Screening for glaucoma: age and sex of referrals and confirmed cases in England and Wales

This paper is based on a prospective survey covering 275,600 sight tests by optometrists in England and Wales. It analyses the age and sex distribution of 1402 referrals for suspected glaucoma and 456 confirmed cases of the disease. The proportion of sight tests which led to a confirmed case increased with age, for both sexes, to a maximum at approximately 70 years, and then tended to decline. Cases of glaucoma in people aged 36-51 years accounted for about a tenth of the total, which is more than is generally recognized. Wider adoption of routine tonometry for middle aged people would help to ensure that these cases are detected at an early stage. Confirmed cases of glaucoma in which raised intraocular pressure had not been given as a reason for referral, i.e. probable low tension glaucomas, increased from 5% of patients < 51 years old to 13% of patients > 75 years old. Glaucoma was found to be much more common in men.     

Effect of timolol versus pilocarpine on visual field progression in patients with primary open-angle glaucoma.

BACKGROUND: Relatively few studies have been conducted linking decreasing intraocular pressure (IOP) to preservation of visual field. This investigation was conducted to determine if this link could be made and to compare the long-term effect of two ocular hypotensive agents on preservation of visual field. METHODS: In an observer-masked study, 189 patients with primary open-angle glaucoma received either timolol or pilocarpine by random allocation. The dose of antiglaucoma agent was increased from 0.25% to 0.5% twice daily for timolol or from 2% to 4% four times daily for pilocarpine if the initial IOP response was inadequate. After an on-treatment baseline, visual fields were followed every 4 months for 2 years using the Octopus program 32. RESULTS: Compared with timolol, significantly more patients receiving pilocarpine discontinued use because of inadequate IOP control (P < or = 0.01). By comparing the mean visual field scores, it can be seen that the pilocarpine group had a significantly worse score at all timepoints from month 4 to month 24. The pilocarpine group also had a greater mean number of test loci with decreased sensitivity of 5 or more decibels (dB) at all timepoints. The mean within-patient regression slope for timolol was 0.01 dB/month and for pilocarpine was -0.06 dB/month (P < 0.01). The study has shown that over a 2-year period, patients treated with pilocarpine 2% or 4% four times daily experienced a significantly greater visual field deterioration than that seen in patients receiving either 0.25% or 0.5% timolol twice daily. CONCLUSION: Although these data do not support a link between lowering of IOP and visual field preservation, treatment with timolol was associated with significantly less visual field loss than treatment with pilocarpine.     

Evidence for monoclonal T lymphocyte proliferation in angioimmunoblastic lymphadenopathy.

The arrangement of the T cell receptor and immunoglobulin genes was analysed in lymphoid tissue biopsy specimens from 25 cases of angioimmunoblastic lymphadenopathy. Nineteen cases showed a rearrangement of the gene coding for the beta chain of the T cell receptor, and in one case a clonal rearrangement of immunoglobulin genes was shown (in which the T cell receptor gene was in a germline configuration). These findings indicate that a monoclonal T cell proliferation is present in most cases of angioimmunoblastic lymphadenopathy, and they also correlate with the fact that some patients who present with this disorder subsequently develop a T cell lymphoma.     

Gender differences in the association between cardiovascular reactivity and aggressive conduct.

The purpose of the present investigation was to examine the association between cardiovascular reactivity to provocation and physically and relationally aggressive conduct. Blood pressure and heart rate were assessed among seventy-seven 5th-grade participants during a period of rest and while discussing a relational provocation. In addition, teachers reported on participants' physically and relationally aggressive behavior. Results provided support for the hypothesis that heightened cardiac reactivity to provocation would be associated with relational forms of aggression among girls. In contrast, for boys, lower cardiac reactivity was associated with physical aggression. These results suggest that the association between cardiovascular reactivity and aggression differs for males and females and that reactivity following relational provocation may be an especially important predictor of relational aggression among girls. Implications for interventions among aggressive children are discussed.     

