Showing papers by "Montreal Children's Hospital published in 1976"

A continuous tumor-cell line from a human lung carcinoma with properties of type II alveolar epithelial cells.

Abstract: The A549 tumor-cell line, initiated from a human alveolar cell carcinoma, has been continuously propagated in vitro for more than 3 years (more than 1,000 cell generations). These cells have a human karyotype and appear to have been derived from a single parent cell. All A549 cells examined by electron microscopy at both early and late passage levels contain multilamellar cytoplasmic inclusion bodies typical of those found in type II alveolar epithelial cells of the lung. At early and late passage levels, the cells synthesize lecithin with a high percentage of disaturated fatty acids utilizing the cytidine diphosphocholine pathway; such a pattern of phospholipid synthesis is expected for cells believed to be responsible for pulmonary surfactant synthesis. The A549 cell line should permit in vitro analysis of human surfactant synthesis and secretion and possibly provide a source of human surfactant for therapeutic intervention in pulmonary disease states characterized by surfactant deficiency.

Assessment of a cognitive training program for hyperactive children.

Abstract: Modeling, self-verbalization, and self-reinforcement techniques were used to train hyperactive children in more effective and less impulsive strategies for approaching cognitive tasks, academic problems, and social situations. Eighteen hyperactive children took part in the training program. The control group, which received no training, consisted of 11 children, matched with the experimental group on age, IQ, and measures of hyperactivity and impulsivity. Several tests and measures, some of which have been shown to differentiate between hyperactive and normal children, were administered prior to training, at the end of the 3- month training period, and after a further 3- month period in which no training took place. The trained group showed significantly greater improvement on several of the measures, both at the time of posttesting and on the follow-up evaluation.

The multifactorial/threshold concept -- uses and misuses.

Abstract: The common congenital malformations have familial distributions that cannot be accounted for by simple Mendelian models, but can be explained in terms of a continuous variable, "liability," with a threshold value beyond which individuals will be affected. Both genetic and environmental factors determine liability, making the system multifactorial. Cleft palate is a useful experimental model, illustrating a number of factors that contribute to palate closure, the nature of a developmental threshold, and how genes and teratogens can alter the components of liability to increase the probability of cleft palate. The nature of the genetic component to liability in human malformations in not clear, and various possibilities, ranging from polygenic in the strict sense to a major gene with reduced penetrance are compatible with the data -- but the important feature is the threshold. Much of the confusion over the concept results from inconsistent use of terminology. The term "multifactorial" should be used for "determined by a combination of genetic and environmental factors," without reference to the nature of the genetic factor(s). "Polygenic" should be reserved for "a large number of genes, each with a small effect, acting additively." When several genes, with more major effects are involved, "multilocal" can be used. When it is not clear which of these is applicable the term "plurilocal" is suggested, in the sense of "genetic variation more complex than a simple Mendelian difference." Since teratological data often represent threshold characters the concept also has important implications for the interpretation of data on dose-response curves, synergisms, and strain differences in response to teratogens.

Human pancreatic islets in culture: effects of supplementing the medium with homologous and heterologous serum

Abstract: Islets of Langerhans, isolated from the human fetal pancreas and cultured in media supplemented with serums from human umbilical cord or adult donors, remained intact, free-floating, and functional for 2 to 5 months. Substitution of fetal calf serum for the human serum usually resulted in attachment of islets, monolayer formation, and relatively early (3 weeks) functional arrest.

Insulin responses during catch-up growth of infants who were small for gestational age.

Abstract: Growth characteristics of 15 full-term infants, selected because of weights more than 2 SD below the mean for gestational age, are described. The response to an intravenous injection of glucose was utilized to measure the insulin response of the infants at 6 months. Infants small for gestational age grow at a faster rate than appropriate-for-age infants during the first six months of life. There was a positive correlation between the growth velocity of the period and insulin release and a negative correlation between growth velocity and birth length. There was no correlation between these variables and increases in weight during the same period. Growth velocity during catch-up growth is related to the degree of preceding retardation but insulin may play a permissive role.

Developmental aspects of glutathione S-transferase B (ligandin) in rat liver.

Abstract: The postnatal development in male Sprague-Dawley rats of hepatic glutathione S-transferase B (ligandin) in relation to the other glutathione S-transferases is described. The concentration of glutathione S-transferase B in 1-day-old male rats is about one-fifth of that in adult animals. The enzyme reaches adult concentrations 4-5 weeks later. When assessed by substrate specificity or immunologically, the proportion of transferase B relative to the other glutathione S-transferases is high during the first week after birth. At this age, 67.5% of the transferase activity towards 1-chloro-2,4-dinitrobenzene is immunoprecipitable by anti-(transferase B), compared with about 50% in adults and older pups. Between the second and the fifth postnatal week, the fraction of transferase B increases in parallel fashion with the other transferases in hepatic cytosol. Neither L-thyroxine nor cortisol induce a precocious increase in glutathione S-transferase activity. Phenobarbital did induce transferase activity towards 1-chloro-2,4-dinitrobenzene and 1,2-dichloro-4-nitrobenzene in both pups and adults. The extent of induction by phenobarbital was a function of basal activity during development such that the percentage stimulation remained constant from 5 days postnatally to adulthood.

