Production and characterization of monoclonal antibodies to Ha-ras and N-ras p21

The mammalian ras family consists of the Ha, Ki and N-ras genes that encode a series of 21,000 dalton proteins (p21). The three ras proteins participate in normal cell physiology and have been implicated in cellular transformation by either overexpression of the normal p21 or by mutation at positions 12, 13, or 61. To help understand the biological roles of the different ras proteins, we have generated monoclonal antibodies (Mabs) to the Ha-ras and N-ras p21. Mab Ha-770, raised to a Ha-specific synthetic peptide, reacts with Ha-ras recombinant p21 (r-p21) as well as cellular Ha-ras p21 by immunoprecipitation. Western blot and sandwich ELISA assays. Mab N-838, raised to an N-ras specific synthetic peptide, reacts with the N-ras recombinant p21 by immunoprecipitation, Western blot and sandwich ELISA assays. Mabs to the Ha-ras and N-ras p21 should be valuable reagents in assessing the individual roles of ras proteins in normal and neoplastic cells.

Fetal umbilical artery velocity waveforms and subsequent neonatal outcome

Flow velocity waveforms (FVWs) from the fetal umbilical artery were recorded from 2178 pregnant women over a 6-year period. All of them had an obstetric factor indicating increased risk of fetal compromise. A total of 6749 studies was recorded. The systolic diastolic (AB) ratio was measured and classified as normal (less than 95th centile), elevated (95-99th centile), high (greater than 99th centile) or extreme (absent diastolic flow). The results of these studies have been related to subsequent fetal and neonatal outcome. An abnormal umbilical artery FVW was associated with shorter gestation and infants with lower birthweight, shorter length and lower ponderal index. There was a highly significant association between an abnormal FVW and the birth of an infant small for gestational age. The significance of the association increased with the increased abnormality of the umbilical artery FVW and this was independent of gestational age. Preterm infants associated with high or extreme AB ratios spent twice as long in the neonatal nursery than those with normal AB ratios. Analysis of 794 pregnancies studies serially indicated that an abnormal FVW in which the AB ratio was increasing, in contrast to a decreasing AB ratio, predicted a poor outcome for both size at birth and duration of neonatal intensive care. We conclude that in high risk pregnancy Doppler umbilical artery FVW studies predict the most compromised fetuses in terms of growth retardation and requirements for neonatal intensive care.

Production and characterization of anti-RAS p21 monoclonal antibodies

Monoclonal antibodies (MAb) Ras 10 and Ras 11 were raised to an activated human Harvey-ras p21 and shown to react with recombinant p21 as well as p21 derived from human and rodent cells. Characterization studies by ELISA, immunoprecipitation and Western blot procedures demonstrated that MAb Ras 10 (IgG2a) and Ras 11 (IgG2b) react with normal p21, activated p21, and p21 from each of the Harvey, Kirsten and N-ras families. Studies illustrated that MAb Ras 10 and Ras 11 can also be used in flow cytometry and immunohistochemistry to specifically detect cellular p21. ELISA, immunoprecipitation and Western blot studies comparing rat anti-p21 MAb Y13-259 with Ras 10 and Ras 11 demonstrated that Ras 10 and Ras 11 had a greater sensitivity for ras protein detection than Y13-259. Collectively, these studies illustrate that MAb Ras 10 and Ras 11 can be applied to a variety of assay formats to detect ras proteins and, therefore, may be valuable tools in detecting and measuring of ras protein expression in normal, neoplastic and pre-neoplastic cells.

Differential recall as a source of bias in epidemiologic research

Differential recall between compared groups is discussed most often in the context of case-control studies. Cases, compared to controls, are suspected of providing a more complete report of their true exposure to an hypothesized risk factor, thereby biasing upwards the estimate of its effect. The present paper describes how differential recall can arise with any observational design in epidemiology; with any class of study variable, not only exposures; and may inflate or deflate the true value of the estimate of effect size. We list a variety of study designs and questionnaire tactics that aim to remedy these problems. The scope and magnitude of the bias created by differential recall and the efficacy of proposed remedies require further study.

Obesity and breast disease. The role of the female sex hormones

An Australian study of 513 women evaluated associations between obesity and both benign and malignant breast disease, and in particular investigated the role of female sex hormones. Women who gained more than 10 kg from early womanhood had a two-fold increase in risk of developing breast cancer, whereas lean women had a greater risk of being treated for benign breast disease. Obese women with breast cancer were more likely to have Stage II tumors but there was no significant association between obesity and tumor size or estrogen and progesterone receptor status. Obesity was strongly associated with the proportions of nonprotein-bound and albumin-bound estradiol, and inversely associated with sex hormone binding globulin (SHBG) levels and the proportion of SHBG-bound estradiol. In addition, age at menarche was inversely associated, and age at menopause directly associated with recalled weight at those time periods. These data demonstrate weight gain as a risk factor for breast cancer, and suggest a possible mechanism supporting its development.