Epidemiological aids to clinical decision making in primary open angle glaucoma

We have described the epidemiological analysis of one aspect of the King's College Hospital computerised data base; namely initial intraocular pressure as an indicator of visual field loss. The methods involved the use of the four-fold table to determine sensitivity and specificity at different pressure levels. From these results (1) the changes in the pre and post test probability of field loss are calculated and (2) a sensitivity/specificity trade off curve or decision curve is constructed. In this way the optimal cut-off level or operating point for a population of specific type and composition can be determined. The factors concerned in decision making are always complex but such an approach allows a rational and quantifiable alternative to reliance on clinical impression and intuition. The results have significance in relation to decisions on the management of patients and on population screening programmes for glaucoma.     

Effect of exercise on ventricular response to atrial fibrillation in Wolff-Parkinson-White syndrome

Ten patients with Wolff-Parkinson-White syndrome underwent cardiac electrophysiological study extended to include the induction of atrial fibrillation at maximum exercise in the upright position. This was performed using a new temporary bipolar lead with a helical active fixation tip for atrial pacing. The highest rate of atrioventricular conduction via the accessory pathway was greater during exercise than at rest in all 10 patients (mean increase 28%). In three cases the resulting ventricular rate exceeded 300 beats/min, but no patient had severe symptoms or ventricular arrhythmias. The exercise induced enhancement of accessory pathway conduction may significantly but unpredictably affect the risk from spontaneous atrial fibrillation especially in patients with coronary artery disease or in those taking antiarrhythmic drugs. The test procedure was sufficiently simple and well tolerated to be included in our routine electrophysiological investigation.     

Single lead atrial synchronised pacing in patients with cardiogenic shock after acute myocardial infarction.

A pacing system requiring only a single lead was used to establish atrial synchronised pacing in eight patients with complete atrioventricular block and cardiogenic shock following acute myocardial infarction. Spontaneous atrial activity was sensed through electrodes positioned on the pacing lead and used to trigger ventricular demand pacing. A normal atrioventricular relation could be established in each of these critically ill patients without the complexity of inserting and finding a stable position for an additional atrial sensing lead. Atrial synchronised pacing at the spontaneous sinus rate had distinct haemodynamic advantages compared with conventional ventricular pacing at 100 beats/min. Mean cardiac output for the group was 3.3 1/min with atrial synchronised pacing compared with 2.6 1/min with conventional pacing, a significant difference of 27%. Peak systolic pressure averaged respectively 91 and 73 mm Hg in the two pacing modes. With conventional ventricular pacing a pronounced phasic alteration in blood pressure was observed, dependent on the altering relation of the paced beats to spontaneous atrial activity. Atrial synchronised pacing abolished this effect and resulted in a stable blood pressure at or above the peak pressure achieved with conventional pacing. Atrial synchronised pacing with a single lead system can be established rapidly. This mode of pacing has appreciable and significant haemodynamic superiority over conventional ventricular pacing in patients with cardiogenic shock and atrioventricular block following acute myocardial infarction.     

The E. coli CsgB nucleator of curli assembles to β-sheet oligomers that alter the CsgA fibrillization mechanism

Curli are extracellular proteinaceous functional amyloid aggregates produced by Escherichia coli, Salmonella spp., and other enteric bacteria. Curli mediate host cell adhesion and invasion and play a critical role in biofilm formation. Curli filaments consist of CsgA, the major subunit, and CsgB, the minor subunit. In vitro, purified CsgA and CsgB exhibit intrinsically disordered properties, and both are capable of forming amyloid fibers similar in morphology to those formed in vivo. However, in vivo, CsgA alone cannot form curli fibers, and CsgB is required for filament growth. Thus, we studied the aggregation of CsgA and CsgB both alone and together in vitro to investigate the different roles of CsgA and CsgB in curli formation. We found that though CsgA and CsgB individually are able to self-associate to form aggregates/fibrils, they do so using different mechanisms and with different kinetic behavior. CsgB rapidly forms structured oligomers, whereas CsgA aggregation is slower and appears to proceed through large amorphous aggregates before forming filaments. Substoichiometric concentrations of CsgB induce a change in the mechanism of CsgA aggregation from that of forming amorphous aggregates to that of structured intermediates similar to those of CsgB alone. Oligomeric CsgB accelerated the aggregation of CsgA, in contrast to monomeric CsgB, which had no effect. The structured β-strand oligomers formed by CsgB serve as nucleators for CsgA aggregation. These results provide insights into the formation of curli in vivo, especially the nucleator function of CsgB.