Alpha-tocopherol: its inhibition on human platelet aggregation.

Abstract: Alpha-tocopherol inhibits human platelet aggregation induced by arachidonate sodium, collagen, epinephrine, adenosine diphosphate or thrombin — arachidonate sodium being the most susceptible. The second phase of the biphasic platelet aggregation induced by epinephrine or adenosine diphosphate is preferentially inhibited.

A sex difference in hepatic glutathione S-transferase B and the effect of hypophysectomy.

Abstract: The glutathione S-transferases are a group of proteins with overlapping substrate specificities and ligand-binding capacities. This report examines certain approaches to the measurement of transferase B (ligandin) in the rat liver. The ratio of catalytic activities toward 1-chloro-2,4-dinitrobenzene and 1,2-dichloro-4-nitrobenzene gives some indication of the relative proportions of the various transferases present in 100 000 g supernatants. The fraction of catalytic activity towards 1-chloro-2,4-dinitrobenzene, due to transferase B, was best measured by immunoprecipitation with anti-(transferase B). Male rat liver exhibited three times more activity towards 1,2-dichloro-4-nitrobenzene than female tissue; however, the activities towards 1-chloro-2,4-dinitrobenzene were almost identical. By assuming a specific activity of 11 mumol/min per mg, immunoprecipitable transferase B comprised 4.5 +/- 0.2% of total protein in the 100 000 g supernatant of female rat liver, and 70% of the transferase activity towards 1-chloro-2,4-dinitrobenzene. The amount of transferase B in the 100 000 g supernatant from male rat liver is significantly lower with respect to both fraction of total protein (3.3 +/- 0.2%) and overall transferase activity towards 1-chloro-2,4-dinitrobenzene (48%). Hypophysectomy eliminated this sex difference in the hepatic concentration of glutathione S-transferase B.

Activity of Newer Aminoglycosides and Carbenicillin, Alone and in Combination, Against Gentamicin-Resistant Pseudomonas aeruginosa

Abstract: The in vitro activity of the aminoglycoside antibiotics tobramycin, sisomicin, amikacin, gentamicin, and netilmicin (SCH 20569) were compared against 26 gentamicin-resistant isolates of Pseudomonas aeruginosa cultured from hospitalized children. Tobramycin had the greatest activity on a weight basis, followed by sisomicin, gentamicin, amikacin, and netilmicin. All isolates were resistant to achievable concentrations of netilmicin and gentamicin, but 23% were inhibited by achievable concentrations of tobramycin, 8% by amikacin, and 4% by sisomicin. The combinations carbenicillin/tobramycin, carbenicillin/sisomicin, and carbenicillin/amikacin were synergistic for 92% of strains; antagonism was not encountered. These in vitro results suggest that tobramycin, sisomicin, or amikacin in combination with carbenicillin would be the safest initial regimen in the therapy of gentamicin-resistant Pseudomonas infections pending susceptibility studies.

The effect of acetylsalicylic acid on tsh and prl secretion after trh stimulation in the human

Abstract: In order to study the effect of prostaglandins on TSH release in the human, Acetylsalicylic Acid was given to 9 normal subjects at doses necessary to obtain a salicylate level of 20 mg/dl. TRH, 400 μg was injected prior to and after the medication. Thyroid hormone parameters were measured at time 0, and TSH and PRL at time 10, 20, 30, 45 minutes after the injection. The free fraction of thyroid hormones remained constant during treatment but a significant decrease of TSH concentration (30%) was noted after TRH injection on Acetylsalicylic Acid treatment whereas no changes were noted for PRL. As noted in the animal, this study indicates that in the human, prostaglandins potentiate the effect of TRH on TSH liberation by the pituitary where it has no effect on PRL.

Nasopharyngeal cancer in Bermuda.

Abstract: Six cases of nasopharyngeal carcinoma (NPC) were diagnosed in residents of Bermuda in the 7-year period 1966–1972. While epidemiologic study revealed no history of common environmental exposures, two of the six cases occurred in adult sibs from a family in which a third adult sib developed NPC in 1963. These three cases were from a large, possibly in-bred Portuguese family with origins in the Azores Islands. The remaining four cases were all in black children ages 10–15; two of these four were first cousins. These observations suggest the possibility that genetic influence may contribute to the etiology of NPC.

