A study of a Self-Care Rehabilitation Program in pediatric asthma

The Self-Care Rehabilitation in Pediatric Asthma (SCRPA) project was designed to ascertain the level to which children with asthma are able to acquire the asthma knowledge and skills presented in a self-management training program conducted by the American Lung Association of Utah and the effect of such training on the asthma experience. The preschool SCRPA Curriculum (ages 2-5) consisted of six 1-hour classes scheduled twice a week for 3 weeks. The first and last classes were for one or both parents only, and the middle four sessions were for the child and parent(s). The school-age SCRPA curriculum (ages 6-14) consisted of eight 90-minute classes for both child and parent(s) scheduled twice a week for 4 weeks. Private physicians referred 21 preschool children and 38 school-age children into the program. The school-age children were randomly assigned to a study or control group, and the preschool children served as their own controls. A comparison of asthma episodes during the 3 months before and after training showed a statistically significant decrease in the number of episodes but no change in severity in the preschool, school study, and school control groups. The decrease in episodes for the control groups suggest that the family record keeping required of all subjects may have a beneficial effect, a phenomenon worth further investigation. Also, the school-age group, in pre- and posttesting, demonstrated that the SCRPA curriculum increased knowledge and skills in the study group, changes not found in the control group.

Processing of the intron-containing thymidylate synthase (td) gene of phage T4 is at the RNA level

The interrupted T4 phage td gene, which encodes thymidylate synthase, is the first known example of an intron-containing prokaryotic structural gene. Analysis of td-encoded transcripts provides evidence in favor of maturation at the RNA level. Northern blotting with T4 RNA and with region-specific probes revealed three classes of RNA: diffuse premessage (ca. 2.5 kb), a low-abundance mature mRNA (ca. 1.3 kb), and an abundant free intron RNA (ca. 1.0 kb). The existence of covalently joined mature mRNA was suggested by hybridization and S1 protection experiments and was confirmed by primer extension analysis of the splice junction. In analogy to expression of interrupted eukaryotic genes, these results are consistent with an RNA processing model that would account for the direct gene transcript serving as precursor for both free intron RNA and a spliced mRNA that is colinear with the thymidylate synthase product.

A study of angiogenesis factors from five different sources using a radioimmunoassay

The use of a radioimmunoassay (RIA) demonstrated that angiogenic factors from human and animal tumours, normal bovine retinas, myocardial infarcts, synovial fluid from patients with joint diseases and wound fluid shared common antigenic determinants. Values for angiogenesis factors expressed as microgram Walker tumour TAF/mg protein varied from 0.8 (wound fluid) to 207 (myocardial infarct). Activated macrophages produced an angiogenic factor which did not cross-react. Normal tissue extracts which were non-angiogenic by the chicken chorioallantoic membrane assay also failed to cross-react in the RIA. The antigenic similarity of angiogenic factors from such a wide variety of sources suggests that, in order to minimize therapeutic side effects, it would be best to use angiogenic agonists and antagonists locally.

Flavone modulators of rat hepatic aryl hydrocarbon hydroxylase

The cytochrome P-450-dependent aryl hydrocarbon hydroxylase (AHH) metabolizes a wide variety of endogenous and exogenous compounds to nontoxic metabolites and/or toxic products. We have utilized a series of 18 flavone modulators of AHH to distinguish and probe for different cytochrome P-450 isozymes in liver microsomes from control and 3-methylcholanthrene (MC)-injected rats. some flavones (maackiain acetate, flavanone, mollisacacidin, embinin, sciadopitysin) activated, while most of the tested compounds inhibited the MC-induced type of AHH. Although all flavones either inhibited or had little effect on the constitutive AHH in microsomes from control rats, the degree of inhibition varied greatly: some flavones (chrysin, chrysoeriol, baicalein, maackiain acetate, isoliquiritigenin, sciadopitysin) inhibited over 75% of the AHH. The various flavones we screened may prove useful in defining the cytochrome P-450 content of tissues and for probing the active sites of individual isozymes. The modulatory effects of the naturally occurring flavones assume additional importance in that they may be factors in animal and human responsiveness to cytochrome P-450 substrates.

Specificity of medicarpin and related isoflavonoids in inhibition of rat hepatic mixed function oxidase activity

The cytochromes P-450 of the mixed function oxidase system metabolize a wide variety of endogenous compounds to either nontoxic products or toxic metabolites. A number of natural products, such as flavonoids, influence this metabolism. Exposure to these compounds may therefore be a factor in animal and human responsiveness to cytochrome P-450 substrates. We have examined the effect of the pterocarpan medicarpin on the cytochrome P-450-dependent aryl hydrocarbon hydroxylase (AHH) and ethoxycoumarin deethylase (ECD) activities of rat liver microsomes. Medicarpin and maackiain and two of their biosynthetic precursors inhibit the constitutive and phenobarbital (PB)-induced types of AHH, but have little effect on the 3-methylcholanthrene (MC)-induced type of AHH. This is in contrast to the effect of the commonly used cytochrome P-450 inhibitor 7,8-benzoflavone, which inhibits the hepatic AHH of MC-treated rats and has no effects on the AHH of control or PB-treated rats. However, medicarpin inhibited the constitutive as well as the PB- and MC-induced ECD. The specific modulatory effect as well as its relative availability suggests the utility of medicarpin as a probe for different forms of cytochrome P-450 in animal tissues.

