indirect hemagglutination titers. In one calf given M. bovis antigen in one dose SC and five weekly doses IV in phase I, indirect hemagglutination antibodies appeared in IgM within one week and IgG by four weeks, IgG antibody activity rose steadily until the 17th week but declined at the 26th week, whereas IgM activity after the initial rise dropped at the 13th week but rose even higher as a result of second phase ID injections. Another calf given six weekly IV doses of M. bovis antigen in phase I developed indirect hemagglutination antibodies in IgM peaking at four weeks then declining but with no IgG response. Activity in both IgM and IgG occurred after the second phase. Growth inhibition antibodies were found only on two occasions in one calf serum and tetrazolium reduction inhibition activity when tested never gave titres exceeding 1:32.


Cytology of bovine foetal fluids.

Cell contents of foetal fluids obtained separately from amniotic and allantoic cavities of live cows by transvaginal amniocentesis and by aspiration from pregnant uteri immediately after slaughter were studied using Papanicolaou's staining procedure. The samples obtained belonged to cows which were between ten to 24 weeks of gestation. Cell scrapings from foetal and membranous surfaces normally in contact with the foetal fluids were also stained simultaneously with foetal fluid smears by Papanicolaou's method to determine the probable origin of the cells detected in the amniotic and allantoic cavities. The cell types were classified according to morphology and tinctorial patterns and their origin was deduced on the basis of similarity to cell scrapings from the surface layers of foetus and foetal cavities. The evaluation of foetal fluid cells revealed that a majority of cells are of foetal origin and that the cytological features of these cells may be useful in assessing the condition of the foetus.


Swine dysentery: inoculation of gnotobiotic pigs with Treponema hyodysenteriae and Vibrio coli and a Peptostreptococcus.

Pure cultures of Treponema hyodysenteriae given orally to conventional pigs resulted in the development of swine dysentery, whereas identical cultures given to gnotobiotic pigs did not produce the disease. Oral inoculation of gnotobiotic pigs with Vibrio coli and/or a peptostreptococcus in addition to T. hyodysenteriae did not result in dysentery. Neutralization of gastric secretions with NaHCO3 immediately prior to inoculation with T. hyodysenteriae increased the period during which treponemes were evident in the feces, as did the inoculation of this organism via the intracecal route. None of the gnotobiotic pigs with a persistent fecal Treponema population developed signs of dysentery. Factors other than those investigated in this work must play a part in the etiology of swine dysentery.


Cellular distribution of orally and intramuscularly administered iron dextran in newborn piglets.

Histochemical studies were performed on tissues from piglets of different ages treated orally with iron dextran soon after birth. The mucosal cells in the distal region of the small intestine were heavily laden with stainable iron granules during the first three days after the iron administration. The absorptive epithelial cells are desquamated within seven to ten days after birth. Consequently, the number of iron granules gradually diminishes during the first seven days after treatment and no iron granules are demonstrated 12 days after the administration of iron. The iron dextran complex is pinocytosed in newborn piglets and then transported via the lymphatic system. Thus the sinusoidal lining cells of the body and mesenteric lymph nodes are already heavily laden with iron granules 24 hours after oral treatment. This iron store is released only slowing during the first weeks of life. Great amounts of iron granules are demonstrated in the liver and spleen macrophages during the first week after the administration of iron. Due to the rapid utilization of iron in growing piglets these iron stores diminish sharply during the weeks following birth. The distribution of stainable iron in the lymph nodes, liver and spleen seven days after intramuscular injection of iron dextran in newborn piglets was comparable to that for oral administration at that stage of the experiment.


Studies on a canine intestinal spirochete. I. Its isolation, cultivation and ultrastructure.

The microscopic examination of colonic scrapings from 12 of 18 normal dogs revealed the presence of a spirochete. From two such dogs a spirochete was isolated and successfully cultured. Although similar in outward appearance to the porcine spirochete of swine dysentery the canine spirochete possessed ultrastructural properties which distinguished it from the porcine agent. This canine agent is thought to constitute a separate species and should not be confused with the agent associated with swine dysentery.


The pathogenesis of the lesions produced by Eimeria zuernii in calves.

The pathogenesis of the lesions caused by Eimeria zuernii in calves is described. The gross lesions and the development and resolution of the microscopic lesions of the large intestine are described in detail. The development of the first asexual generation causes few changes in the lower ileum. The second asexual generation and gametogony of E. zuernii appear to be the pathogenic stages of its development. It is during these stages of the life cycle that epithelium is lost, capillaries are exposed and that hemorrhage into the lumen of the large intestine occurs. Resolution of these lesions takes place in approximately ten days in calves which survivie.


Bovine reaginic antibody III. Cross-reaction of antihuman IgE and antibovine reaginic immunoglobulin antisera with sera from several species of mammals.

Using antisera specific for the heavy chain of human IgE and bovine reaginic immunoglobulin, the degree of cross-reaction amongst sera from pig, rat, rabbit, guinea pig, goat, cow, horse, dog, cat and human was tested. Antihuman IgE antiserum gave strong reactions with pig, rabbit, cow, goat and human sera (100% to 15.1%) and weak reactions with rat, guinea pig, horse, dog and cat sera (10.1% to 3.22%). Antibovine reagin antiserum produced a considerable amount of cross-reaction with sera from pig, rat, rabbit, goat, horse and human (43.6% to 20.1%) with limited reactions with guinea pig, dog and cat sera (13.9% to 9.3%).


Significance and pathogenic role of Mycoplasma arginini in cat diseases.

Eighty-one strans of Mycoplasma arginini were isolated from swabs and tissues cultured from a series of 555 cats. The majority of these strains (84%) were recovered from the oropharyngeal regions. M. arginini was experimentally inoculated into young kittens. No clinical disease was produced. However, there was rapid colonization in the inoculated sites.


[Characterization of telluric bacteria attributable to Pseudomonas maltophilia].

The taxonomic position of some telluric non-fermenting Gram-negative bacteria collected into a phenon representing about a quarter of the soil isolates by an earlier numerical analysis is specified. The Shapiro--Chargaff coefficient determined by thermal-transition curves of the DNA and their hybridization by nitrocellulose filters method show a close affinity with Pseudomonas maltophilia.


Enterotoxin B production by Staphylococcus aureus under controlled fatty acid nutrition induced by cerulenin.

Cells of Staphylococcus aureus, strain S-6, can grow in the presence of 100 microgram of cerulenin/ml if the basal medium is supplemented with certain saturated or unsaturated fatty acids. The production of enterotoxin B (SEB) is markedly influenced by both the ratio of saturated to unsaturated fatty acid and by the melting point of the unsaturated fatty acid supplement. The results presented suggest that a certain degree of membrane fluidity promotes maximum SEB production and that greater or lesser degrees of membrane fluidity prohibit substantial SEB formation but fail to affect final growth density.


The relationship between conidiation and alkaloid production in saprophytic strains of Claviceps purpurea.

A direct relationship between alkaloid synthesis and conidia formation was observed in a series of mutants of the saprophytic fungus Claviceps purpurea 129 which produces high quantities of clavine alkaloids (4500 microgram-ml-1). Sclerotia-like mutants forming mostly arthrospores and only a low number of conidiospores were exceptional in that they were characterized by an inverse relationship between alkaloid synthesis and conidial formation. Conidiospores of the parent strain 129 differed both in their size and ultrastructure. They include oval microconidia (2 X 3.5 micrometer) and prolonged macroconidia (2 X 10.5 micrometer). Both conidial types originated on short lateral sporophores terminated by phialids. Most conidia were characterized by electron-dense cytoplasm with a number of lipidic inclusions; a  minority of conidia contained granular cytoplasm and vacuoles with membrane invaginations. Bicellular conidia were only rarely observed.


Effect of naturally occurring apatites on growth and morphology of algae.

Crystals (30--100 micrometer) of selected naturally occurring apatite (Ca10 (PO4)6(OH, F)2) samples were added to P-free (less than 0.001 microgram/ml total P) Bristol's medium (1-1000 microgram/ml of apatite) as the sole source of ortho-PO43-. The media were inoculated with washed, non-axenic cells of three chlorophycean algal species cultivated under PO43--deficient conditions. Phase-contrast and scanning electron microscopy revealed that at low slurry densities (1-10 microgram/ml of apatite), Ankistrodesmus braunii (ATCC 2744) cells were morphologically distorted. At concentrations of 100 and 1000 microgram/ml of apatite, more than 85% of the cells had undergone autospore formation within 7--10 days of incubation at 20 degrees C. Most autospores formed failed to germinate under high nutrient conditions. Scenedesmus longus (No. 1236) formed colonies when cultivated in Bristol's medium but daughter cells displayed a Chodatella-like unicellular morphology when grown in apatite media. Test algal species (Chlamydomonas dysosmos, S. longus, A. braunii) showed a marked preference for growth on apatite crystals over non-nutritive surfaces. Unialgal and mixed-algal cultures produced an extensive matrix of extracellular fibrous material in response to growth on crystals at concentrations greater than 10 microgram/ml of apatite.


