Progressive abrogation of TGF-beta 1 and EGF growth control is associated with tumour progression in ras-transfected human keratinocytes

This study examined the response of human keratinocytes in different stages of transformation to exogenous TGF-beta 1 and EGF as well as their receptor and growth-factor expression. Cells of the spontaneously immortalized HaCaT cell line and c-Ha-ras transfected clones (I-6, I-7, II-3, II-4) exhibited different tumorigenic potentials when transplanted to athymic mice. HaCaT- and I-6 cells were non-tumorigenic, I-7 cells formed persisting epidermal cysts (benign tumours) and II-3 and II-4 cells developed into invasive squamous-cell carcinomas. TGF-beta 1 inhibited thymidine uptake in a dose-dependent manner, a progressive decrease in response being associated with an increasing malignant potential (HaCaT greater than I-6 greater than I-7 = II-4). HaCaT-cells and ras-clones expressed TGF-beta 1 mRNA at similar levels, but cells of increasing malignant potential secreted markedly less receptor-binding TGF-beta (HaCaT greater than I-6 = I-7 greater than II-3 greater than II-4) into the culture medium. Whilst ras-transfected cells expressed fewer TGF-beta receptors than HaCaT cells, there was little difference between TGF-beta receptor number or affinity between the 4 transfected cell clones. The same was true for the TGF-beta receptor types, but Type-II receptors were expressed at lower levels by the malignant clones II-3 and II-4. When HaCaT and ras-transfected cells were investigated for their response to exogenous EGF, cells were refractory (I-7, II-4), partially stimulated (I-6) or fully stimulated (HaCaT). Cells with increasing malignant potential produced increasing amounts of endogenous TGF-alpha (II-4 = II-3 greater than I-7 = I-6 greater than HaCaT). All tumorigenic ras clones expressed higher mRNA levels than HaCaT-cells. Ras-transfected clones expressed fewer high- and low-affinity EGF receptors than HaCaT cells with a tendency toward increased numbers of high-affinity EGF receptors associated with increasing malignant potential (II-4 = II-3 greater than I-7 greater than I-6) but these changes were associated with a progressive decrease in receptor affinity. The results indicate that tumour progression in human epidermal keratinocytes transfected with c-Ha-ras is associated with a progressive abrogation of TGF-beta 1 and EGF growth control. They suggest that the increased autonomous growth potential associated with advanced stages of epithelial tumour progression can be defined more closely using a cellular profile of TGF-beta and EGF.

Retinal blood flow in diabetic retinopathy

OBJECTIVES

(a) To report on the basic parameters of retinal blood flow in a population of diabetic patients with and without retinopathy and non-diabetic controls; (b) to formulate a haemodynamic model for the pathogenesis of diabetic retinopathy from this and other studies.

DESIGN

Laser-Doppler velocimetry and computerised image analysis to determine retinal blood flow in a large cross sectional study.

SETTING

Diabetic retinopathy outpatient clinic.

SUBJECTS

24 non-diabetic controls and 76 diabetic subjects were studied (63 patients with insulin dependent diabetes, 13 with non-insulin dependent diabetes). Of the diabetic subjects, 12 had no diabetic retinopathy, 27 had background retinopathy, 13 had pre-proliferative retinopathy, 12 had proliferative retinopathy, and 12 had had pan-retinal photocoagulation for proliferative retinopathy.

MAIN OUTCOME MEASURES

Retinal blood flow (microliters/min) and conductance (rate of flow per unit of perfusion pressure).

RESULTS

In comparison with non-diabetic controls (9.52 microliters/min) and diabetic patients with no diabetic retinopathy (9.12 microliters/min) retinal blood flow was significantly increased in all grades of untreated diabetic retinopathy (background 12.13 microliters/min, pre-proliferative 15.27 microliters/min, proliferative 13.88 microliters/min). There was a significant decrease in flow after pan-retinal photocoagulation in comparison with all the other groups studied (4.48 microliters/min). Conductance of the retinal circulation was higher in the untreated diabetic retinopathy groups. These results were independent of age, sex, type of diabetes, duration of diabetes, glycated haemoglobin concentration, blood glucose concentration, blood pressure, and intraocular pressure.

