Histone-DNA contacts in the 167 bp 2-turn core particle

The histone-DNA contacts in the 167 bp 2-turn core particle have been compared with those in the 146 bp 1.75-turn core particle by the methodology developed by Mirzabekov and his colleagues. The contacts in the 167 bp 2-turn core particle retain the essential features of those in the 146 bp 1.75-turn core particle but contacts for histones H3 and H2A were found in the 10 bp extension that discriminates the two particles. In addition the contact for histone H2A near the dyad axis was far more pronounced in the case of the 146 bp core particle.

ERICA predicts response to tamoxifen in elderly women with breast cancer

Oestrogen receptor status has been determined by an immunocytochemical assay using fine-needle aspiration samples of primary breast cancers in elderly patients. In a prospective study 56 patients were treated with tamoxifen only. Satisfactory assays were achieved in 49 patients. Disease was controlled by tamoxifen in 32 of 35 (91%) patients with oestrogen receptor positive tumours, compared with only 1 (7%) of 14 who were receptor negative. Immunocytochemical assay on fine-needle aspiration samples is relatively non-invasive and simple to perform, it accurately predicts response to tamoxifen in elderly patients and can be used to select patients for tamoxifen only therapy.

Primary vesicoureteric reflux: treatment with subureteric injection of Polytef paste

A series of 34 children with 40 primary refluxing ureters were treated endoscopically with a subureteric injection of polytetrafluoroethylene paste (Polytef). The amount injected ranged between 0.1 and 0.8 ml (mean 0.3). A single injection cured the reflux in 26 ureters (65%) and the grade of reflux improved in a further 9 ureters. Seven ureters required a second injection and reflux was cured in 6 of these. The overall cure rate was therefore 80% after the second injection. There was one complication due to self-limiting ureteric obstruction following injection. The procedure is quick, easy to perform and effective. We have some reservations about the long-term efficiency and safety of subureteric Polytef injection in children.

Extended C-terminal tail of wheat histone H2A interacts with DNA of the "linker" region

The preparation of hybrid histone octamers with wheat histone H2A variants replacing chicken H2A in the chicken octamer is described. The fidelity of the reconstituted hybrid octamers was confirmed by dimethyl suberimidate cross-linking. Polyglutamic-acid-mediated assembly of these octamers on long DNA and subsequent micrococcal nuclease (MNase) digestion demonstrated that, whereas chicken octamers protected 167 base-pairs (representing 2 full turns of DNA), hybrid histone octamers containing wheat histone H2A(1) with its 19 amino acid residue C-terminal extension protected an additional 16 base pairs of DNA against nuclease digestion. The protection observed by hybrid histone octamers containing wheat histone H2A(3) with both a 15 residue N-terminal and a 19 residue C-terminal extension was identical with that observed with H2A(1)-containing hybrid histone octamers with only the 19 residue C-terminal extension. These results suggest that the role of the C-terminal extension is to bind to DNA of the "linker" region. The thermal denaturation of chicken and hybrid core particles was identical in 10 mM-Tris.HCl.20 mM-NaCl, 0.1 mM-EDTA, confirming that there was no interaction between the basic C-terminal extension and DNA of the core particle. Denaturation in EDTA, however, showed that hybrid core particles had enhanced stability, suggesting that the known conformational change of core particles at very low ionic strength allows the C-terminal extension to bind to core particle DNA under these conditions. A model accounting for the observed MNase protection is presented.

Intra-uterine starvation and fetal leucocyte count

In 104 severely growth-retarded fetuses, the mean white blood cell count (WBC), as well as neutrophil, lymphocyte and monocyte counts were reduced. Furthermore, the severity of the leucopenia was significantly related to the degree of fetal 'smallness' and anaemia. These findings suggest that leucopenia observed in growth-retarded neonates may be a consequence of intra-uterine starvation due to deficiency of haematinics.

Irreducible inguinal hernia in children below two years of age

Eighty-five cases of irreducible inguinal hernia in children below 2 years of age were reviewed. Non-operative treatment was successful in 71 (84 per cent); 14 children required emergency surgery. The younger the child and the longer the duration of symptoms at presentation, the worse was the outcome of non-operative treatment. In 35 (41 per cent) children the diagnosis of inguinal hernia had been made before irreducibility. There is an increased incidence of postoperative complication associated with irreducibility, especially in preterm infants. Early diagnosis of inguinal hernia in young children and prompt referral for surgery is recommended.