Citric acid cycle enzymes and nitrogenase in nodules of Pisum sativum.

Activity of isocitric dehydrogenase (isocitrate dehydrogenase (NADP+); EC 1.1.1.42) in bacteroids is highest at the time of maximum nitrogen fixation. It is likely that isocitric dehydrogenase is the source of reductant for dinitrogen fixation.


Ultrastructural characterization of goblet-shaped particles from the cell wall of Flexibacter polymorphus.

The ultrastructure of submicroscopic goblet-shaped particles ("goblets') from the cell wall of the marine-gliding microbe Flexibacter polymorphus was investigated. The goblets, which were partially purified by CsCl density-gradient centrifugation, were rich in protein, exhibiting a single absorption maximum in the ultraviolet at about 276 nm; they also contained a small amount of carbohydrate. As determined by electron microscopy, goblets negatively contrasted with ammonium molybdate were about 30 nm in diameter by 36 nm in length. When viewed in profile, each apparently consisted of five morphologically distinct kinds of components: the C-1, C-2, and C-3 subunits which formed the cup-shaped moiety of the goblet; a globular base unit; and a tubular stem-like structure connecting the cup with the base unit. In addition, a long fiber emerged from the interior of some goblets. The fine structural evidence suggested that goblets may be constructed from three stacked subunit rings (each composed of repeating C-1, C-2, or C-3 protomers) arranged concentrically. X-ray images of a clay model closely resembled electron micrographs of negatively stained goblets; thereby lending support to the proposed structure. It is speculated that goblets function in vivo as macromolecular pores through the outer membrane which mediate extrusion of extracellular fibers, possibly of importance in gliding motility or in attachment of cells to solid surfaces.


ICMSF methods studies. IX. The influence of selective enrichment broths, differential planting media, and incubation temperatues on the detection of Salmonella in dried foods and feed ingredients.

Ninety-eight dried foods and feed ingredients were analyzed for Salmonella using tetrathionate brilliant green (T) and selenite cystine (S) broths incubated at 35 and 43 degrees C. The four enrichment cultures for each sample were subcultured in duplicate onto brilliant green (BG) , Salmonella--Shigella (SS), and bismuth sulfite (BS) agars, one plate of each being incubated at 35 degrees C, the other at 43 degrees C. Salmonellae were isolated from 44 of the 98 samples. Differences in the Salmonella recovery rates from the four selective enrichment conditions were not significant. However, there was a trend toward a higher proportion of Salmonella colonies on the selective media when the enrichment broths were incubated at 43 degrees C, although the differences were significantly only with BG and SS subcultured from T. While the four enrichment systems were not significantly different, the trend toward a higher proportion of Salmonella colonies on the differential media subcultured from 43 degrees C enrichment broths indicates an advantage to incubation at the elevated temperature. Incubation of selective agars at 35 degrees C was best because at 43 degrees C Salmonella recovery was significantly reduced. Detection of salmonellae on BS was significantly better than on BG or SS.


A procaryotic intracellular symbiont of the Great Salt Lake brine shrimp Artemia salina (L.).

Individuals of Artemia salina, the brine shrimp, were captured from the Great Salt Lake, a highly saline (330--340 g (see formula: solids content) terminal lake in Utah. Electron microscopy revealed the presence of intracellular procaryotic symbionts in the epithelial lining of the midgut. Fine structure and possible role of the symbiont are discussed.


Polarity in the exponential-phase Rhizobium japonicum cell.

Highly distinctive aspects of the exponentail-phase Rhizobium japonicum cell were disclosed by means of thin sections, freeze etching, fluorescent antibodies, and ruthenium red staining. Polarity was expressed in the form of reserve polymer distribution near one end of the cell and as cytoplasmic localization near the opposite end. In addition, exocellular polysaccharide (EPS) accumulated preferentially around the cytoplasmic end, and the feature described previously as an "immunofluorescent polar tip" was seen clearly as an extracellular polar body (EPB) on the tip of the cell at the reserve polymer end. Compartmentalization of cytoplasm and reserves were consistent features of nearly all exponential cells of the two strains studied; strain 31, however, formed little EPS and had a high incidence of a large, tightly bound EPB, while strain 138 formed EPS extensively and had a low incidence of EPB. Extracellular polysaccharides of strain 138 reacted with soybean lectin in gel diffusion tests, so that the EPS seen in electron micrographs is tentatively considered to include the lectin-binding material. Extracellular polar bodies were accumulations of granular and fibrillar material with properties consistent with the presence of polysaccharide and lipopolysaccharide. The role of EPB in cell to cell attachment was confirmed by electron microscopy.


The formation of macroconidia in dermatophytes following UV irradiation and temperature treatment.

The ability of sterile hyphae of Epidermophyton and Microsporum to produce macroconidia was restored by exposing hyphae to ultra violet irradiation followed by prolonged incubation at 35 degrees C. The four species of Trichophyton used in the present study did not produce macroconidia after such treatments.


Carbon source dependent differences in the composition of the cell walls of the basidiomycete Picnoporus cinnabarinus.

A wild-type monokaryotic strain of Picnoporus cinnabarinus grown on glucose produced shorter and thicker hyphae than cultures grown on acetate. Colonies from glucose media were smaller and more compact than acetate-grown colonies. Chemical and enzymatic analysis of the isolated cell wall of both morphological types showed that the amount of amino sugars and the ratio glucosamine:galactosamine were higher in the acetate-grown cells. This may be the cause of morphological differences observed.


Prevalence of gallstones and gallbladder disease in Canadian Micmac Indian women.

The prevalence of gallstones and gallbladder disease was studied between October 1973 and June 1976 in Canadian Micmac Indian women aged 15 to 50 years in an inland rural community near Shubenacadie, NS. Of 132 women at risk 98 underwent cholecystography, 6 had a history of cholecystectomy (verified from hospital records) and 3 had cholecystectomy because of cholecystitis during the 3 years of the study. Of the 17 abnormal cholecystograms 10 showed radiolucent gallstones, and repeated studies documented gallstones in 6 of the 7 radiographs on which the gallbladder was not visualized. The prevalence of gallstones was found to be 211/1000, and that of gallbladder disease, 240/1000. The peak prevalence was at 30 to 39 years of age. The women with gallbladder disease were significantly more obese and of greater parity than those without gallbladder disease even when age was controlled. The Micmac Indian women of Nova Scotia appear to be at a much higher risk for the development of cholesterol gallstones and gallbladder disease than Caucasian women in Framingham, Massachusetts.


Classification of degenerative arthritis.

It is suggested that the former division of degenerative arthritis into idiopathic types and those secondary to some disease process is no longer valid. Recent studies have indicated that abnormal concentrations of force on cartilage lead to the development of this disease. A classification is presented that is based on the assumption that the process is initiated by abnormal concentrations of force on normal cartilage matrix, normal concentrations of force on abnormal cartilage matrix or normal concentrations of force on normal cartilage matrix that is supported by bone of abnormal consistency.


Treatment of bone disease with dihydrotachysterol in patients undergoing long-term hemodialysis.

Nine of 24 patients undergoing long-term hemodialysis were found to have evidence of moderate to severe bone disease. Two had bone pain and muscle weakness and two had pseudofractures. Eight of the nine were treated with dihydrotachysterol (DHT), 0.25 to 0.375 mg/d initially, but four required doses between 0.5 and 1.0 mg/d. Ther serum alkaline phosphatase value decreased in all patients and returned to normal in six. The bone pain and muscle weakness resolved and the pseudofractures healed. Bone biopsies in six patients before and after initiation of treatment with DHT showed that the osteoid area decreased significantly from 29.6 +/- 22.8% (mean +/- standard deviation) to 11.5 +/- 7.5% (P less than 0.025) and the resorptive surface decreased in all patients. DHT, in doses of up to 1.0 mg/d, is effective in treating both the osteitis fibrosa and the osteomalacic components of bone disease in patients undergoing hemodialysis.


Portal hypertension complicating myelofibrosis: reversal following splenectomy.

Portal hypertension occurs in approximately 10% of patients with myelofibrosis. Increased portal blood flow secondary to splenomegaly has been proposed to explain its development. In a 60-year-old woman with proven myelofibrosis of 10 years' duration and gross splenomegaly, portal hypertension developed with esophageal varices and ascites. There was no demonstrable obstruction to portal blood flow. Following splenectomy the ascites and esophageal varices disappeared. Despite the presence of splenic myeloid metaplasia, splenectomy did not impair the patient's hematologic status. Portal hypertension complicating myelofibrosis has a poor prognosis, so careful attention should be given to its detection. Splenectomy may be preferable to portal-systemic shunting in the management of this complication.