Monoclonal antibody phenotyping of interindividual differences in cytochrome P-450-dependent reactions of single and twin human placenta

Cytochromes P-450 are a family of enzymes responsible for metabolism of drug and xenobiotics, such as carcinogen, and certain physiological compounds, such as steroids and prostaglandins. We prepared a monoclonal antibody (MAb 1-7-1) to a polycyclic hydrocarbon-induced rat cytochrome P-450 that antigenically defines and inhibits a type of cytochrome P-450 responsible for aryl hydrocarbon hydroxylase (AHH) and 7-ethoxycoumarin deethylase (ECD) activity in human placenta. We examined the placentas from single and twin births from mothers who smoked cigarettes and nonsmokers. The MAb 1-7-1 inhibited the smoking-induced AHH activity of essentially the entire population of placentas by 70 to 95%. Thus, up to 95% of the AHH in a population of human placentas is catalyzed by a type of cytochrome P-450 that contains an antigenic site recognized by MAb 1-7-1. A second type of cytochrome P-450, which is insensitive to MAb 1-7-1, is responsible for the ECD activity in the placentas of nonsmokers. In the placentas from smokers, both types of P-450 contribute to ECD activity. Their ratios can be determined by the amount of inhibition by MAb 1-7-1 which ranges from 0 to 70%. The placentas from both dizygotic and dichorionic monozygotic twins show extraordinarily high intrapair concordance for both the absolute amounts of AHH and ECD and their inhibition by MAb 1-7-1 compared with unrelated individuals, indicating that interindividual differences in these parameters of biological activity are not due to random variation or experimental error. Our results show that the amount of activity of antigenically unique types of cytochrome P-450 responsible for different drug and carcinogen reactions can be measured in different individuals by the amount of their inhibition by highly specific monoclonal antibodies. These findings may have general application to studies on the relationship cytochrome P-450 phenotype to population differences in drug and carcinogen biotransformation.

Monoclonal antibody-directed phenotyping of cytochrome P-450-dependent aryl hydrocarbon hydroxylase and 7-ethoxycoumarin deethylase in mammalian tissues

The distribution of cytochromes P-450 that catalyze aryl hydrocarbon hydroxylase and 7-ethoxycoumarin O-deethylase were studied with monoclonal antibody (MAb) 1-7-1 which completely inhibits these activities of a purified 3-methylcholanthrene-induced rat liver cytochrome P-450. The degree of inhibition by MAb 1-7-1 quantitatively assesses the contribution of different cytochromes P-450 in the liver, lung, and kidney microsomes from untreated, 3-methylcholanthrene- and phenobarbital (PB)-treated rats, mice, guinea pigs, and hamsters. Enzyme sensitivity to MAb 1-7-1 inhibition defines two types of cytochrome P-450 contributing to aryl hydrocarbon hydroxylase and 7-ethoxycoumarin O-deethylase. The MAb 1-7-1-sensitive cytochrome P-450 is a major contributor to aryl hydrocarbon hydroxylase in rat liver, lung, and kidney of 3-methylcholanthrene-treated rats, C57BL/6 mice, guinea pigs, and hamsters; this type is also present in lesser amounts in the extrahepatic tissues of the control and PB-treated animals, and in the lungs of the relatively "noninducible" DBA/2 mice treated with 3-methylcholanthrene. This form however makes little or no contribution to liver aryl hydrocarbon hydroxylase of control or PB-treated animals. 7-Ethoxycoumarin O-deethylase is also a function of both the MAb 1-7-1-sensitive and insensitive classes of cytochrome P-450. The ratio of the classes contributing to aryl hydrocarbon hydroxylase and 7-ethoxycoumarin O-deethylase differs in the various tissues and species and after inducer treatment. All of the 7-ethoxycoumarin O-deethylase activity in guinea pigs and hamsters is a function of cytochromes P-450 different than the MAb 1-7-1-sensitive cytochrome P-450 responsible for aryl hydrocarbon hydroxylase activity. Thus, the MAb 1-7-1 antigenically defines the type of cytochromes P-450 contributing to each reaction. Cytochromes P-450 can be viewed as paradigmatic for enzyme systems in which the nature and amount of product is regulated by multiple isoenzymic forms. Analyses using monoclonal antibodies to specific isoenzymes may thus have broad application to a variety of other complex systems which are composed of multiple isoenzymes.

A problem in the radiochemical assay of glucose-6-phosphatase in muscle

A radiochemical assay for glucose-6-phosphatase, which depends on the absorption of radiolabelled substrate on to a nascent precipitate of BaSO4 and Zn(OH)2, can give rise to erroneously high activities. Adsorption on to a Fe(OH)3 precipitate does not expose the incubation medium to extreme alkaline conditions and provides a satisfactory and simple assay. This method demonstrates a very low activity of the enzyme in mammalian muscle, in contrast with previous findings.