Metabolism of normal skeletal muscle during dynamic exercise to clinical fatigue: in vivo assessment by nuclear magnetic resonance spectroscopy

In vivo nuclear magnetic resonance (NMR) spectroscopy was used to define several intracellular high energy phosphate variables of the gastrocnemius muscle of normal subjects during rest, graded plantar flexion exercise to exhaustion, and recovery. There were nine males and eight females with an average age of 34 +/- 8 years. At rest, pH averaged 7.09 +/- 0.03 and the energy cost index (ECI)--the ratio of inorganic phosphate to phosphocreatine--averaged 0.13 +/- 0.03. At peak exercise, the ECI increased markedly to 2.71 +/- 2.0 (P less than 0.001) and pH fell precipitately to 6.76 +/- 0.17 (P less than 0.001), indicating the high intensity of the exercise. Exercise endurance averaged 12 +/- 5 mins; it was not highly correlated with sex, age (r = 0.35), rest pH (r = 0.26), rest ECI (r = 0.38), peak exercise pH (r = 0.23) or peak exercise ECI (r = 0.38), nor exercise changes in pH (r = 0.17) and ECI (r = 0.28). At 23 mins post exercise all variables were similar to rest. Rest pH was the only variable different between males (7.10 +/- 0.03) and females (7.07 +/- 0.03) (P less than 0.05). Thus, dynamic exercise of large skeletal muscles in normal subjects was characterized by marked temporal changes in high energy phosphate profiles and very low pH at exhaustion. No single metabolic variable correlated highly with exercise endurance, suggesting that the intracellular pathophysiology of exhaustive muscle exercise and clinical fatigue may be multifactorial.

Acute myocardial infarction: contemporary risk and management in older versus younger patients

The in-hospital management and risk of death of 101 patients 70 years of age or older with acute myocardial infarction in 1987 (group 1) were compared with management and risk for 106 temporally matched patients less than 70 years old (group 2). In group 1, 49% had histories of previous myocardial infarction, compared to 25% in group 2 (P less than 0.001), and 23% of group 1 presented without cardiac pain, versus 7% of group 2 (P less than 0.001). Among the younger patients, other conventional risk factors were, in contrast, more common (Q wave infarction 84% in group 2 versus 70% in group 1; P less than 0.05) or higher (peak creatine kinase values 2222 iu/L in group 2 versus 1366 iu/L in group 1; P less than 0.001). Prior to infarction, all cardiac drugs were used more frequently in the older group 1 patients, whereas post infarction thrombolysis, beta-blockers and acetylsalicylic acid use were all more common (P less than 0.01 to P less than 0.001) in the younger group 2 patients. Post infarction exercise testing, left ventricular ejection fraction calculations and coronary angiography were all performed less frequently in group 1 (P less than 0.001). The in-hospital mortality was 35% for group 1 versus 7% for group 2 (P less than 0.001). Among all 207 study subjects, multiple logistic regression revealed thrombolysis, absence of cardiac pain, and age 70 years or older to be associated with the greatest relative mortality risk. Increased relative risk to a lesser degree was associated with previous infarction, male sex and post infarction use of antiarrhythmic medication.(ABSTRACT TRUNCATED AT 250 WORDS)

The reliability of diagnostic coding in psychiatric case registers

In total, 103 cases were randomly selected from the Groningen, Nottingham and South Verona registers. Six raters (two in each of the register areas) were involved in coding these cases according to the ICD-9. In general, interrater agreement was satisfactory when codes were grouped into a limited number of categories. Nevertheless, considerable variation in agreement rates was found. We distinguished three steps in the diagnostic process. The selected logistic model showed that reliability is significantly affected in each step, but only substantial in the first where clinicians formulate a diagnosis.

An analysis of 300 EEG referrals

Although the EEG suffers from limited diagnostic significance it is a useful adjuvant to diagnosis and demands for the examination are increasing. Three hundred consecutive referrals to one unit are analysed.

Distribution and metabolism of 1,2,4-trimethylbenzene (pseudocumene) in the rat

1. Single doses of 1,2,4-trimethylbenzene (124TMB) or 14C-124TMB were administered orally to rats for metabolism and distribution studies. 2. 14C-124TMB was rapidly and widely distributed throughout the body with the highest levels in adipose tissue. No other preferential uptake of 14C-124TMB by any of the organs or tissues examined was evident. 3. Tissue levels declined rapidly within 24 h after dosage, with more than 99% of the administered radioactivity recovered in the urine during this period. 4. A complex mixture of isomeric trimethylphenols, dimethylbenzyl alcohols, dimethylbenzoic acids and dimethylhippuric acids excreted in the urine accounted for more than 81% of the administered dose. The major metabolites were 3,4-dimethylhippuric acid (30.2% dose), 2,4-dimethylbenzyl alcohol (12.7% dose, primarily as sulphate and glucuronide conjugates) and 2,5-dimethylbenzyl alcohol (11.7% dose, primarily as sulphate and glucuronide conjugates).