Treatment of obesity by exercise in the cold.

Six obese men aged 25 to 46 years exercised vigorously for 3 1/2 hours in a cold chamber (-34 degrees C) on 10 successive days. There was an early water loss of about 1 kg, probably due to mobilization of glycogen stores, and a subsequent fat loss of about 4 kg (as estimated from readings of skinfold thickness and confirmed by underwater weighing). The total fat loss was much greater than the calculated external energy deficit (as estimated from dietary records, an activity diary and use of a Kofranyi-Michaelis respirometer). Although some energy was "wasted" through ketosis, much of the additional energy was apparently used for synthesis of additional muscle protein. Both readings of skinfold thickness and underwater weighing indicated that the loss of adipose tissue was well sustained in the first 2 months after the exercise program. Further experiments are recommended to determine whether cold exposure makes a specific contribution to the observed weight loss, and whether this approach would be equally effective in a larger and less selected sample of obese patients.


[Student enrollment in Canadian medical schools, 1976-77].

The 1976-77 statistical study of medical school enrollment by the Association of Canadian Medical Colleges shows that total enrollment in Canadian medical schools had increased 103.8% since 1960-61, although the rate of increase had decreased to almost zero by 1976-77. Women accounted for 30.3% of the total enrollment in 1976-77 (for all years of the course), which represents an increase of more than 550% in the 17-year period; for the 16 schools the proportion ranged between 23.9% and 43.8%. Enrollment of foreign students had decreased from 340 in 1966-67 to 90 (1.2%) in 1976-77; 71 of the 90 students were American. For the entire nation the mean number of medical students per 10 000 population was 3.1, but in British Columbia the figure was only 1.5. Of the Canadian and landed immigrant students 94.5% were attending medical school in their home province.


Severe myelosuppression from piperazinedione, (NSC No. 135758), cyclophosphamide plus dimethyl-triazeno-imidazole carboxamide (DTIC).

In order to determine whether piperazinedione used in low doses in combination with cyclophosphamide plus dimethyl-triazeno-imidazole carboxamide (DTIC) produced variable or severe myelosuppression, a Phase I Study was performed in 10 patients who received 16 courses of the three-drug combination. Although mild myelosuppression was consistently observed at doses of 4 mg piperazinedione, 400 mg cyclophosphamide, plus 400 mg DTIC, variable, severe, and prolonged myelosuppression was seen in three of six patients who received a dose of each of the drugs only 25% higher. The only other abnormality observed was nausea and vomiting. This study indicates that low doses of piperazinedione can produce variable and severe myelosuppression when used in combination with other myelosuppressive agents, and that only small increments in dosage may produce marked increases in the degree of myelosuppression. Future combination chemotherapy regimens employing piperazinedione should undergo cautious Phase I toxicity testing to avoid severe depression of blood counts.


Combination chemotherapy in abdominal Burkitt's lymphoma.

In a clinical trial, 42 patients with abdominal Burkitt's lymphoma (BL) were treated with a combination regimen, code-named CVA, consisting of cyclophosphamide (CTX), vincristine, and cystosine arabinoside. In addition, intrathecal methotrexate (i.t. MTX) was administered as prophylaxis against subsequent central nervous system (CNS) involvement. Induced remissions, relapse, and survival were compared with those in a preceding group of 44 patients with abdominal BL treated with CTX along. Remission rate did not differ significantly in the two treatment groups, although induced remissions were higher in the CVA plus i.t. MTX-treated group (94% vs. 83%). Remission duration was significantly increases (p less than .05) and CNS relapse significantly reduced (p less than .05) in the group treated with CVA and i.t. MTX. The combination therapy was associated with higher early deaths during treatment, which adversely affected the overally survival. It is suggested that a reduction of the initial chemotherapeutic doses, particularly for patients with extensive tumor load, could further improve on the results of this trial.


Treatment of acute nonlymphoblastic leukemia in children with a multiple-drug protocol.

Twenty-one children with acute nonlymphoblastic leukemia (ANLL) were treated with a combination regimen consisting of arabinosyl cytosine (Ara-C), 6-thioguanine (TG), and Adriamycin, The incidence of complete remission was 74%. For consolidation, addition courses of Ara-C and TG were given, followed by L-asparaginase. The maintenance program was the same as that for the lymphoblastic type (L-2) including intrathecal methotrexate for prophylaxis of meningeal leukemia. Of the 16 who were evaluable for the duration of complete remission, six developed bone marrow relapse, one meningeal leukemia within 3-14 months after entering complete remission and one was lost to follow-up. Eight remain in complete remission for 9-72 months. In five of eight, chemotherapy has been terminated after 3 years, and all continue in remission for 11-32 months post-treatment. Although the results do not compare well to those of the lymphoblastic morphology, long-term disease-free survival can be achieved with multiple-drug intensive treatment in childhood ANLL.


The relative roles of gallium-67-citrate scanning and lymphangiography in the current management of malignant lymphoma.

The usefulness of gallium-67-citrate scanning and lymphangiography in the detection of iliac and paraaortic lymph node involvement was evaluated in 53 patients with Hodgkin's disease and non-Hodgkin's lymphomas who subsequently underwent laparotomy. Our data suggest that the overall accuracies of the two procedures in this regard are comparable. Although in this anatomic area the gallium scan tends to underestimate the presence of disease (higher false-negative rate), the false-negative rate is quite low. The false-negative rate with lymphangiography is lower than with scanning but it tends to overestimate the presence of disease (higher false-positive rate). It was concluded that gallium scanning should be an integral part of the staging of lymphomas and a schema for their clinical staging based on the use of gallium scanning early in the diagnostic sequence is proposed.


Analysis of the cycling and noncycling cell population of human solid tumors.

The size and kinetics of the cell population of six advanced human solid tumors were analyzed following the continuous infusion of H3-TDR for a period of 6 to 21 days. By using the labelling indices of the cells in interphase and mitosis, and the rate of label incorporation, it was found the only 10 to 40% of the tumor cell population was replicating at any given time. Fifty-five percent to 85% of the remaining cell mass eventually entered into cycle at least once. Anywhere from 5% to 40% of the cell population remained arrested in G2 or G0 in individual cases during the period of observation. The significant size of the "resting" cell compartment is undoubtedly one explanation for the relative insensitivity of advanced adult solid tumors to current cell cycle-oriented therapeutic regimens.


Atypical fibroxanthoma of the skin: an ultrastructural study of two cases.

The ultrastructure of two atypical" fibroxanthomas of the skin was studied. The first lesion was a spindle cell tumor on light microscopy, which electron microscopy revealed was composed of undifferentiated mesenchymal cells. The second lesion had a highly pheomorphic appearance on both light and electron microscopy. It was formed by atypical histiocytic cells and abundant "typical" Langerhans cells. The second lesion was considered to be a proliferation either of atypical Langerhans cells or of histiocytes related to Langerhans cells. Thus, atypical fibroxanthoma of skin may not be a homogeneous entity but could be a group of mesenchymal proliferative lesion in a similar clinical setting.


The effect of surgical resection of experimental "primary" adenocarcinoma of the colon of survival and incidence of metastases.

The effect of surgical resection of "primary" tumors classified by size at the time of resection has been studied in two tumor cell lines derived from dimethylhydrazine-induced colonic neoplasms in the Buffalo strain rat. Surgical treatment of colon cancer in the rat yields results similar to those for human carcinoma. Some of the smallest tumors resected were associated with metastases and this finding suggests a need for effective postoperative adjuvant therapy. The incidence of metastases and the size of the tumor were inveresely related to survival, e.g., the smaller the tumor or the sooner the excision, the greater the survival of the animal. The operated animal model studied here could prove to be very useful for evaluating various forms of systemic therapy for the control of micrometastases associated with colonic neoplasms.


Naked megakaryocyte nuclei: a clue to malignancy.

Bone marrow smears from 63 patients with various malignancies and a series of 51 controls were examined for the presence and percentage of naked megakaryocyte nuclei (NMN). Patients with malignancy had more than 15% NMN, which, when compared with the incidence in controls, was statistically significant. The etiology of this artifact is unknown. It is a clue to the presence of malignancy, and might be useful in following treated cases of malignancy for evidence of relapse. NMN should not be confused with metastatic malignant cells.


Primary malignant tumors of the thyroid gland: a clinicopathologic study of 254 cases.

Of 254 primary malignant tumors of the thyroid gland diagnosed in the pathology department of the University of Cape Town, 212 (83.5%) were differentiated carcinomas. In this differentiated group, tumors composed exclusively of papillary structures exhibited the most favorable prognosis; local recurrences and/or spread were noted in tumors with a mixed papillary and follicular pattern and, more commonly association with 21 tumors (8.3%) but an associated multinodular goitre was found in only nine patients (3.5%). In addition to the well-known preponderance of thyroid carcinoma in women, a majority of lesions occurred in white patients in this series despite a higher hospital admission rate for coloreds (mulattos).


