Analysis of the 60 S ribosomal protein L27a (L29) gene of Trypanosoma brucei.

The Trypanosoma brucei gene encoding the 60 S ribosomal protein L27a (L29) homologue has been cloned and characterised. The complete open reading frame encodes a small basic protein of 145 amino acids with a predicted molecular weight of 15,950. The L27a amino acid sequence shares 45-58% identity with other L27a (L29) homologues. Southern blot hybridisation suggests that the gene is present in multiple copies. Northern blot analysis of RNA from three T. brucei life cycle stages show that mRNA levels are two-fold higher in procyclic than in early or late bloodstream stages. This infers that this highly conserved ribosomal protein may play an important role in translational regulation through the life cycle of trypanosomes.

Irreversible corneal decompensation in patients treated with topical dorzolamide.

PURPOSE: To describe irreversible corneal decompensation after topical dorzolamide hydrochloride (Trusopt; Merck and Co, Inc, West Point, Pennsylvania) therapy in nine patients who had histories consistent with corneal endothelial compromise. METHOD: Multicenter review of patients' charts. RESULTS: Nine eyes of nine patients developed overt corneal decompensation after starting topical dorzolamide, a condition that did not resolve with drug cessation. This occurred after 3 to 20 weeks (mean, 7.8) of therapy. All nine patients had undergone intraocular surgery. Eight patients had undergone cataract surgery; three were aphakic and three had posterior chamber intraocular lenses. Two patients had anterior chamber intraocular lenses and also had undergone trabeculectomies. Four patients had undergone penetrating keratoplasties, each case complicated by episodes of corneal allograft rejection that were successfully treated. Two patients had asymptomatic Fuchs endothelial dystrophy. Seven patients have since undergone successful penetrating keratoplasties. CONCLUSION: The reports suggest that dorzolamide can cause irreversible corneal edema in a subset of glaucoma patients with endothelial compromise. The findings suggest a rationale for research into the long-term effects of dorzolamide on the corneal endothelium.

Transscleral diode laser therapy for traumatic cyclodialysis cleft.

This case report describes a new surgical approach for the treatment of cyclodialysis. The treatment of cyclodialysis cleft associated with hypotony is in a period of evolution. In this report, a patient with traumatic cyclodialysis associated with hypotony maculopathy was treated with contact transscleral diode laser therapy to the cleft areas. The contact diode laser therapy resulted in closure of the clefts, reversal of hypotony, and resolution of maculopathy with improvement in vision. The results of this study show that this technique can be less invasive than other surgical options.

Limbus- versus fornix-based conjunctival flaps in combined phacoemulsification and mitomycin C trabeculectomy surgery.

PURPOSE: The authors compared the effectiveness of limbus- and fornix-based conjunctival flaps in patients undergoing combined phacoemulsification, intraocular lens implantation, and mitomycin C trabeculectomy. METHODS: The authors conducted a retrospective review of the records of 52 consecutive eyes of 45 patients who underwent combined surgery with limbus- and fornix-based conjunctival flaps. All surgery was by done by one surgeon on predominantly white patients in a suburban glaucoma subspecialty practice. Seven patients had both limbus- and fornix-based surgery, permitting fellow eye comparisons in these patients. All patients had at least 6 months and a median of 17 months follow-up. None of the eyes that were operated on had undergone intraocular surgery previously. RESULTS: No clinically significant difference in postoperative pressure reduction, bleb survival, or visual acuity was seen between the fornix- and limbus-based groups. Results in the fellow eye comparison subgroups were similar. The mean intraocular pressure decreased from 20.4 mmHg before surgery to a mean of 12.4 mmHg at the last follow-up visit. Forty-seven (90.3%) of 52 eyes had a final best-corrected visual acuity of 20/ 40 or better. Forty eyes (76.9%) no longer needed antiglaucoma medications at the end of follow-up. Five eyes had intraoperative posterior capsule rupture; all of these occurred in the limbus-based group. Shallow serous choroidal effusions were more common in the fornix-based group, but none were clinically significant. No difference in postoperative astigmatism between the limbus- or fornix-based group was seen. Intraoperative pupilloplasty, synechialysis, or postoperative neodymium:YAG capsulotomy had no appreciable effect on final intraocular pressure or bleb survival. Endophthalmitis, aqueous misdirection, or hypotony maculopathy did not develop in any patient. CONCLUSION: The effectiveness of limbus- and fornix-based conjunctival flaps appears to be similar. The limbus-based technique may result in a higher incidence of posterior capsular rupture, but the safety of limbus- and fornix-based flaps is otherwise similar. Combined phacoemulsification and mitomycin C trabeculectomy appears to be safe and effective for treating selected patients with coexisting glaucoma and cataract.