CONCLUSIONS

Retinal blood flow is significantly increased in diabetic retinopathy in comparison with non-diabetic controls and diabetic subjects with no retinopathy. This has implications for controlling hypertension and hyperglycaemia as a strategy in reducing morbidity from diabetic retinopathy.

Effect of mixture of surfactants and adsorbents on anaerobic digestion of water hyacinth-cattle dung

In an effort to improve the anaerobic digestion of water hyacinth-cattle dung with enriched methane content, the effects of mixtures of surfactant-surfactant, adsorbent-adsorbent and surfactant-adsorbent have been studied in various combinations. Among the combinations tested, bentonite and gelatin, gelatin and Tegoprens 43, sodium lauryl sulfate and Tegoprens 42, and Tegoprens 47 and Tegoprens 63 showed more than a 100% increase in gas production with higher methane yield.

Spinal oxygenation, blood supply localization, cooling, and function with aortic clamping

Similar to other methods of organ preservation, "spinoplegia" may protect the spinal cord from the effects of oxygen desaturation during aortic cross-clamping. In porcine experiments, spinal cord O2 saturation was studied during intraoperative localization of the blood supply to the spinal cord using hydrogen; division of arteries not supplying the spinal cord; aortic cross-clamping for 60 minutes; and 60 minutes after unclamping. In 5 animals, 120 mL of cold saline solution with lidocaine (100 mg/dL) was infused into the aorta during aortic cross-clamping. During sequential localization, O2 saturation dropped by 40.02% (standard deviation, 20.16%) for T-14 artery testing versus a decrease of 17.27% (standard deviation, 11.88%; p = 0.0075) for L-5 artery segment testing in the control animals and returned to baseline thereafter. During aortic cross-clamping maximal O2 desaturation was 5% of baseline (15.7%; p less than 0.0001), which improved slightly by 30 minutes after clamping (48% of baseline +/- 37.37%; p = 0.048 versus maximum) and then returned to baseline (97.1% of baseline +/- 41%) with unclamping; 5 minutes later, hyperoxygenation occurred with a progressive decline thereafter (68% of baseline +/- 29.3%; p = 0.025, 45 minutes after unclamping versus baseline). The decrease in spinal motor evoked potentials was significantly less (p less than 0.02) in the treated group. Intraoperative hydrogen testing in 8 patients was demonstrated to be safe. It accurately localized reattached arteries, and O2 saturation of the spinal cord fell by 56% (standard deviation, 29%; p = 0.0025) with aortic cross-clamping. We conclude that spinal cord ischemia occurs with aortic cross-clamping in both animals and humans.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagonal earlobe creases and atheromatous disease: a postmortem study

The association between the grade of earlobe creases and degree of atheromatous disease was investigated in 376 postmortem examinations. Each earlobe crease was individually graded from 0 to 3. The risk of atherosclerosis as a cause of death was nearly doubled in men with grade 3 creases in both earlobes, and more than trebled in women with bilateral high-grade creases. The risk of death from myocardial infarction was 2.50 in men with high-grade creases and 3.70 in women. The earlobe crease is an important sign of atheromatous disease and it may be useful to include it in the clinical examination of patients.

The effect of anticonvulsants on cognitive functioning following a probable encephalitic illness

A 54-year-old man developed an acute encephalitic illness and subsequently suffered from marked memory difficulties. Considerable improvement with anticonvulsant therapy was demonstrated using a ward-based observation programme and serial neuropsychological assessments. The case report highlights the prominent role played by epileptic activity in determining the severity of the patient's amnesia.