Watery diarrhea syndrome in an adult with ganglioneuroma-pheochromocytoma: identification of vasoactive intestinal peptide, calcitonin, and catecholamines and assessment of their biologic activity.

A case of adult ganglioneuroma-pheochromocytoma with an associated watery diarrhea syndrome is reported. High levels of vasoactive intestinal peptide (VIP) were found in preoperative serum and in tumor tissue. The serum VIP levels fell to normal, and the watery diarrhae syndrome completely ceased following removal of the tumor. In addition to containing VIP, the tumor was rich in catecholamines, and calcitonin. Peptide hormone-containing extracts and catecholamine extracts from the tumor both activated the adenyl cyclase system and increased lipolytic activity in a preparation of isolated rat fat cells. The findings in this patient further link VIP with neural crest tissues, and suggest the importance of determining catecholamine levels in patients with the watery diarrhea syndrome.


A clinical and pathological staging system for soft tissue sarcomas.

A system for staging the clinical status of patients with soft tissue sarcomas is presented, based on the clinical characteristics of the primary tumor (size, extension), the involvement of lymph nodes, the presence of metastases, and the grade of the tumor. This represents the TNM system with grade of tumor (G) added. The system evolved was based on examination of 1215 cases of 13 types of soft tissues sarcomas, primarily in the extremities (fibrosarcoma, liposarcoma, etc.). Nine stages are described, and they are correlated with survival in the cases reviewed. The staging system now can be used for case evaluation for therapy determination and for intercomparison of series of patients as to incidence of different kinds of tumors, effects of treatment, and survival.


Factors affecting estrogen receptors in breast cancer.

Estrogen receptor contents (ER), determined by a sucrose gradient method in 250 primary or metastatic breast cancers, were analyzed with respect to the influence of the patient's menopausal status, chemotherapy, and tissue sampling. The incidence of the presence of estrogen receptors (ER+) increased in the order of para-, pre- and postmenopausal status of the patient, suggesting that a tumor occurring at the paramenopausal phase tends to be a hormone-independent type. Chemotherapy did not alter the incidence of ER(+), nor the quantity of ER in metastatic lesions. Multiple biopsies done simultaneously or sequentially in the same patient are consistent in their qualities and quantities of ER, provided histological confirmation and examination of the amount of cellularity are included in the process of interpretation.


Sarcomas of the breast: a clinicopathologic analysis of ten cases.

The clinical and pathologic features of ten mammary sarcomas are discussed. Tumor size, contour, degree of cellular atypia, and mitotic activity were specifically evaluated to determine if they are important indiced of clinical behavior. Results indicate that infiltrating margins, 2-3+ stromal atypia, and eight or more mitoses per 10 HPF are characteristics of neoplasms associated with a poor prognosis. Tumor size was an unreliable criterion. A classification of breast sarcomas is presented with an appeal to avoid use of the term "stromal sarcoma" as a specific pathologic diagnosis. Since a diagnosis based upon cell of origin and correlated with the above morphologic features is fundamental to an intelligent therapeutic approach to this rare group of neoplasms, future reports dealing with this subject should include these details.


Parachordoma: a new clinicopathologic entity.

Parachordoma is a tumor that was established and described by Laskowski in 1951. It is a rare tumor, which appears adjacent to tendons, synovium, and even osseous structures. It is lobular and pseudoencapsulated. Histologically, in some ways, it is compatible with the chordomas of bone with a constant fibrous tissue component. It grows slowly and is only locally invasive. If not adequately excised, it is prone to recur, but complete surgical removal is usually possible. Its exact histogenesis remains obscure. This tumor may have some relationship to the great vesicular cells of chordoid tissue described by Schaffer as "blasige Zellen von chordoiden Gewebe" developing from special synovial cells. Ten cases collected over a period of 26 years at the Institute of Oncology in Warsaw are presented.


Transfer of tumor-specific immunity with syngeneic spleen cells and serum from mice that have large tumors and metastases.

Experiments were designed to assess 1) relative immunity after adoptive transfer of spleen cells or serum from tumor-bearing mice to untreated syngeneic mice, and 2) the degree of tumor-specific transplantation immunity imparted by cells or serum relative to tumor size  and the presence of metastases in the donor at the time of spleen cell or serum transfer or after in situ necrosis of the primary tumor by cryosurgery in a CDF1-sarcoma system. Viable lymphoid spleen cells or serum from normal mice had no effect on tumor growth. Serum from mice that had large tumors and gross metastases induced a protective effect similar to that found after cryosurgery of the primary tumor. Serum from mice with small tumors and spleen cells from animals bearing either small or large tumors failed to induce immunity consistently. In no instance did serum from tumor-bearing mice induce enhancement of tumor growth.


Skin tests with soluble melanoma antigens in patients with choroidal tumors.

The cutaneous delayed hypersensitivity reactions with a soluble melanoma antigen in patients with choroidal mass lesions were studied. Ninety percent of patients with pathologically documented choroidal melanomas had positive melanoma antigen skin test responses. There did not appear to be any difference in the histologic appearance of the tumor nor in the disease status of those patients with positive versus those patients with negative skin test reactions. A 21% instance of false-positive responses with this partially purified soluble melanoma antigen in patients with simulating lesions was observed. The cause for this reactivity is unclear; however, from previous work tissue-associated antigens or fetal antigens are the most probable etiologies for the false-positive melanoma antigen skin tests observed. Further purification of the melanoma-associated antigen preparation may increase the specificity. The results of this study would mitigate against the use of this soluble melanoma antigen skin test in the primary evaluation of patients with pigmented choroidal mass lesions. Currently, the assay is being tested to ascertain its correlation with prognosis and as a means of monitoring immunotherapy.


The pathology of breast cancer detected by mass population screening.

Breast cancer was detected in 156 of 17,526 asymptomatic women, (8.9/1000), aged 45-64 years, screened by mammography, thermography, and physical examination, Twenty-six percent of 149 pathologically reviewed cases metastasized to axillary nodes. Thirty-six percent of tumors were in situ, minimally invasive, or low grade tubular carcinomas, none of which metastasized. Increased rates of detection were shown for intraductal and tubular types. Frankly invasive ductal and lobular carcinomas had a mean diameter of 2.3 cm., 46% of which had axillary lymph node metastases. Seventy-percent of these were to only one to three nodes, however. Multicentricity with intraductal and lobular carcinoma in situ was frequently observed. Metastatic potential was related to tumor size, degree of stromal invasion, lymphatic permeation, and histologic grade. Few histological parameters other than size could be considered favorable. Forty-two percent of tumors were not palpable, the majority being in situ, minimally invasive, and tubular types. Only five nonpalpable invasive carcinomas metastasized. While the initial results of mass screening appear favorable, prolonged follow-up is needed to determine its impact on the population at risk.


Familial cancer in the general population.

In the course of collecting samples of human milk for the National Cancer Institute, family histories have been assembled since 1971. Ages, causes of death, reproductive histories, and the history and age of occurrence of cancer were obtained for all first degree relatives of the proband's parents. Two thousand and ninety cancers were identified in 31,945 persons. Cancers were confirmed by pathology reports, hospitals' and doctors' records, or death certificates. Of the family lineages, 65.9% had no cancers and 8.0% had two or more. For all cancers taken together, clustering was not significant but there was significantly more observed than expected cancers in lineages with cancer of breast, ovary, skin, corpus uteri, stomach, rectum, lung and bronchus, or colon. Little or no excess was observed in lineages with leukemia, lymphoma, and cancer of the cervix or prostate. The relative risk of breast cancer was increased 1.5 times for daughters and 3.8 times for sisters of women with the disease.


Variation in the appearance of giant condyloma in an Ungandan series of cases of carcinoma of the penis.

Whole mount sections were made from all amputation specimen of patients treated for carcinoma of the penis in Mulago Hospital, Kampala, Uganda, during a 21-month period in 1968-1970. Among a total of 55 cases four tumors were found which were large, but histologically showed low invasiveness suggestive of absence of metastatic spread. There were two giant condylomas, and two giant condylomas showing possible microinvasion. Two further cases showed a small squamous cell carcinoma together with a giant condyloma in the remainder of tumor. The most chracteristic feature was an orderly, well-circumscribed, expansive downgrowth, leaving little stroma to be seen between the epithelial masses to tumor. Within these limits, however, the spectrum of growth pattern, differentiation, and malignant change was very wide and much more varied than in tumors recorded form Western countries. This should be remembered when a presumptive diagnosis of the condition is to be made on small routine biopsies. Additional changes showing marked similarities to condylomata acuminata were often seen in superficial portions of tumor. This transition in histological picture within one tumor favors the view that giant condyloma is an intermediate lesion in the development of cancer in condylomata acuminata.