Genetic analysis of eight loci tightly linked to neurofibromatosis 1

The genetic locus for neurofibromatosis 1 (NF1) has recently been mapped to the pericentromeric region of chromosome 17. We have genotyped eight previously identified RFLP probes on 50 NF1 families to determine the placement of the NF1 locus relative to the RFLP loci. Thirty-eight recombination events in the pericentromeric region were identified, eight involving crossovers between NF1 and loci on either chromosomal arm. Multipoint linkage analysis resulted in the unique placement of six loci at odds greater than 100:1 in the order of pter-A10-41-EW301-NF1-EW207-CRI-L581-CRI-L946 -qter. Owing to insufficient crossovers, three loci--D17Z1, EW206, and EW203--could not be uniquely localized. In this region female recombination rates were significantly higher than those of males. These data were part of a joint study aimed at the localization of both NF1 and tightly linked pericentromeric markers for chromosome 17.

Linkage studies with chromosome 17 DNA markers in 45 neurofibromatosis 1 families

A locus for von Recklinghausen neurofibromatosis (NF1) has recently been mapped near the chromosome 17 centromere. We have extended these linkage studies by genotyping 45 NF1 families with three DNA probes known to be linked to the chromosome 17 centromeric region. Of 34 families informative for NF1 and at least one of the three probes, 28 families show no recombinants with the disease gene. These data provide additional support for genetic homogeneity of NF1 and for a primary NF1 locus linked to the chromosome 17 centromere. Among the informative families were 7 families with apparent new NF1 mutations. Our data suggest that these mutations are probably at the chromosome 17 NF1 locus.

Hercon technology for transdermal delivery of drugs

The Hercon controlled drug delivery technology is based on a multi-layered laminated polymeric structure, in which a layer of vinyl chloride copolymer or terpolymer containing the drug is sandwiched between two or more layers of polymeric films. The drug is released from the device at a controlled rate by a process of diffusion through the reservoir and one of the outer layers, which can function as a rate controlling membrane. This basic technology has been successfully utilized for the development and commercialization of Nitroglycerin Transdermal System (NTS, Bolar Pharmaceutical Co., Inc). In vitro and in vivo investigations of transdermal delivery of different other drugs from the Hercon polymeric devices have indicated the feasibility of using this system to meet a variety of therapeutic needs.

Neurological soft signs. Their relationship to psychiatric disorder and intelligence in childhood and adolescence

Sixty-three male and 27 female adolescents known to have had neurological soft signs at the age of 7 years were compared with controls with no soft signs at age 7. Adolescents with early soft signs had significantly lower IQs and were more likely to have a psychiatric disorder characterized by anxiety, withdrawal, and depression. All the girls and 80% (12/15) of the boys with an anxiety-withdrawal diagnosis showed early soft signs. There was no relationship between early soft signs and attention deficit or conduct disorders. Examination of the relative contributions of anxiety at age 7, IQ, and social and family disadvantage to later diagnosis showed that most of the variance was accounted for by soft signs independently of IQ. Soft signs and anxious dependent behavior at age 7 were strongly predictive of persistent psychiatric disorder characterized by anxiety and withdrawal.

Prolonged outbreak of Norwalk gastroenteritis in an isolated guest house

During November and December 1982, a persistent outbreak of gastroenteritis took place in an isolated guest house. An estimated 26% of the changing population of guests and staff developed symptoms. Laboratory studies implicated Norwalk agent as the cause of illness, although the original source of the outbreak could not be established. Information on clinical features of the illness, its mode of spread, and eventual control is presented.

A pre-set ultraviolet dose meter

The design, construction and performance of an ultraviolet radiation (UVR) pre-set dose meter is described. The meter simultaneously displays irradiance, dose, and elapsed time, and incorporates a calibrated variable gain control to permit use with detectors of varying sensitivity. The meter has been developed to permit the automatic administration of UVR dose in photosensitivity testing. The UVR is generated by a Xenon lamp and delivered to the patient via a monochromator and liquid filled light guide. A beam-splitter in the light guide applicator diverts a small fraction (9%) of the UVR onto a photo-diode detector connected to the meter. When the dose recorded by the meter reaches the pre-set value the meter activates a solenoid which closes the monochromator exit slit shutter. This on-line control of the dose ensures that any fluctuations in irradiance are compensated so that the pre-set test dose is always administered to within the 1% accuracy of the instrument.

Hong Kong married abortion applicants: a comparison with married women who elect to complete their pregnancies

The authors compared 130 married abortion applicants with 100 married pregnant women who were attending the antenatal clinic. The abortion applicants were more likely to have had unhappy childhoods, broken homes, sexual pathology and more children. Their neuroticism scores on the Maudsley Personality Inventory were significantly higher. They tended to use either no contraception or unreliable methods. They were older and tended to report more socioeconomic problems. The characteristics of abortion applicants in this study seem to be similar to those reported from other countries.