Incarceration of existing inguinal hernia as a complication of pulmonary function testing

Pulmonary function testing (PFT) has not been listed as a risk for development of incarceration in an existing inguinal hernia. We report two patients who developed this complication after routine preoperative PFT. We also present data of our retrospective review of eight patients with inguinal hernia who were referred for preoperative PFT. Two out of eight patients suffered incarceration of an existing inguinal hernia. We found no significant difference in mean age, weight, smoking habits, number of forced expiratory maneuvers, time of sustained forced expiratory maneuver, or any PFT data between the groups with and without incarceration. Thus, incarceration of inguinal hernia could not have been predicted prior to PFT and was not related to other factors such as obesity or more severe airway obstruction.

Aggressive behaviour in elderly psychiatric inpatients

We describe the types of aggressive behaviour and determine their prevalence in a sample of hospitalized elderly psychiatric patients. Data were obtained by nurse ratings of aggressive behaviour using the recently developed Rating Scale for Aggressive Behaviour in the Elderly; 90 patients were rated over a 3-d period. Nearly half the sample were at least mildly aggressive; the frequencies of some specific types of aggressive behaviour were high. In contrast, the frequency of injuries and the use of restraints and medication for aggressive behaviour were low. Some correlates of the aggressive behaviour were also analysed.

Non-completion of active orthodontic treatment

This paper reports a retrospective study of patient factors which might be associated with failure to complete orthodontic treatment in a hospital and in a specialist practice. Case records of patients commencing treatment were examined and targeted for further investigation by mailed questionnaires. There was a statistically significant difference in the discontinuation rate between the two groups of patients. Precise reasons for the differences could not be isolated, but did not appear to be related to the age of the patient at the start of treatment.

A rating scale for aggressive behaviour in the elderly--the RAGE

A 21-item rating scale for measuring aggressive behaviour in psychogeriatric in-patients is described. This scale is designed to be completed by ward staff. It should prove valuable in treatment studies and in studies which aim to investigate the correlates of aggressive behaviour. Studies using the scale demonstrate that when used in conjunction with a ward check list the scale has high reliability and validity.

Phosphorylation occurs in the amino terminus of the Raf-1 protein

The ability of the Raf-1 protein to morphologically transform murine fibroblasts can be activated by amino-terminal deletions or substitutions. We have compared the phosphorylation states of full-length and representative transforming and non-transforming amino-terminal deletion mutants of the Raf-1 protein using phosphoamino acid analysis and tryptic phosphopeptide mapping. Several [32P]orthophosphate-labeled tryptic phosphopeptides that were present in the full-length Raf-1 protein were absent from the highly transforming 22W Raf-1 mutant (lacking 305 amino-terminal residues). Peptide-specific antisera localized Raf-1 phosphorylation sites to several amino-terminal cyanogen bromide and tryptic peptides that are deleted from the 22W protein. A major phosphorylated tryptic peptide of the Raf-1 protein was immunoprecipitated by antiserum directed against amino acid residues 257-275, a highly conserved region of the raf family. This tryptic peptide is entirely deleted from the highly transforming 22W protein. Subtractive Edman degradation and electrophoretic analysis of the immunoprecipitated tryptic peptide indicated that phosphorylation of the Raf-1 protein occurs at serine 259. Multiple phosphorylated tryptic peptide forms were immunoprecipitated by antiserum directed against Raf-1 residues 283-309. The majority of this tryptic peptide is also deleted from the highly transforming Raf-1 mutant 22W.

Disopyramide analysis using REMEDi: comparison with EMIT and conventional high performance liquid chromatographic methods

REMEDi (Rapid EMErgency Drug identification; Bio-Rad) is an automated high performance liquid chromatographic (HPLC) system designed to detect, identify and measure a range of basic and neutral drugs in 0.5-1.0 mL of urine or plasma/serum. We have evaluated REMEDi in the analysis of the antiarrhythmic drug disopyramide in patient samples. The specimens were also analysed by a conventional HPLC method, based on solvent extraction and UV detection (254 nm), and by EMIT. There were good correlations between the results obtained with each method (r = 0.91 or greater). REMEDi gave a lower mean result than EMIT [means +/- SD (mg/L): REMEDi 2.64 +/- 1.10, EMIT 3.14 +/- 1.51; t = 4.0, p less than 0.01; n = 25], but there were no other significant differences in mean results. The principal disopyramide metabolite, mono-N-desalkyldisopyramide, did not interfere in any method. Clearly REMEDi can be used for therapeutic drug monitoring of disopyramide provided enough sample is available.