Management of a partial-thickness scleral-flap buttonhole during trabeculectomy.

I report the use of partial-thickness Tenon's-conjunctival tissue in the repair of an intraoperative scleral-flap buttonhole that developed during trabeculectomy using adjunctive mitomycin C.

Ab-interno sclerostomy using a goniodiathermy instrument.

We describe the use of a new instrument designed to create a simultaneous goniopuncture with diathermy using an ab-interno technique. The goniodiathermy ab-interno procedure was first performed on three eyes of three cynomolgus monkeys. Intraocular pressure (IOP) assessment and histologic examination were performed over a 10-day period. A functioning filtration bleb with a patent sclerostomy was achieved in all of the experimental eyes. A pilot study involving four eyes of four glaucoma patients also was performed. Of these four, successful long-term functioning filtration areas with adequate lowering of IOP were achieved in only two. The remaining two required further surgical intervention. Although combining goniopuncture and diathermy into a one-step ab-interno procedure proved successful in the primates studied, the preliminary use of this new instrument as a method of creating a filter in humans raises questions regarding its clinical usefulness.

Sympathetic ophthalmia following neodymium:YAG cyclotherapy.

Neodymium:YAG cyclotherapy has been demonstrated to lower intraocular pressure dramatically in patients with uncontrolled glaucoma, with potentially fewer side-effects than cyclocryotherapy. We report the clinical course and histopathological features of a case of sympathetic ophthalmia occurring soon after YAG cyclotherapy.

Gastrointestinal events in patients prescribed non-steroidal anti-inflammatory drugs: a controlled study using record linkage in Tayside.

The relationship between non-steroidal anti-inflammatory drugs (NSAIDs) and gastrointestinal events has been examined in Tayside by record linkage. From March to October 1983, 57 715 prescriptions for five NSAIDs (ibuprofen, indomethacin, naproxen, Osmosin and piroxicam) were issued to 25 959 patients. Their inpatient morbidity from 1 January 1983 to 31 December 1985 was compared to that of an equal number of control subjects matched for age, sex and general practitioner. Analysis revealed that NSAID takers were more likely to develop disease of the gastrointestinal system (ICD 520-579) and symptoms involving the gastrointestinal system (ICD 787). For females the relative risk was 1.67 and for males 1.28. The difference between NSAID takers and controls increased with age above 60 years and was more pronounced over 70 years. Perforation and haemorrhage of peptic ulcer and gastrointestinal haemorrhage was also higher among NSAID takers after prescription: this difference was dependent upon age but not related to sex. The morbidity of the two groups, control and subsequent NSAID takers, was comparable before the NSAID prescriptions were issued and the control rates remained constant throughout the study.

Introducing a drug formulary to general practice--effects on practice prescribing costs.

A drug formulary comprising 249 preparations of 132 drugs and drug combinations was prepared by the partners in a three-doctor general practice serving more than 5000 patients. No attempt was made to change to generic prescribing nor were repeat prescription drugs altered. Introduction of the formulary in September 1981 was followed by an increase in the proportion of prescriptions containing drugs from the formulary from about 55% to more than 60% for both repeat and non-repeat prescriptions. The proportion of formulary drugs on non-repeat prescriptions reached a maximum of 78% within the first year with the additional influence of information feedback. Over the first year the level of formulary drugs used for both repeat and nonrepeat prescribing levelled off at about 62%. Even with these modest changes, when compared with the costs of general practice prescribing in Scotland as a whole, the introduction of the formulary resulted in savings of approximately 10% within the practice for the mean ingredient costs both per patient and per prescription.

Shock-wave effect on anterior segment structures following experimental neodymium:YAG laser iridectomy.