Design and methods in a multi-center case-control interview study

We conducted a case-control study in ten areas of the United States in which a total of 2,982 bladder cancer patients and 5,782 population controls were interviewed. We employed a variety of existing and new techniques to reduce bias and to monitor the quality of data collected. We review here many of the design elements and field methods that can be generally applied in epidemiologic studies, particularly multi-center interview studies, and explain the reasons for our selection of the methods, instruments, and procedures used.

Human lung tumour cell line adapted to grow in serum-free medium secretes angiogenesis factor

A human lung tumour cell line has been grown in serum-free medium for 12 months and during this period cells were subcultured every 4 days. The culture medium contained an angiogenesis factor which has been purified and shown to be similar to that isolated from other sources including solid tumours. This is the first report that demonstrates de novo synthesis and secretion of angiogenesis factor by a cell line adapted to grow in a serum-free medium.

Rectalepidural fistula complicating Crohn's enterocolitis

A previously unreported complication of a patient with Crohn's enterocolitis and internal fistulation is presented. The patient presented with meningeal signs in the lumbosacral region, fever, and sepsis. Computerized axial tomography revealed air in the epidural space, and a presumptive diagnosis of rectalepidural fistula was made. Surgical management included a diverting end sigmoid colostomy and presacral drainage.

Angiogenesis factor from human myocardial infarcts

5 of 8 infarcted human myocardial tissues were shown to contain an angiogenesis factor which resembles that obtained from solid tumours. The concentration of angiogenesis factor, measured by radioimmunoassay, was similar to that in tumours. It is suggested that the myocardial-infarct angiogenesis factor modulates collateral enlargement or ingrowth of new blood vessels in the infarcted tissues.

Phenotyping of cytochromes P-450 in human tissues with monoclonal antibodies

Cytochrome P-450 (P-450)-dependent aryl hydrocarbon hydroxylase (AHHase) and 7-ethoxycoumarin deethylase (ECDEtase) in human tissues were differentially inhibited by monoclonal antibodies (MAbs) that were prepared to inhibit and completely inhibited the activity of 3-methylcholanthrene-induced rat liver P-450. The AHHase and ECDEtase of placentas from individual women who smoked were inhibited by the MAbs by 83-90% and by 34-74%, respectively. Benz[a]anthracene (BaA)-induced AHHase and ECDEtase in lymphocytes were inhibited 18-65% and 30-78%, respectively. The enzymes in both control and BaA-induced human cells in culture were inhibited to different extents. Both the AHHase and ECDEtase in control and BaA-induced monocytes and in normal liver were largely unaffected by the MAb. Thus, we have with the MAbs: (i) identified P-450s with a common antigenic site in placenta, lymphocytes, and human cells in culture; (ii) identified two forms of hydrocarbon-induced P-450s in lymphocytes, at least one of which is common with the induced P-450s of placenta and with a P-450 form present in uninduced lymphocytes; (iii) identified two forms of P-450 responsible for smoking-induced ECDEtase activity in placenta, one of which is also responsible for AHHase activity; (iv) shown that the P-450s of liver, basal, and BaA-induced monocytes are different from the MAb-sensitive P-450s of placenta and lymphocytes; (v) quantitated in several human tissues the percentages of control and inducible AHHase and ECDEtase that are dependent on the MAb-sensitive P-450; and (vi) defined by HPLC the contribution of the MAb-sensitive P-450 to the formation of specific benzo[a]-pyrene metabolites. The results demonstrate the value of MAbs for defining antigenic site relatedness for different enzymatic functions of P-450s and for identifying and quantifying the amount of a specific enzyme activity in a tissue dependent on specific P-450s. This study may be a prototype for the use of MAbs for phenotyping and mapping of P-450s responsible for specific metabolic reactions and, thus, may be useful in determining the relationship of P-450 phenotype to individual differences in drug metabolism and carcinogen susceptibility.

Irritant contact dermatitis from an ornamental Euphorbia

An ornamental succulent plant sold in many plant stores in the Chicago area has been identified as Euphorbia hermentiana Lem. Open and closed patch testing using undiluted latex from this species was performed on five Caucasian volunteers. Open testing on flexor forearms resulted in irritant follicular dermatitis, while closed testing to the flexor surfaces of both upper arms in each subject produced bullae and vesiculation with residual desquamation and hyperpigmentation. Dermatological signs persisted for over a week following latex application.

Genital cancer in wives of penile cancer patients

We identified the wives or ex-wives of 227 males of the 256 reported with cancer of the penis to the New York State Cancer Registry from Upstate New York from 1960-64. Utilizing the Registry, death certificates, hospital and physician records, we ascertained those wives who developed cancer at any site from 1951-1975. We generated expected numbers of cases of cancer at each site by applying the age specific incidence rates experienced by women of a specific age in a specific year designated by the age of the wife of the index case in each year, estimating withdrawals from age-specific death rates. Thus, our expected numbers are based on the experience of the women in Upstate New York with traits like those of spouses of the men in the same population with cancer of the penis. We found significantly more cases of cancer of the cervix than expected. This was not true for other sites of cancer.