Ptosis in the rat following topically administered 2% epinephrine.

Commercially available 2% epinephrine instilled twice daily in one eye of 15 rats resulted in ptosis after 4 weeks treatment. The ptosis was indistinguishable from that observed following topical treatment with 6-hydroxydopamine 20% and surgical sympathectomy. Ptosis in both epinephrine- and 6-hydroxydopamine-treated rats was associated with a statistically significant depletion of ocular norepinephrine, as determined by a sensitive catecholamine radio enzyme assay. Ultrastructural evidence of nerve terminal degeneration was present near the smooth muscle of Müller within the eyelid of rats treated with epinephrine. This study provides further evidence epinephrine administration can result in chemical sympathectomy as has been described following 6-hydroxydopamine.

Local ocular hypotensive effect of topically applied acetazolamide.

Acetazolamide's usefulness in the treatment of the glaucomas is limited by the systemic side effects that often accompany its oral administration, and topical administration was initially thought to have no effect upon the intraocular pressures of human and rabbit eyes. Recent studies, however, have shown the usefulness of water-loading tests for screening drugs with potential antiglaucomatous activity. We found evidence that topical acetazolamide has the ability to lessen the increase in intraocular pressure after water-loading in pigmented rabbits and correlated this observation with low levels (0.0 to 0.7 microgram/ml) of plasma acetazolamide. Further, a separate study showed that 10% topical acetazolamide can enhance the ocular hypotensive effects of systemically administered acetazolamide in normal pigmented rabbits, suggesting that topically applied acetazolamide can have a local effect on intraocular pressure.

Photoastigmatic refractive keratectomy in myopes. Nidek US Investigators Group.

PURPOSE: Photoastigmatic refractive keratectomy (PARK) was studied in a multi-center clinical trial. The Nidek EC-5000 excimer laser was evaluated for its effect on refraction, visual acuity, and safety measures as part of a U.S. Food and Drug Administration (FDA) regulated study. METHODS: Eight U.S. centers enrolled adults with eyes having refractive astigmatism up to 4.00 D and a myopic spherical equivalent refraction up to -8.00 D. Results are reported for 749 eyes of 486 patients with at least 6 months follow-up. The rectangular beam scanning Nidek EC-5000 used a 5.5-mm-diameter treatment zone, a 7.0-mm-diameter peripheral blend zone, and a 40 Hz pulse rate for surface treatment of myopic astigmatism. Nomogram corrections to machine settings were required to achieve the desired results. RESULTS: Preoperative average spherical equivalent refraction of -4.90+/-1.74 D was reduced to -0.02+/-0.79 D at 6 months. Refractive stability was established at 3 months. Over 62% of eyes were within +/-0.50 D of desired correction at 6 months, with over 86% within +/-1.00 D. Uncorrected visual acuity improved by an average of 10 Snellen lines; over 64% of eyes saw 20/20 or better uncorrected and over 93% saw 20/40 or better uncorrected at 6 and 12 months. PARK treatment effectively reduced astigmatism with little average axis error or magnitude error. Corneal haze and safety concerns were minimal. CONCLUSIONS: Photoastigmatic refractive keratectomy using the Nidek EC-5000 excimer laser provided significant reduction of myopia and astigmatism, with minimal complications.

Effects of selective cholinergic antagonists and alpha,beta-methylene ATP on guinea-pig urinary bladder contractions in vivo following pelvic nerve stimulation.

1. An in vivo preparation measuring functional detrusor muscle strength in terms of intravesical bladder pressure (Pves) following in situ pelvic nerve stimulation has been developed in urethane-anaesthetized guinea pigs. 2. The increase in bladder pressure following pelvic nerve stimulation was abolished by topical lidocaine or tetrodotoxin, suggesting a neurogenic origin for the in vivo contractile response. 3. Cholinergic antagonists (i.v.) decreased the amplitude of the peak pressure response by about 50% at both high (30 Hz) and low (5 Hz) stimulation rates, with a rank order of potency of atropine greater than propantheline greater than oxybutynin greater than hexahydrosiladifenidol greater than pirenzepine greater than methoctramine. 4. The P2 purine receptor antagonist, alpha,beta-methylene ATP (i.v.), antagonized pelvic nerve-stimulated bladder contractions differentially at 5 and 30 Hz. At low frequencies, alpha, beta-methylene ATP was both more potent (2.5-fold) and more efficacious (-77 compared to -55% delta) than at 30 Hz. Atropine and alpha,beta-methylene ATP together completely inhibited the contractile response. 5. Together, the findings indicate that in guinea pigs, urinary bladder contractions induced by pelvic nerve stimulation in vivo may be mediated by both muscarinic and purinergic receptors and that these bladder contractions may be mediated by the M2 beta subtype rather than by M1 or M2 alpha muscarinic receptors.

Linkage group IV in the Syrian hamster: spontaneous seizure and jute.

It was shown that sz and J are closely linked and that the recombination frequency between these two genes is 7.41 +/- 2.91. It was also shown that J is not linked with markers in linkage groups I and III, and that sz is not linked with a marker in linkage group II. Therefore, linkage between sz and J is a new linkage group. Since only three linkage groups have so far been established in the Syrian hamster, linkage groups I, II and III, this new linkage constitutes linkage group IV.

Comparison of health outcomes among older construction and blue-collar employees in the United States.