Surgical treatment of penile cancer: a follow-up report.

One hundred and fifteen patients with penile cancer were treated at Roswell Park Memorial Institute from 1952 to 1975. A full follow-up is reported and factors involving the prognosis are analyzed. Although the clinical error of staging was near 30%, the lymphography results suggest that this study may result in added improvement in preoperative staging. Early diagnosis, adequate surgical resection, and lymph node dissection will improve the survival significantly. When dealing with an individual patient the prognosis is poor when any one or more of the follow factors are present: the lesion involves the shaft; there is a positive margin at the surgical resection; total penectomy is necessary to obtain tumor-free margin; lymphography is positive for tumor involvement of lymph nodes; lymph node dissection has not been performed; positive  lymph nodes are found on surgical exploration. The good prognostic factors include: a lesion confined to the glans and partial penectomy is sufficient to obtain a tumor-free margin of resection; no clinical evidence (including lymphography) of lymph node invovlement; performance of lymph node dissection. The histological grading of the tumor should not influence the clinical decision for treatment in our opinion at this time, based on our current results. Further prospective studies of different factors involved in etiology, diagnosis, and treatment of penile cancer are suggested.


Observations on growth rate of breast carcinomas and its possible implications for lead time.

Doubling times were estimated for 15 breast carcinomas in 13 patients, and were found to be between 42 and 397 days with the average at 211 days. The mean lead time at mean growth rate from the average size of 44 preclinical to the average size of 118 clinical tumors was estimated to be 3 years. This period may be considered the probable time gained through screening for mammary carcinomas by the methods used in our studies, particularly single-view mammography. However, the wide range of observed growth rates and tumor sizes and probably measurement errors decreases the validity of this study.


Bone marrow involvement in Burkitt's lymphoma.

Thirteen patients with a malignant lymphoma exhibiting the cytologic characteristics of Burkitt's lymphoma manifested marrow involvement at the time of initial diagnosis (11 patients) or later in the course of the disease (two patients). Eleven patients were 16 years of age or younger. Eight had evidence of abdominal disease, five in the ileocecal area. Despite extensive marrow involvement in most of these patients, frankly leukemic blood pictures were uncommon. Platelet counts and absolute neutrophil counts were frequently normal. Membrane surface markers were studied in four patients. The malignant cells from three exhibited mulambda surface immunoglobulin; the cells from the other manifested muk surface immunoglobulin. All of the patients had a rapid clinical course in spite of intensive chemotherapy. The median survival from detection of marrow involvement was 2.5 months.


Multiple primary cancers: relative risk in New Mexico's triethnic population.

A review of the population-based New Mexico Tumor Registry data identified 446 patients with nonsimultaneous multiple primary cancers, excluding non-melanoma skin cancers and carcinomas in situ of the uterine cervix. Expected numbers of cases were established by observing the person-years of exposure to the risk of developing a second or subsequent primary cancer and then applying the appropriate locally determined age-, sex-, ethnic-, and site-specific cancer incidence rates. The relative risk (observed/expected) of developing a second primary cancer was elevated for "Anglo" and Spanish American cancer patients in comparison with the risk of developing a first primary cancer in persons who have never had one. Only six cases of nonsimultaneous multiple primary cancer were observed (6.39 expected) in the region's American Indian population. There were differences in site-site associations among the three ethnic groups, but in many categories there were too few cases for analysis.


Multiple primary cancers at Memorial Hospital 1949-1962.

The Memorial Hospital, New York, surveys of multiple primary cancer risks undertaken during 1965-1971 are summarized. After re-examination the methodological problems noted were: 1) that prospective studies tell us more than prevalence or retrospective studies; 2) that risks must be related to the observation period, patient's ages, etc.; 3) that hospital series probably are selected but that this may be overcome by internal comparisons; 4) that the search for explanatory variables is difficult, to the extent data on these variables were not explicitly collected; and 5) that computing multiple risk ratios for each of many cancer types guarantees a number of accidentally statistically significant results. It was also concluded that most cancer patients have excess risk for specific later cancers, depending on their original cancer type and that knowledge of these risks is of true clinical importance.


Multiple primary cancers: review of clinical studies from two Missouri hospitals.

A composite review of a series of hospital-based, clinical studies on the prevalence of simultaneous and nonsimultaneous multiple primary cancers, including those in which data were recorded by the life table method for six different series of cancer patients and one "control" series of patients who did not have cancer at first contact is provided. The studies came from Barnes Hospital and the Ellis Fischel State Cancer Hospital (EFSCH) and span the period from 1914 through 1964. The conclusions of the studies support the concept that the presence of one primary cancer neither increases nor decreases the chances for developing additional cancers with the possible exception of a few "target organ" areas. One study of this period showed a nonrandom distribution of patients with multiple primary cancers referred to EFSCH and this observation merits further epidemiologic research.


Role of heredity in multiple primary cancer.

The occurrence of multiple primary malignant neoplasms characterizes virtually all varieties of hereditary cancer. This report focuses on this phenomenon in 11 families with the Cancer Family Syndrome (heritable adenocarcinomas of the colon and endometrium) and a single extended kindred with site-specific colon cancer. Of the 316 relatives with cancer in the 12 families, 68 (21.5%) had two or more primary malignancies and 59 (86.8%) of these multiple primaries involved the colon and/or endometrium. A pooled analysis of this resource revealed a consistent 3% risk for a second primary cancer in each year of survival following first onset. If a second primary occurs, the risk for a third is extremely high (6.9% per year), but shows a nonlinear trend with increasing survival following second onset. The high risk for development of extraprimary malignancies in patients from these kindreds indicates that careful consideration should be given to total removal of their principal target organs following the initial manifestation of cancer.


Breast cancer in families.

An analysis of 489 breast cancer pedigrees was conducted to determine the age at diagnosis and bilaterality rate in 887 patients with different familial patterns of the disease compared with 5,100 unselected patients, and to estimate the lifetime probabilities of breast cancer development in 983 daughters of familial patients. The familial patients had higher rates of bilaterality and were younger at diagnosis than patients in an unselected series. Bilaterality rates were highest in young patients. Familial bilateral patients developed their first primaries about 5 years earlier than unilateral patients. Daughters of patients with any type of family history of breast cancer exhibited a 23% lifetime probability for the disease. The highest probability (27%) pertained to daughters of patients whose mothers were also affected, and it was concluded that this group referred to a hereditary type of breast cancer distinct from types involving associated neoplasms. The occurrence of multiple neoplasms characterizes the hereditary types of breast cancer.


Discussion: genetics of multiple primary tumors: a clinical etiologic approach illustrated by three patients.

Clinicians can shed new light on the genetic and environmental origins of cancer, particularly multiple primary malignancies, by asking additional questions at the bedside. Areas to explore include occupational history, personal habits, residence, and medical and family histories with emphasis on subtle clues of disorders predisposing to cancer, such as birth defects and benign neoplasms. When this bedside approach to cancer etiology was applied to three patients with a total of 19 primary malignancies, the most striking finding was a variety of benign neoplasms in the patients and a similar array of benign and malignant tumors among first-degree relatives, some of whom also had multiple primary tumors. A single gene trait, Cowden (multiple hamartoma) disease, was recognized in one patient. It is suggested that, in future studies of multiple tumors, epidemiologists consider not just malignancies, but all forms of neoplasia, both in the patient and in the family.


Statistical methods for studying multiple primary malignant neoplasms.

Case reports and case series dealing with multiple primary malignant neoplasms provided useful criteria for defining and documenting this phenomenon. The formation of tumor registries greatly aided in identifying a sufficient number of multiple primary cancer patients and facilitated case-control comparisons. Reports of two or more neoplasms occurring together in the same individual do not constitute proof of a significant association; the tumors must be shown to occur together more frequently than expected by chance. The person-years approach applied to data derived from a well-defined population makes it possible to compare the observed and expected number of subsequent primary cancers. The results of the most sophisticated procedures are no better than the quality of the data, however, and one must critically examine possible sources of bias before accepting statistical significance as representing biologic significance.


Second malignant tumors after cancer in childhood.

Studies were made of the development of second malignant tumors in children treated at the Sidney Farber Cancer Institute. In 1973 a retrospective analysis identified second cancers in 15 of 410 patients who survived a childhood cancer. During the period 5-24 years after diagnosis of the first cancer, the cumulative probability of developing a new cancer was 12%. This frequency was approximately 20-fold higher than the expected rate for the general population. Prospective study of the series since 1973 has identified a second primary cancer in five additional patients. The majority of second cancers were in the field of prior radiotherapy, and were attributable to the oncogenic effect of radiation. Genetic susceptibility factors were identified in individual patients.