Multicenter randomized clinical trial of home uterine activity monitoring for detection of preterm labor

Home uterine activity monitoring has been described as an effective means of detecting uterine contractions, but controversy exists whether it is home uterine activity monitoring or increased nursing support in conjunction with it that contributes to earlier detection of preterm labor. In this study 377 women at risk for preterm labor from three centers were prospectively, randomly assigned to high-risk prenatal care alone (not monitored) or to the same care with twice-daily home uterine activity monitoring without increased nursing support (monitored). The two groups were medically and demographically similar at entry into the study. Routine visits, nonroutine visits, and gestational age at diagnosis of preterm labor were similar in both groups. Preterm labor occurred in 41 of 198 monitored and 39 of 179 not monitored patients. Mean cervical dilatation was 1.4 cm in 41 monitored compared with 2.5 cm for 37 not monitored (p = 0.0006); 73.1% of monitored and 27.5% of not monitored had preterm labor detected before 2 cm dilatation (p = 0.00009). Neonatal outcome of singleton pregnancies showed greater birth weight, fewer days in the neonatal intensive care unit, and fewer babies requiring oxygen therapy and mechanical ventilation in the monitored group. The better outcomes are probably due to the increased likelihood of diagnosis of preterm labor before advanced cervical dilatation with home uterine activity monitoring, thus providing the clinician with a better chance to initiate tocolytic therapy directed at improving pregnancy outcome.

Influence of preservation or perfusion of intraoperatively identified spinal cord blood supply on spinal motor evoked potentials and paraplegia after aortic surgery

Permanent ligation of arteries supplying blood to the spinal cord in operations for aortic aneurysm can lead to spinal cord ischemia, which can result in either paraparesis or paraplegia. This report describes a rapid method of intraoperative identification of those arteries that supply the spinal cord by use of an intrathecal platinum electrode to detect hydrogen in solution that has been injected into the aortic ostia. Preservation or perfusion of those identified arteries supplying the spinal cord may decrease the rate of postoperative neurologic complications. Of 28 porcine experiments with postoperative observation for 24 hours, there were 3 initial pilot experiments in which saline saturated with hydrogen was injected into the temporarily cross-clamped aorta. Twenty animals were then randomized to (1) preservation of only the vessels sequentially identified to supply blood to the spinal cord from T-13 to L-5 (n = 10); (2) division of the vessels supplying the spinal cord (n = 10). A further five animals underwent perfusion experiments wherein the identified cord arteries were perfused by a shunt, the other nonsupply arteries were divided, and the aorta was kept clamped for 45 minutes. Spinal motor evoked potentials were elicited with an intrathecal electrode and were highly sensitive for paralysis. Paralysis occurred in 0/3 pilot (p less than 0.013 vs division); 8/10 division; 1/10 preservation (p less than 0.0017 vs division); and perfusion 1/5 (p less than 0.025 vs division). Results of a pilot study in eight humans shows that the technique can be used to rapidly identify segmental arteries supplying the spinal cord, to determine if distal perfusion is supplying the spinal cord with blood flow, and if reattached segmental arteries are patent.

Studies on the immunogenicity of Chinese hamster ovary cell-derived recombinant gp120 (HIV-1IIIB)

Recombinant DNA-derived gp120 (HIV-1IIIB) expressed in chinese hamster ovary cells elicited specific humoral and cell-mediated immune responses in a variety of mammals. Antisera from immunized rabbits, sheep and goats recognized virus-derived gp120 and its precursor (gp160). Neutralizing antibodies were also elicited, but only in a few animals, and this may be related to the protein's susceptibility to cleavage through the neutralizing domain. However, in rabbits the degree of cleavage of gp120 had little or no effect on its antigenicity or immunogenicity. All antisera had limited cross-reactivity to envelope glycoproteins from a panel of HIV-1 isolates suggesting that immunodominant antibody epitopes are in variable regions of the recombinant gp120. Antigen-specific T-cell responses were detected in immunized macaques and were found to be stronger and more prolonged when gp120 was administered in Freund's adjuvant rather than alum.