Using the Health and Retirement Study, we compare the health outcomes of older male construction workers with their counterparts in other occupations. We find that construction workers are more susceptible to musculoskeletal problems, chronic lung disease, and emotional/psychiatric disorders. Older construction workers were 1.4 times more likely to have a back problem and 1.3 times more likely to have a foot or leg problem than were other blue-collar workers. Nonsmoking older construction workers were 3.2 times more likely to have chronic lung disease than their nonsmoking blue-collar counterparts. When accounting for alcohol consumption, older construction workers were 1.7 times more likely to have been diagnosed with an emotional problem than other older blue-collar workers. The high rate of chronic lung disease is most likely related to on-the-job dust exposure, while the increased risk of emotional disorders might be due to the dynamics of the construction labor market.

In vivo cystometrogram studies in urethane-anesthetized and conscious guinea pigs.

Urinary bladder cystometry using urethral catheters is described in vivo in a urethane-anesthetized guinea pig preparation and compared to an awake-animal preparation in which surgically implanted catheters were used. Anticholinergic drugs dose-dependently inhibited the peak intravesical pressure (PvesP) to a maximum of approximately 80% but had no effect on other cystometrogram (CMG) parameters (threshold pressure, bladder capacity). Stereoselectivity was evident; dexetimide but not levetimide potently depressed PvesP. Oxybutynin was equipotent (ID50 approximately 0.15 mg/kg) in both preparations and showed a similar duration of action (t1/2 = 48-53 min). The data suggests that CMG parameters and the effects of oxybutynin were not affected by urethane anesthesia, making the in vivo urethane-anesthetized guinea pig preparation a valuable tool to evaluate both the filling and voiding phases of cystometry.

Spontaneous seizures: a new mutation in Syrian golden hamsters.

Hereditary spontaneous seizures in the Syrian hamsters are described. The seizures occur in 30 to 60-day-old animals from about 2 to 5 hours. The condition is a simple recessive trait, and the gene symbol sz is proposed.

Loneliness and alcoholism: a study of three groups of male alcoholics.

Three groups of alcoholics at different stages of recovery were tested for loneliness with the Sisenwein Loneliness Scale. The groups consisted of alcoholics going through detoxification (acute), alcoholics in outpatient treatment who had had at least two drinking episodes in the previous 6 months (chronic), and alcoholics having at least 1 year of sobriety (recovering). It was hypothesized that the acute group would exhibit more loneliness than the chronic group, who would in turn demonstrate more loneliness than the recovering group. Results showed that acute group to demonstrate significantly (p less than .01) more loneliness on the Sisenwein (mean = 134.4) than the recovering group (mean = 54.6). The chronic group (mean = 91.0) was not significantly different than the others at the p less than .01 level, but the mean score did fall in the expected direction.

Amiodarone keratopathy and lens opacities.

Amiodarone hydrochloride is an antiarrhythmic drug which produces a keratopathy and anterior subcapsular lens opacities that are usually asymptomatic. Serial observations for eye findings were made in 21 patients on a daily dosage of 200-600 mg for periods ranging from six months to three years. Corneal deposits developed in all 21 patients and anterior lens opacities developed in 12 of 20 phakic patients. Resolving keratopathy was present in three patients for periods of at least seven to 20 months after amiodarone was discontinued.

Anterior subcapsular cataracts: a review of potential etiologies.

Photographs of amiodarone-induced anterior subcapsular lens opacities and axial punctate lens opacities are presented and compared for the first time. The similarities and differences between these lens opacities and phenothiazine-induced lens opacities are discussed. Potential etiologies for anterior subcapsular cataracts are reviewed. The biomicroscopic techniques required to appreciate subtle lens opacities are mentioned. The importance of recognizing and recording subtle lens opacities is discussed.

Mini-pig urinary bladder function: comparisons of in vitro anticholinergic responses and in vivo cystometry with drugs indicated for urinary incontinence.

1. Studies of carbachol-induced contractions on mini-pig bladder tissue strips in vitro demonstrated that antagonist drugs produced a rank order of potency similar to that observed in guinea-pig tissues: propantheline approximately atropine greater than oxybutynin greater than dicyclomine greater than HHSiD greater than imipramine greater than terodiline approximately AF-DX 116. The drugs appeared to show competitive antagonism and the tissues exhibited resistance to complete cholinergic blockade. 2. Cytometry performed in vivo on awake mini-pigs also showed that i.v. cholinergic antagonists produced a dose-dependent depression of peak intravesical bladder pressure (PvesP) during slow filling of the bladder using urethral catheters, with a rank order of potency: atropine greater than oxybutynin approximately propantheline greater than HHSiD approximately dicyclomine greater than terodiline. Other parameters of the cystometrogram were unaffected by the antagonists, except for residual volume, which generally increased after drug treatment. 3. Hexahydrosiladifenidol (HHSiD), an ileal-selective competitive muscarinic antagonist, was about as effective an antagonist as the clinically useful drugs oxybutynin or dicyclomine, both in vitro and in vivo, suggesting that HHSiD may have useful therapeutic effects for the treatment of urinary incontinence. 4. Correlation of the rank order of potency for muscarinic antagonism between mini-pigs and guinea-pigs was very high in vitro (r = 0.97, P less than 0.05), as was the correlation among the drugs for their ability to depress PvesP of the cystometrogram in vivo (r = 0.89, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)