Multiple primary cancer risk after therapy for Hodgkin's disease.

Forty-four antecedent, synchronous, and metachronous multiple primary cancers were identified among 41 patients who constituted 4.0% of 1028 patients initially treated for Hodgkin's disease during the years 1950-1954, 1960-1964, and 1968-1972. At 5 years post-therapy the cumulative probabilities of developing a multiple primary cancer for patients treated in 1950-1954, 1960-1964, and 1968-1972, were 1.14%, 1.48%, and 4.43%, respectively. At 10 years the cumulative probability of a multiple primary cancer was 2.54% for the 1950-1954 treatment group and 6.52% for the 1960-1964 treatment group. Among those patients 16-39 years of age, initially treated during the period 1960-1964, who had survived 6-10 years after receiving radiation plus single agent chemotherapy, we observed a significant 18-fold increase in the number of multiple primary cancers. A significant occurrence of two multiple primary cancers in a relatively small group of patients treated with chemotherapy only during the period 1968-1972 was also noted. Continued surveillance of patients extensively treated with combination chemotherapy and radiotherapy will enable assessment of the oncogenic potential of these modern therapeutic approaches to the management of Hodgkin's disease.


Bioassay program for carcinogenic hazards of cancer chemotherapeutic agents.

Various compounds and combinations thereof, of promise in the treatment of neoplastic diseases, were tested for possible carcinogenicity in Swiss mice and Sprague-Dawley rats. Some of the compounds were fairly active carcinogens, while others showed little or no evidence of carcinogenicity. The carcinogenicity of the drug combinations was generally less than that of the individual components.


A death certificate analysis of nasal cancer among furniture workers in North Carolina.

A case-control study of nasal cancer, based on death certificate statements on occupation in North Carolina counties with furniture-manufacturing industries, revealed a 4-fold excess risk linked to this occupation. Although woodworking exposures have been associated with nasal adenocarcinomas in several areas of the world, this is the first report of such a relationship in the United States.


Metabolism of  three cyclic nitrosamines in Sprague-Dawley rats.

The metabolism of three cyclic nitrosamines has been studied in Sprague-Dawley rats. The compounds were nitrosopyrrolidine, nitrosohexamethyleneimine, and nitrosohepatamethyleneimine and were labeled at the alpha carbon with 14C. At low doses (2 to 4 mg/animal) the compounds were metabolized to 14CO2 to the extent of 77, 43, and 27%, respectively, after 24 hr. At doses closer to the 50% lethal dose of the compounds (70 to 160 mg/animal) the metabolism values were only 14, 4, and 8%, respectively, after 24 hr. The significance of these results is discussed.


Effect of high-risk diets for colon carcinogenesis on intestinal mucosal and bacterial beta-glucuronidase activity in F344 rats.

The effect of high-protein (beef or soybean protein) and high-fat (beef fat, corn oil, or lard) diets on large intestinal bacterial and intestinal mucosal beta-glucuronidase was studied in female F344 rats maintained on these diets for two generations. Animals fed a 20% corn oil or 20% lard and 20% casein diet had a higher beta-glucuronidase activity in the contents of cecum and colon than did rats fed a 5% corn oil or lard and 20% casein diet. The cecal bacterial beta-glucuronidase activity was higher in animals fed diets with high levels of beef protein (40%) and beef fat (23%) or with high levels of soybean protein (39%) and corn oil (24%) than it was in rats fed diets containing 18.5% beef protein and 6.5% beef fat or 19% soybean protein and 5.4% corn oil. Animals fed diets containing high levels of beef protein and fat or high levels of soybean protein and corn oil had a higher small intestinal mucosal beta-glucuronidase activity than did the other groups. No significant difference was observed in the colonic mucosal beta-glucuronidase activity among the animals fed beef and soybean diets. It is concluded that diets high in fat and high or normal in protein are associated with elevated levels of bacterial beta-glucuronidase activity in the large intestine of rats.


Factor XIII deficiency in BALB/c mice with plasmacytoma.

These studies examined the fate of Factor XIII (fibrin-stabilizing factor) in mice with plasmacytoma (MOPC-300, MOPC-384, MOPC-467, and J-558). Plasma Factor XIII levels in these mice decreased progressively with tumor expansion. No plasma inhibitors of Factor XIII activity could be detected. Factor XIII was found on plasmacytoma cell membranes and in the cytoplasm of the malignant cells by immunofluorescence. The inverse relationship between tumor load and plasma Factor XIII levels suggested that the fibrin-stabilizing factor was absorbed by the malignant cells.


Serum therapy for radiation-induced impairment of immune resistance to metastasis.

The use of serum transfusion to remedy radiation-induced damage to established antitumor resistance was investigated in female C3H mice. The mice, which had been actively immunized against a syngeneic mammary carcinoma, were injected i.v. and s.c. with suspensions of cells from the same tumor and were then given 300 R extensive-field irradiation to the abdomen two times. Tumor cells implanted outside the irradiated area grew better in irradiated mice than in unirradiated controls. Under these experimental conditions, protection could be transferred to radiation-impaired hosts with several injections of cell-free immune serum. Transfers of normal serum provided a detectable but low degree of protection. The corrective effect of serum transfers to radiation-impaired hosts was clearly expressed against pulmonary tumor growth (i.v. challenge), provided the transfusions were started no later than the first day after the injection of the tumor cells. Serum transfusions were ineffective against the growth of tumors implanted s.c. Transfers of serum from hosts carrying large (15 mm) s.c. tumor implants had a negative effect on the resistance of irradiated recipients. The results indicate that humoral resistance factors, both normal and immune, may act against metastatic spread of solid tumors.


Screening for deficits in DNA repair by the response of irradiated human lymphocytes to phytohemagglutinin.

An assay has been developed to measure the ability of human lymphocytes to repair damage to DNA. In this assay, purified human lymphocytes are exposed to graded doses of radiation and then stimulated with phytohemagglutinin to undergo DNA replication. The rate of incorporation of thymidine in irradiated lymphocytes during the second and subsequent rounds of DNA replication is taken to be indicative of the ability of the cells to repair damage to DNA. In lymphocytes from normal individuals, X-irradiation with doses of 100 to 800 rads was found to inhibit phytohemagglutinin-stimulated thymidine incorporation proportionally to the dose of radiation without curtailing the induction of DNA polymerase. The response to phytohemagglutinin of lymphocytes from a patient with xeroderma pigmentosum after exposure to graded doses of X-irradiation was found to be similar to that of the normal controls, whereas the response after ultraviolet irradiation was markedly impaired. In contrast, lymphocytes from patients with ataxia telangiectasia were hypersensitive to X-irradiation. The data on these clinical syndromes support the idea that this assay measures DNA repair and indicates the feasibility of using this method for screening individuals for genetic deficits in DNA repair.


A simplified method for production and growth of multicellular tumor spheroids.

A new technique, based on the growth of tumor cells in liquid media over an agar base, has been developed for the formation and growth of multicellular tumor spheroids. All of the 11 transformed cell lines tested formed multicellular tumor spheroids, while none of the 8 normal cell types tested did so. The advantages of the present technique over older methods include its simplicity, generality, and experimental flexibility.


Survival and cure of leukemic mice after circadian optimization of treatment with cyclophosphamide and 1-beta-D-arabinofuranosylcytosine.

When cyclophosphamide and 1-beta-D-arabinofuranosylcytosine were administered to mice previously given injections of L1210 leukemia cells, the combination was more effective than either drug given alone. The effectiveness of the 2 drugs in combination was strongly influenced by the stage of the circadian system at which the drugs were administered. With the use of a chronobiological (sinusoidal) approach, in comparison with one or two  conventional treatment schedules, it was possible to demonstrate an overall lower toxicity as monitored by death or weight loss. In general, mean survival times and cures (when obtained) were circadian stage dependent; for example, in 1 study the cure rate was 94% in mice treated at 1 circadian stage, but only 44% in those treated at another stage. It cannot be overemphasized, however, that just as the "right" timing can enhance (with statistical significance) both the tolerance to chemotherapeutic agents and the rate of cure in leukemic mice, so can the "wrongly" timed (wrongly placed) ara-C sinusoid or "wrongly" timed cyclophosphamide enhance toxicity and host death rate.


Effects of phenobarbital and endotoxin on the lethality and metabolism of 6-mercaptopurine in male BALB/c mice.