The effect of sublingual nifedipine on uteroplacental blood flow in hypertensive pregnancy

The effect of nifedipine on uteroplacental blood flow was investigated in nine hypertensive women in the trimester of pregnancy and compared with the effects of a placebo in nine similar hypertensive women. An index of uteroplacental blood flow was obtained, twice before treatment and once after treatment, by measuring the increase in radioactivity in the region of the placenta with a gamma camera following an intravenous injection of indium-113m. There was no significant change in the blood flow index in either the nifedipine- or the placebo-treated groups despite a significant fall in blood pressure with nifedipine. Nifedipine lowers the blood pressure without any apparent reduction in uteroplacental blood flow.

Discussion of the optics of a new 3-D imaging system

The geometric optics of a new 3-D imaging system, which has several innovative features, is discussed. The principles governing the primary design of the system are considered in some detail, and the calculation method employed in achieving the basic design parameters is presented. The aberration of the system is then investigated in detail using primary aberration theory, and the limitations imposed on a light beam passing through the arrangement is discussed quantitatively.

Three-dimensional imaging systems: a new development

An optical system which produces 3-D images exhibiting continuous parallax with no flipping or cardboarding is described. Both integral and lenticular images can be recorded on photographic film without recourse to a specialized environment. Standard photographic processing and enlarging techniques are used to obtain hard copy. Measurements on commercially available retrodirective screens and a new retroscreen arrangement show that the new screen developed gives significant advantages. A retrodirective and a transmission version of the system have been constructed.

A comparison of gemeprost (Cervagem) pessaries and Lamicel tents for cervical preparation for abortion by dilatation and suction

In a randomized, single-blind trial, 78 women having vaginal termination of pregnancy were treated with either a 1-mg gemeprost (Cervagem) pessary or a Lamicel tent inserted 3-4 h before operation. Both agents produced satisfactory cervical softening but dilatation was significantly easier after gemeprost. Pre-operative side-effects were more frequent after gemeprost but did not increase the need for analgesia. There were no differences between the two groups with regard to either postoperative symptoms and analgesic requirements or pre-operative and postoperative temperature, pulse rate and blood pressure. Gemeprost pessaries are easier, faster and less uncomfortable to administer.

Isolation, biochemical characterization, and culture of lung type II cells of the rat

A method is described for the isolation of rat lung epithelial Type II cells using trypsin digestion of tissue to release cells for subsequent separation by Percoll gradient centrifugation. Both the concentration of trypsin and the age (body weight) of the rat affect the yield from primary digestion and the final number of Type II cells obtained. A lung weighing 1 g from a 200 g rat yields approximately 30 X 10(6) washed Type II cells (approximately 25% of the total estimated lung population). These cells have a plating efficiency of 40-50% after 48 h of culture. The cells have a high alkaline to acid phosphatase ratio (usually greater than 4.0) compared with that of alveolar macrophages (0.1) and accumulate putrescine by an active transport mechanism with an apparent KM between 8 and 14 microM. Together with studies of [3H]thymidine uptake into DNA, which is maximal between 48 and 72 h of culture, these quantitative measurements form a good basis for investigating the interactions between a number of chemical agents and Type II cells in vitro.

Carcinoma associated with augmentation cystoplasty

Three patients with augmentation ileocystoplasties developed carcinoma at the ileovesical junction 7, 22 and 24 years after surgery. All were originally reconstructed for genitourinary tuberculosis and all had developed huge capacity ileal segments with large residual urines, associated with recurrent urinary tract infection. With the current trend for using small bowel for both augmentation and substitution cystoplasty, balanced voiding must be achieved and maintained, and long-term follow-up is mandatory.

Venereal trichomoniasis: role of men

It has been suggested that high zinc concentrations found in men may prevent Trichomonas vaginalis from being established in the male reproductive tract. In this investigation T vaginalis was readily killed at concentrations of zinc that occur in the prostatic fluid of healthy men (minimum trichomonacidal concentration (MTC) of 6.4 mmol/l). T vaginalis was also shown to be killed by human prostatic extracts as well as by human seminal fluid, even when the zinc content was much lower than the MTC for T vaginalis. It seems likely, therefore, that there are at least two antitrichomonal mechanisms in the male reproductive tract, one being zinc dependent and the other not relating to zinc content. Tritrichomonas foetus, which causes venereal trichomoniasis in cattle, was unaffected by bovine seminal fluid and was killed by zinc only at concentrations far higher than those found in the prostatic fluid in the bull (MTC 200 mmol/l).

The complications of colposuspension

Fifty patients with stress incontinence treated by a colposuspension procedure were reviewed symptomatically and urodynamically before and after surgery and followed up for 1 to 6 years (mean 4.5). Although 84% were continent post-operatively, only 63% of those previously operated on for incontinence were dry, and only 44% were dry and complication-free in the long term.