Blood pressure in the first 6 weeks of life

Systolic blood pressure was measured at frequent intervals during the first 6 weeks of life in 99 normal neonates. Blood pressure rose from a mean of 70 mmHg at age 2 days, to 93 mmHg at age 6 weeks in babies awake; the majority of this rise (14 mmHg) took place in the first 2 weeks of life. The blood pressure measured when infants were asleep was lower than in those awake, but increased in a similar manner. Blood pressure of infants at 2 days was not significantly affected by method of delivery, or by the anaesthesia or analgesia that the mothers received in labour. It was not related to the Apgar score at one or five minutes.

The irreversible binding of benzo[a]pyrene to rat liver macromolecules in vivo and in vitro: effects of agents that influence benzo[a]pyrene metabolism

The present study was carried out to determine the effects of agents that influence benzo[a]pyrene (BP) metabolism in vitro on the irreversible binding of BP to rat hepatic macromolecules in vivo. The irreversible binding of [3H]BP was found to be both dose and time dependent after its intraperitoneal administration to male Wistar rats. The SKF 525-A, at doses of 50 and 75 mg/kg, ip 3 h before BP, decreased the level of binding from control by 31 and 34%, respectively. At 35 mg/kg, SKF-525-A had no effect. Diethyl maleate (0.6 mL/kg, ip) and cysteine (150 mg/kg, ip), 30 and 5 min before BP, respectively, did not alter the binding of BP from control. Oral methadone treatment, previously shown to increase selectively epoxide hydrase activity in male Wistar rats, also failed to alter the amount of BP bound to hepatic macromolecules. 3-Methylcholanthrene (20 mg/kg per day, ip, for 2 days) administered 24 h before BP, decreased the level of binding from control by 30%. Parallel in vitro studies were carried out with the various agents used in vivo.

Effect of specific trifluoroacetylation of individual cytochrome c lysines on the reaction with cytochrome oxidase

We have prepared three different cytochrome c derivatives, each containing a single specifically trifluoroacetylated lysine at residues 13, 55, and 99, respectively. The only modification that affected cytochrome c oxidase (EC 1.9.3.1) activity was that of lysine-13 at the top of the heme crevice. Trifluoroacetylation of lysine-13 increased the apparent Michaelis constant fivefold compared to that of native cytochrome c, but did not affect the maximum velocity. Trifluoroacetylation of lysine-55 at the left side of the cytochrome c molecule did not affect cytochrome oxidase activity in any way, nor did trifluoroacetylation of lysine-99 at the rear of the cytochrome c molecule. This indicates that the cytochrome oxidase binding site on cytochrome c involved only the front of the cytochrome c molecule and those lysines immediately surrounding the heme crevice.

Atomic absorption spectrophotometric determination of selenium in animal feed premix, using the vapor generation technique

An atomic absorption spectrophotometric method, using the vapor generation technique for the determination of selenium in animal feed premixes containing 0.4-0.002% selenium, is described. After the sample was digested in perchloric acid and hydrogen peroxide and reduced with 6M HCl, 3 aliquots of sample, each containing about 0.4 mug Se, were taken for analysis by the standard addition method. Sodium borohydride pellets were used for the generation of selenium hydride. The relative standard deviation of a single determination averaged +/- 19%.

Effect of chromosomal proteins extractable with low concentrations of NaCl on chromatin structure of resting and proliferating cells

When quiescent WI-38 cells are stimulated to proliferate by nutritional changes, the chromatin of stimulated cells shows an increased ellipticity in circular dichroism spectra and an increased ability to bind ethidium bromide. The differences between the chromatins of quiescent and stimulated cells are abolished if both chromatins are treated with 0.25 M NaCl. However, when salt-treated chromatins are reconstituted by dialysis agains 10 mM Tris-HCl, the difference in circular dichroism spectra and ethidium bromide binding re-appear. Furthermore, addition of the 0.25 M NaCl extract from chromatin of stimulated cells to chromatin of quiescent cells causes an increased ellipticity in circular dichroism spectra similar to that of stimulated chromatin. Since only proteins (mostly nonhistones) are detectable in the 0.25 M NaCl extract, these results strongly suggest that the chromosomal proteins extractable with low concentrations of salt are responsible for the functional and structural changes occurring in chromatin of WI-38 cells stimulated to proliferate.

The chemical shifts of the methoxyl in anisole derivatives

The n.m.r. spectra of anisole and 20 methyl-, t-butyl-, adamant-1-yl-, and chloro-substituted anisoles were obtained in dilute solutions in CCl4, CHCl3, and C6H6. In the non-aromatic solvents the methoxyl proton resonance shifts upfield with di-o-alkyl substitution, relative to anisole or o-alkyl substitution. However, this upfield shift is not observed in the case of di-o-chloro substitution. In benzene the methoxyl resonance exhibits the aromatic-solvent induced shift, and this shift is larger with ortho than with di-ortho substitution. Relative to anisole, alkyl substitution at the para or meta position shifts the methoxyl resonance slightly upfieid in the non-aromatic solvents, but slightly downfield in benzene. However, chloro substitution at the ortho or the para position shifts this resonance upfield in benzene. In the mono-o-substituted derivatives, the methoxyl resonance shows a doublet structure, consistent with spin-spin coupling with the o-proton (J c. 0.20 Hz).