In male BALB/c mice, a combination of individually non-lethal doses of 6-mercaptopurine and endotoxin was significantly lethal. In contrast, mice treated with phenobarbital were resistant to this lethal effect. The high levels of thioinosinic acid in mice that were treated with endotoxin contrasted significantly with the levels in phenobarbital-treated mice. On the other hand, the concentration of hypoxanthine was increased by the administration of phenobarbital and decreased by the administration of endotoxin. The sleeping time and levels of pentobarbital hydroxylase found in endotoxin-treated mice were consistent with the lethality and levels of thioinosinic acid. After mice were treated with endotoxin, their sleeping time was prolonged, which agrees with the course of the stimulatory effects of 6-mercaptopurine anabolism. However, there were no significant differences in hypoxanthine-guanine phosphoribosyltransferase. Furthermore, contrary to expectation, there were significant increases in xanthine oxidase after treatment with endotoxin. Thus, the metabolism of 6-mercaptopurine might be modified by hepatic microsomal enzyme activity.


Preoperative intralesional Bacillus Calmette-Guérin for mammary adenocarcinoma in rats.

The optimal time interval between intralesional Bacillus Calmette-Guérin (BCG) and resection of s.c. tumor was studied in 70 female Fischer rats implanted with syngeneic 13762 mammary adenocarcinoma. If this tumor is resected about 17 days after implantation, all animals die from spontaneous pulmonary metastasis. Injection of BCG to tumor 3 to 7 days before resection, significantly improved the survival rates over rats that had resection of tumor only. About 22% of the rats so treated are long-term cures. The therapeutic effect of intralesional BCG was most pronounced in rats with smaller tumors, although BCG was effective in tumors over 2 cm. Intralesional BCG given 1 day prior to resection decreased survival for rats bearing larger tumors. The addition of postoperative systemic (s.c.) BCG immunotherapy did not improve the beneficial effect of preoperative intralesional BCG and resection of primary tumor.


Cell cycle dependency of metastatic lung colony formation.

Exponentially growing FSA 1233 cells, one of the clones isolated from a mouse fibrosarcoma, were synchronized by fractionation according to cell size by centrifugal elutriation. Cells from each fraction were analyzed by flow microfluorometry to determine the stages of the cell cycle and were injected i.v. to determine lung colony-forming efficiency. In vitro plating efficiency of these cells was similar throughout the cell cycle except for a slight reduction at G2 + M. On the other hand, lung colony-forming efficiency showed marked cell cycle and cell size dependencies, being lowest at G1, highest at S, and declining slightly at G2.


Differential excision from DNA of the C-8 and N2 guanosine adducts of N-acetyl-2-aminofluorene by single strand-specific endonucleases.

Purified duck reticulocyte DNA was reacted in vitro with [9-14C]-N-acetoxy-N-acetyl-2-aminofluorene. Hydrolysis of the [14C]-N-acetyl-2-aminofluorene-modified DNA followed by Sephadex LH-20 column chromatography showed that 85% of the DNA-bound [14C]-N-acetyl-2-aminofluorene was N-(deoxyguanosin-8-yl)-N-acetyl-2-aminofluorene and 15% was 3-(deoxyguanosin-N2-yl)-N-acetyl-2-aminofluorene. When this modified DNA was incubated with the single strand-specific nuclease, S1, and the undigested fraction of the DNA was analyzed, there was preferential loss of the quanosine C-8 adduct from the DNA. Moreover, analysis of the nucleosides released by exposure of N-acetyl-2-aminofluorene-modified DNA to a single strand-specific nuclease from Neurospora crassa showed only the guanosine C-8 adduct in the supernatant fraction. These results suggest that, whereas the N-(deoxyguanosin-8-yl)-N-acetyl-2-aminofluorene adduct in DNA causes major conformational changes in the double-stranded helix and localized regions of denaturation, the 3-(deoxyguanosin-N2-yl)-N-acetyl-2-aminofluorene adduct does not cause major distortions of the native DNA structure.


Correlation of cell kinetic and clinical response to chemotherapy in disseminated neuroblastoma.

Mitotic and labeling indices of bone marrow tumor cells were determined from patients with disseminated neuroblastoma. Although pretreatment values were variable, the median indices indicated that only a small proportion of tumor cells were proliferating. The pretreatment indices could not be correlated with presenting clinical features or with the response to chemotherapy. Studies were repeated after 7 daily doses of cyclophosphamide (150 mg/sq m) and serially after Adriamycin (35 mg/sq m) given on Day 8. Changes in the mitotic and labeling indices during the first course of therapy could be directly correlated with the clinical response as evaluated after 4 months of induction chemotherapy. In all patients who attained a complete or partial remission, an increase in these indices was observed after 7 days of cyclophosphamide. If this increase was associated with an observed kinetic effect of Adriamycin in the G1, S, and G2 phases of the cell cycle, a complete remission was attained. If, following Adriamycin, kinetic evidence of an effect was not present in all three phases of the cell cycle, only partial remission was attained. No clinical response to therapy was observed in those patients in whom the mitotic index and labeling index did not increase after 7 days of cyclophosphamide.


Induction of hepatic aryl hydrocarbon hydroxylase in C57BL mice by ionizing radiation.

Inbred strains of C57BL mice were exposed to either 100, 500, or 1000 rads of whole-body irradiation. Another group of mice were given injections of 3-methylcholanthrene only, and a control group had no treatment. Forty-eight hr after treatment, the animals were killed and hepatic aryl hydrocarbon hydroxylase (AHH) activity was measured by spectrophotofluorometer. A comparison of hepatic AHH activity in treated and nontreated groups of mice showed that each treated group had a significantly increased AHH induction compared with the control group. Although radiation appeared to have a dose-related effect on AHH induction, the increase with dose level was not statistically significant.


alpha-Lactalbumin content of rat mammary carcinomas and the effect of pituitary stimulation.

Primary mammary carcinomas induced in nonlactating rats by 7,12-dimethylbenz(alpha)anthracene or methylnitrosourea contained alpha-lactalbumin (alphaLA) in quantities equal to or less than 10% of the amounts found in the parenchyma of the 5-day lactating gland. Only two of five transplantable mammary carcinomas contained alphaLA when growing in rats without hormonal stimulation. Hormonal stimulation maintained by transplantation into lactating females for 146 generations (65 months) failed to induce alphaLA production in dimethylbenz(alpha)anthracene no.1 transplantable mammary carcinoma. Transplantation of a pituitary gland under the kidney capsule of the host (a) increased alphaLA content of primary dimethylbenz(alpha)anthracene-induced mammary carcinomas, (b) reduced alphaLA content of primary methylnitrosourea-induced mammary carcinomas, and (c) was unable to modify the alphaLA levels in five transplantable mammary carcinomas.


Temporal acquistion of enhanced fibrinolytic activity by syrian hamster embryo cells following treatment with benzo(a)pyrene.

Following treatment of Syrian hamster embryo cells with benzo(a)pyrene, the time required for the expression of enhanced fibrinolytic activity was examined. For this study, the fibrin-agarose overlay method was developed to distinguish the activity of normal and transformed colonies of hamster cells. Colonies possessing enhanced fibrinolytic activity were not observed one passage (2 weeks after treatment). Morphologically transformed colonies, which exhibited no enhanced fibrinolytic activity, were observed 8 days following treatment. In contrast to these two early changes, cells capable of growth in soft agar were observed much later (6 to 8 weeks after treatment). Untreated Syrian hamster embryo cells generally senesced and did not exhibit enhanced fibrinolytic activity. Approximately 1 of 10 untreated cultures escaped senescence and evolved as a continuous cell line; such cultures frequently exhibited enhanced fibrinolytic activity. These results suggest that the acquisition of enhanced fibrinolytic activity, while perhaps not a cause of neoplastic transformation, may reflect a loss of control of the normal function of the cellular genetic apparatus during the process of transformation.


Metabolic disposition of antipyrine in patients with lung cancer.

The metabolism of antipyrine (10 mg/kg i.v.) was studied in nine patients with cancer of the lung and in a cancer-free control group matched for age, sex, drug intake, and smoking and drinking history. The mean plasma clearance of antipyrine was 0.0475 +/- 0.009 liter/kg/hr in the tumor group and 0.0557 +/- 0.007 liter/kg/hr in the control group (p greater than 0.05). The antipyrine plasma elimination half-life was longer in the group with tumors (9.5 +/- 1.3 hr) compared to the control group (7.7 +/- 1.3 hr), but the difference was not statistically significant (p greater than 0.05). There was no difference between the groups in the excretion of two major antipyrine metabolites, 4-hydroxyantipyrine and N-demethylantipyrine, in a 48-hr urine sample. Thus, the presence of lung cancer in humans does not significantly alter antipyrine elimination.


Secondary structural modifications as a consequence of in vitro acetylation and phenanthrylation of DNA by the ultimate carcinogen N-acetoxy-N-2-acetylaminophenanthrene.