Deletion of the short arms of chromosome 20.

Abstract: A 46, XX, del(20) (p11) karyotype (Paris Conference, 1971) was identified in an 11-month-old French-Canadian girl with a dysmorphic syndrome, multiple congenital anomalies, psychomotor and growth retardation. Both parents had normal phenotype and karyotype.

Genetics: voyage of discovery for Everyman. (Presidential address to the Society for Pediatric Research, April 29, 1976, St. Louis, Missouri).

Abstract: Genetics: Voyage of Discovery for Everyman: (Presidential Address to The Society for Pediatric Research, April 29,1976, St. Louis, Missouri)

English reading within the french immersion program: a comparison of the effects of the introduction of english reading at different grade levels

Abstract: The focus of the study was the French immersion program in Quebec, in which English reading is introduced in some schools at the Grade 2 level, and in some at the Grade 3 level. The hypothesis that delaying the introduction of reading in English until Grade 3 would improve English reading skills was tested. The stage at which English reading was first taught was found not to affect reading grade level as measured by an individual reading test. Reasons were discussed for the final recommendation that English reading be delayed until Grade 3.

Reevaluation of the Disk Diffusion Method for Sulfonamide Susceptibility Testing of Neisseria meningitidis

Abstract: Lack of correlation between quantitative minimal inhibitory concentration (MIC) determinations and disk diffusion susceptibility tests in our laboratory prompted a study to reevaluate the use of the disk diffusion test for sulfonamide susceptibility testing of Neisseria meningitidis. One hundred and sixty-three recent clinical isolates of N. meningitidis were examined for sulfonamide susceptibility by the agar dilution and disk diffusion methods. Optimal inocula for each of the tests were determined, and thereafter all disk diffusion tests were compared with quantitative MICs as determined by the agar dilution method using sulfadiazine and an inoculum of 10(6) colony-forming units (CFU)/ml. The clearest and most reproducible zone diameters were obtained with a 10(7)-CFU/ml inoculum in the disk diffusion test. There was complete correlation between the disk zone diameters for 300-mug disks of sulfadiazine and sulfathiazole and the agar dilution test MICs. All isolates with a zone diameter of /=30 mm were susceptible. False susceptible and false resistant readings were obtained with 300-mug sulfisoxazole disks. These data suggest that inocula and type of sulfonamide are critical factors in the disk diffusion test for meningococcal susceptibility testing. Sulfonamide disks are not interchangeable for susceptibility testing of meningococci.

An approach to the treatment of an adolescent with ulcerative colitis. Conjoint therapy of the parents.

Abstract: Summary The pertinent literature on the psychopathology and psychotherapy of individuals with ulcerative colitis is briefly summarized. A particular problem encountered in clinical practice is then described and an approach to its solution is detailed. A 14-year-old, middle-class girl had experienced exacerbations of ulcerative colitis over two years. Without her agreement, she was referred for psychiatric assessment by a gastroenterologist when he found that she was not cooperating with medical treatment, and when she appeared depressed. On assessment, the patient was found to be a silent adolescent whose main symptoms were indicative of immaturity, shyness and anger. This was understood in terms of the overprotective, domineering mother, a protective father and even a protective brother. The therapeutic problem was outlined on referral by her reluctance to take medication, to see doctors or to “let her friends know” of her illness. The patient and the family interactions are described. Confronted by a girl whose denial was of such proportions it became clear that individual psychotherapy could not begin. There was no motivation and no contract to work towards this goal, and there was excessive resistance. With the girl's refusal to become involved in family therapy, it was decided that both parents should review their respective parenting roles in conjoint therapy. This had as its goal the provision of a more stimulating opportunity for the growth and development of the patient. The author describes in detail the assessment and treatment, which was conceptualized as occurring in two stages. Stage one was an attempt at individual therapy and at developing a therapeutic alliance, both of which were unsuccessful. The second stage, conjoint therapy of the parents took place, and provided a more fruitful outcome.

A Community Occupational Therapy Summer Program for Children

Abstract: This article describes a pilot project in which eleven out-patients of the Occupational Therapy Department at the Montreal Children's Hospital were integrated into a summer day camp of a local YMCA. The objectives of this program are outlined, as well as the actual description of the camp program. An evaluation of the project examines the results of a questionnaire administered to the subjects' parents before and after the camp experience as well as a discussion of some additional advantages and disadvantages observed in the program. It appears that there are many indications for screening and treating children in the community, and that providing occupational therapy services to children in their natural milieu may be of significant benefit to the child. It is suggested that the integration of occupational therapy in the community be carried out permanently and extensively and that such programs deserve further study.