The short-pulse laser may prove superior to the argon laser in producing noninvasive iridectomies. Little is known of the effects of the laser shock-wave on anterior segment structures adjacent to the iris. To investigate this question, iridectomies were produced in two owl monkeys using a neodymium (Nd):YAG laser and tissues were evaluated by light microscopy and scanning and transmission electron microscopy. For purposes of comparison, one eye received an iridectomy produced by an argon laser. Results indicate that while clean iris colobomas can be produced with a well-focused Nd:YAG laser, its shock-wave affects tissues in both the trabecular meshwork and corneal endothelium if the iridectomy is located within 0.8 mm of the limbus. No damage to the trabecular meshwork or corneal endothelium was evident after the argon laser iridectomy.

Effect of cataract surgery on intraocular pressure reduction obtained with laser trabeculoplasty.

Thirty-nine eyes of 34 patients with open-angle glaucoma who had been treated successfully with argon laser trabeculoplasty underwent either extracapsular cataract extraction with posterior chamber intraocular lens implantation or intracapsular cataract extraction without lens implantation. Cataract surgery did not have a significant effect on the magnitude of intraocular pressure reduction obtained with laser trabeculoplasty. This study supports the view that eyes with coexisting cataract and glaucoma may benefit from laser trabeculoplasty before cataract surgery.

Anterior chamber washout for traumatic hyphema.

A surgical approach that involves paracentesis and gentle anterior chamber washout and minimal surgical trauma is presented for dealing with traumatic hyphema. This technique taught by Dr. Paul Chandler produces excellent results and is safe, simple, and without need for elaborate instrumentation.

Effect of pilocarpine in treatment of intraocular pressure elevation following neodymium: YAG laser posterior capsulotomy.

A prospective study was conducted in 30 eyes of 30 patients to determine if pilocarpine would prevent increased intraocular pressure following Q-switched neodymium (Nd):YAG laser posterior capsulotomy. Fifteen eyes were given pilocarpine 4%, immediately following laser therapy and every hour until bedtime. Fifteen eyes served as untreated controls. Our results show that without prophylactic therapy, 10 of 15 eyes (67%) had a post-laser intraocular pressure (IOP) elevation of greater than 10 mmHg, while only one of 15 (6.6%) of the pilocarpine-treated eyes had a rise of that magnitude. The facility of outflow was reduced by 42% in the untreated eyes in contrast to an increase of 3% in those eyes treated with pilocarpine. Thus, pilocarpine 4% is effective in reducing the incidence and magnitude of elevated IOP following Nd:YAG posterior capsulotomy.

Laser trabeculoplasty re-treatment.

Because of inadequate control of intraocular pressure, 26 eyes of 24 patients with primary and secondary open-angle glaucoma who had previously undergone argon laser trabeculoplasty were re-treated. Re-treatment was successful in ten eyes (38%); their average decrease in intraocular pressure was 10.2 mm Hg. After laser re-treatment, three eyes (12%) had marked increases in intraocular pressure, ranging from 10 to 37 mm Hg above baseline, necessitating urgent surgical intervention.

Postmarketing drug surveillance by record linkage in Tayside.

The feasibility of conducting postmarketing drug surveillance by record linkage in Tayside was assessed. The key feature of the method is that all hospital discharge data are already computerised by the area health board and may be accessed through the unique community health number (CHNo) which has been allocated to all Tayside residents. The 12 861 prescriptions for cimetidine dispensed in Tayside over a nine month period were collected and the CHNo identified for 76%. These corresponded to 3802 individuals and their discharge data, together with those for an equal number of controls matched by age, sex, and general practitioner were retrieved from the computer. The expected excess of those diseases for which cimetidine is prescribed (peptic ulcer and oesophagitis) was observed. Other drug-disease associations were observed but may have been due to confounding and emphasise the inadequacy of community based controls. The major advantages of record linkage are, firstly, the low cost of the method, the present study costing just over pounds 12 000, and, secondly, the duration of patient follow up which may may be extended for as many years as required simply by rerunning the computer programs. To assemble large patient cohorts the study would have to be extended to other area health boards that are currently developing similar computer systems. Record linkage may provide a cost effective method for the follow up of patients to identify serious adverse drug reactions, particularly those that take several years to develop.