The acetic acid ester of the proximate carcinogen N-hydroxy-N-2-acetylaminophenanthrene was reacted in vitro with native and heat-denatured calf thymus DNA under various conditions. We showed that besides the phenanthrylation of the DNA bases there is an acetylation reaction of the DNA during its reaction with the ultimate carcinogen. Heat-denatured DNA is 5 to 10 times more acetylated than native DNA. This result suggests that most of the acetylation sites are nonreactive in the double-helical structure of DNA. On the other hand, the phenanthrylation of the bases is shown not to depend on the DNA secondary structure, suggesting that the phenanthrylation sites of the bases are accessible in the grooves of the DNA double helix. The influence of the DNA dynamic structure on the reactions of acetylation and phenanthrylation has been investigated by increasing the ionic strength of the incubation buffer. The melting temperature of different DNA samples, which have been reacted with different concentrations of N-acetoxy-N-2-acetylaminophenanthrene, decreases as the extent of the DNA modifications increases. This thermal destabilization of the double helix is tentatively attributed to the phenanthrylation rather than to the acetylation reaction.


Immunosuppressive effects of 3-methylcholanthrene given intratracheally in various inbred strains of mice.

The immunosuppressive effects of 3-methylcholanthrene (MCA) given intratracheally have been shown to correlate with susceptibility of some inbred strains of mice to MCA-induced carcinogenesis. In susceptible strains of mice, C3Hf and C57BL/6, intratracheal administration of MCA resulted in profound systemic immunodepression. This effect was not observed in resistant DBA/2 mice. This immunodepressive effect correlated with the inducibility of the aryl hydrocarbon hydroxylase enzyme complex and the inducibility of pulmonary tumors by MCA.


Ornithine decarboxylase induction and DNA synthesis in hamster embryo cell cultures treated with tumor-promoting phorbol diesters.

The effects of tumor-promoting phorbol diesters on ornithine decarboxyalse (ODC) activity and DNA synthesis in normal and chemically transformed hamster embryo fibroblasts (HEF) in culture were studied. Only those phorbol diesters with promoting activity in mouse skin induced ODC in HEF. ODC was induced in both cell types by 12-O-tetradecanoyl-phorbol-13-acetate (TPA); maximal induction occurred 4 to 6 hr after the addition of the promoter to the medium of confluent cultures and was greater in transformed cells than in normal cells. The extent of induction in transformed cells treated with 0.016 to 1.6 micron TPA was dose dependent. The cellular concentrations of the polyamines, particularly putrescine, also increased after TPA treatment. The addition of TPA to confluent cultures of either normal or transformed HEF did not produce an increase in cell number or the percentage of [3H]thymidine- labeled nuclei and did not stimulate the incorporation of [3H]thymidine. ODC also was induced by adding fresh medium to the cultures. When both fresh medium and TPA were added, the effect of the medium was markedly potentiated in transformed, but not in normal, cells. These experiments demonstrate that tumor promoters specifically induce ODC in HEF without increasing the rate of DNA synthesis and that normal and transformed HEF differ in the levels of ODC activity attained after exposure to promoters.


Inhibition of target cell mitosis as a measure of the cytostatic effects of activated macrophages on tumor target cells.

Studies were carried out in vitro that showed that activated macrophages inhibited tumor target cells from undergoing mitosis. With the use of target cells synchronized in the mitosis phase of the cell cycle, this manifestation of macrophage-mediated cytostatic effects was preceded by the complete inhibition of target cell DNA synthesis as measured by incorporation of [3H]thymidine.


Influence of  a chronic environmental stress on the incidence of methylcholanthrene-induced tumors.

The influence of a chronic environmental stress, living in a 2 degrees environment, on the incidence of methylcholanthrene-induced tumors in albino female Simonsen rats, a Sprague-Dawley-derived strain, was studied. The results indicated that the metabolic rate was double for rats kept at 2 degrees, compared with those kept at 25 degrees. Exposure to 2 degrees for life, with no other treatment, reduced median life expectancy to 560 days compared with 686 days for rats kept at 25 degrees. Transfer to a 2 degrees environment after 250 days at 25 degrees reduced the incidence of spontaneous tumors, while transfer to 25 degrees after 250 days at 2 degrees increased the incidence of tumors compared to that for rats always kept at 25 degrees. Exposure to an environmental temperature of 2 degrees immediately following a carcinogenic stimulus (3-methylcholanthrene, 2 mg s.c.) significantly reduced the incidence of tumors compared to that in rats kept at 25 degrees but did not change tumor induction time. The reduced tumor incidence may have resulted from inhibition of the carcinogenic transformation by chronic stress. The survival time of rats with 3-methylcholanthrene induced tumors was not significantly less in a 2 degrees environment than it was at 25 degrees.


Mechanism of tumor cell resistance to lysis by syngeneic lymphocytes.

B16 melanoma variant lines, which resisted lysis by syngeneic lymphocytes, were selected in vitro by repeated exposure of the tumor cells to purified cytotoxic lymphocytes. The resistance of the tumor cells to lysis mediated by syngeneic lymphocytes was not accompanied by a loss or masking of major histocompatibility antigens. Neither the lymphocyte-susceptible B16 (F10) nor the lymphocyte-resistant B16 (F10Lr) cells grew in allogeneic recipients, and both were destroyed in vitro by allogeneic lymphocytes. The resistance to lysis by syngeneic lymphocytes was not accompanied by loss or masking of receptors for macrophage recognition and destruction. F10Lr cells did not protect F10 cells from lymphocyte-mediated lysis in cocultivation experiments. Immunization of syngeneic mice in vivo with B16-F10 cells successfully protected mice against challenge with B16-F10 cells. However, mice immunized with B16-F10Lr cells were not protected against challenge with B16-F10 cells. B16-F10Lr cells were not immunogenic when tested under this condition. Light, scanning, and transmission electron microscopic studies of tumor cell-lymphocyte interaction suggested that the resistance of B16-F10Lr cells to destruction by syngeneic lymphocytes in vitro was due to the masking or absence of tumor-specific antigen(s) present on the lymphocyte-susceptible F10 cells.


Ultrastructural comparison between cultured and tumor cells of human malignant melanoma.

Tumor cells from 28 human malignant melanomas were compared by electron microscopy with cultured cells of 17 established human melanoma cell lines derived from the same types of tumors. Both tumor and cultured cells were classified into five types according to their different fine-structural characteristics. There was a correlation between the cell types observed in the tumor fragments and in the cell lines. This evidence suggests that cultured human melanoma cells retained in vitro the characteristics of the melanoma cells in vivo, from which they were derived.


Disposition of 5-fluorouracil after intravenous bolus doses of a commercial formulation to cancer patients.

A high-pressure liquid chromatographic method that is used to determine the pharmacokinetic disposition of 5-fluorouracil from the plasma compartment is presented. The method requires only 0.5 ml of plasma for each determination and is sensitive to 0.1 mg of drug per liter. Novel methodology with the use of an ion-specific electrode technique for the determination of urinary excretion kinetics of 5-fluorouracil and its metabolites is also presented. This study demonstrated a much greater variability for the disposition of 5-fluorouracil by cancer patients than has been reported previously. The apparent volume of distribution for this drug varied more than 37-fold. Its plasma half-life varied more than 19-fold, and its urinary excretion half-life varied almost 400-fold. These data are compatible with the hypothesis that this variation could account, at least in part, for the variable therapeutic and toxic response to 5-fluorouracil. The methodology presented in this study is sufficiently simple and sensitive to allow assessment of this hypothesis by investigating cancer patients who receive therapeutic doses of 5-fluorouracil.


Method for quantitating tumor cell removal and tumor cell-invasive capacity in experimental metastases.

An improved method is presented for analyzing the decay of i.v.-injected labeled tumor cells in the lung. A simple compartment analysis yields quantitative values for (a) the rate at which tumor cells are lost or cleared from the lung, and (b) the "invasion" rate at which tumor cells colonize the interstitial space. Statistical methods are outlined for testing the significance of the contribution of each rate to the overall shape of the decay curve and for testing whether or not a given rate is altered significantly during an experiment. The usefulness of the method is demonstrated in analysis of experiments involving perturbations of the host or of the injected tumor cells.


Variants of a human colon adenocarcinoma cell line which differ in morphology and carcinoembryonic antigen production.

A variant, HCT-8R, of the colon adenocarcinoma cell line HCT-8 was located and cloned. The variant and parent cell line were characterized with respect to morphology, growth characteristics, karyotype, production of Cea, and ability to form tumors in nude mice. The variant cells differed from the parent cells in morphology, marker chromosomes, and ability to form colonies in soft agar and produced more carcinoembryonic antigen. The two cell strains were equally oncogenic in nude mice, although HCT-8R cells produced poorly differentiated tumors while HCT-8 cells produced tumors with both differentiated and poorly differentiated areas. Thus, in nude mice, no correlation was observed between carcinoembryonic antigen production by cells and their oncogenicity.