Darkroom transplant

Manual film processing systems produce their own types of artefacts. The authors report accidental transfer of an image-bearing emulsion from one film to another. The films were lying in close apposition in the darkroom washing tank. Forcible separation of the two films resulted in the "transplant".

Preliminary report of localization of spinal cord blood supply by hydrogen during aortic operations

One source of paraplegia after aortic operations is the failure to reattach the spinal cord blood supply, the origins of which are not evident at operation. This report is concerned with a rapid new method of identifying these vessels intraoperatively. In 9 pigs, a specially designed catheter with platinum and stainless steel electrodes was inserted intrathecally. Saline solution saturated with hydrogen was injected sequentially into arterial ostia at T-15 to L-4 inclusive, and the generated current impulses from the conditioned platinum electrode were recorded. Of 90 potential segmental arteries supplying the spinal cord, 28 gave rise to spinal radicular arteries. Hydrogen-induced current impulses correctly located 25 of the radicular arteries and all those larger than 180 microns in diameter. When injected with indigo carmine, the vessels localized by the hydrogen-induced current impulses filled the entire anterior spinal artery from the low thoracic to the sacral region, whereas injection of the other vessels did not show filling. After refinement and testing for safety, this method has been employed clinically to rapidly localize and reattach routes of critical cord circulation.

Development of aneuploidy in experimental oral carcinogenesis

Using the rat model of oral carcinogenesis in which cell lines were derived from tissue after in vivo and in vitro treatment with the carcinogen 4-nitroquinoline-N-oxide (4NQO), we have shown that aneuploidy is generally associated with the ability of cells to form colonies in an anchorage-independent environment and to form tumours in athymic mice. In one cell line derived from 4NQO treatment in vitro, there was evidence that aneuploidy was an early marker, preceding anchorage independence and tumorigenicity in athymic mice. However, this was an inconsistent finding in other cell lines and the use of aneuploidy as an early marker of pre-malignancy should be treated with caution.

Presynaptic calcium currents recorded from calyciform nerve terminals in the lizard ciliary ganglion

Electron microscopic examination of ciliary ganglion from Anolis carolinensis shows large calyciform presynaptic nerve terminals ending on ganglion cells. Intracellular records were obtained from the terminals, and membrane currents were recorded with the single-electrode voltage clamp technique. After block of Na+ currents with tetrodotoxin, depolarization of the terminals produced inward currents that disappeared when extracellular Ca2+ was removed, and increased in magnitude and duration when competing outward currents were blocked by intracellular Cs+. Thus it is possible, with this preparation, to record and characterize Ca2+ currents presumably associated with neurotransmitter release.

The production and characterisation of monoclonal antibodies against human prolactin and the development of a two-site immunoradiometric assay

Monoclonal antibodies against human prolactin (PRL) have been produced and characterised and used to develop a sensitive two-site immunoradiometric assay (IRMA). Nine anti-PRL monoclonal antibodies were assessed for reactivity in immunoblotting experiments with PRL, hPL, hGH and pituitary gland extract. There was no detectable crossreactivity with hPL or hGH. In liquid phase radioimmunoassay (RIA) studies using three of the antibodies there was no detectable crossreaction from hPL or hGH. Five antibodies were positive in immunocytochemical studies using sections of human pituitary gland. Using FPLC purified monoclonal antibodies, a two-site IRMA was developed that could assay PRL over the range 17.5-3500 mIU per litre and was readily adapted to assaying serum samples from patients. The two-site IRMA could be performed within one day without loss of sensitivity and has potential as a rapid and simple method for screening clinical samples.