Combination of bright light and caffeine as a countermeasure for impaired alertness and performance during extended sleep deprivation

Effects of four conditions (Dim Light-Placebo, Dim Light-Caffeine, Bright Light-Placebo and Bright Light-Caffeine) on alertness, and performance were studied during the night-time hours across 45.5 h of sleep deprivation. Caffeine (200 mg) was administered at 20.00 and 02.00 hours and bright-light exposure (>2000 lux) was from 20.00 to 08.00 hours each night. The three treatment conditions, compared to the Dim Light-Placebo condition, enhanced night-time performance. Further, the combined treatment of caffeine and all-night bright light (Bright Light-Caffeine) enhanced performance to a larger degree than either the Dim Light-Caffeine or the Bright Light-Placebo condition. Beneficial effects of the treatments on performance were largest during the early morning hours (e.g. after 02.00 hours) when performance in the Dim Light-Placebo group was at its worst. Notably, the Bright Light-Caffeine condition was able to overcome the circadian drop in performance for most tasks measured. Both caffeine conditions improved objective alertness on the Maintenance of Wakefulness Test. Taken together, the above results suggest that the combined treatment of bright light and caffeine provides an effective intervention for enhancing alertness and performance during sleep loss.     

HERPES SIMPLEX VIRUS TYPE 2 IN BRAZIL: SEROEPIDEMIOLOGIC SURVEY

Background. The incidence of genital herpes is increasing worldwide. Herpes simplex virus type 2 (HSV–2) is the most common cause of genital ulcerations among the sexually transmitted diseases (STDS). In order to investigate the sexual transmission of genital herpes infection in Brazil, the prevalence of specific antibodies to HSV-2, in populations of high and low risk for STDS was evaluated. Methods. The population at low risk for STDS was composed of 155 voluntary blood donors at the University Hospitals between February and August, 1994. The population at high risk for STDS was composed of 85 HIV-seropositive persons, consisting of homosexual and promiscuous heterosexual men. A group of 20 highly active prostitutes was also studied between May and July, 1994. All blood samples were screened using an enzyme-linked immunosorbent assay (ELISA) that detects type-specific antibodies to HSV–2 glycoprotein G. Before donating blood, all persons in the study group were given a questionnaire concerning risk factors for acquisition of STDS and suitable to show the socioepidemiologic characteristics of the subjects. Results. The prevalence of ELISA showing HSV–2 infections among HIV-seroposite persons, was 73% (P < 0.01). In the whole group at high risk for STDS, the prevalence was 72% (P < 0.05). Infection with HSV-2, as determined by seroprevalence, was significantly and independently associated with years of sexual activity, history of previous STDS, number of sexual partners in the previous month, number of pregnancies, and previous induced abortions, as well as the percentage of sexual acts involving receptive anal intercourse.     

Comparative effect of truncal vagotomy and pirenzepine on postprandial secretory response of exocrine pancreas in dogs

The comparative effect of truncal vagotomy and associated pyloroplasty and orally administrated pirenzepine (75 mg, 1 h before food intake) on the exocrine pancreatic secretory response to food was studied in conscious dogs. Both pirenzepine administration and truncal vagotomy totally abolished the pancreatic hydromineral and organic secretory response to food intake while postprandial pH of intraduodenal content remained above 6. From the results of our study we conclude that the vago nerve must not be altered in order to assure a pancreatic response to food intake and that pirenzepine is as strong as truncal vagotomy in maintaining pH in postprandial intraduodenal content over 6.     

Dominantly inherited posterior subcapsular cataract

We report on a family in which many family members show dominantly inherited posterior subcapsular cataract (PSC). While PSC is not a particularly uncommon finding, especially from the influence of congenital, systemic disease, ocular disease and toxic factors, reports of genetically determined PSC are comparatively few in the ophthalmic literature.     

Effect of Enflurane, Isoflurane, and Halothane on Pacing Stimulation Thresholds in Man

Volatile anesthetic agents are often used in patients who require temporary epicardial pacing after cardiopulmonary bypass (CPB). However, the effect of anesthetic agents on energy stimulation thresholds is unknown. After CPB, 24 patients under diazepam-narcotic-pancuronium anesthesia ventilated with an FIO2 = 1.0 received equipotent concentrations of either enflurane, isoflurane, or halothane. Using temporary epicardial electrodes, energy stimulation thresholds were calculated using the data derived from a pacing systems analyzer. Volatile anesthetics do not change energy stimulation thresholds from those already present under diazepam-narcotic-pancuronium anesthesia.     

TWENTY YEARS' EXPERIENCE OF MYOCARDIAL INFARCTION: THE VALUE OF A HEART ATTACK REGISTER

SUMMARY Registers of disease serve a multitude of purposes, but are of particular importance to those interested in audit, in monitoring the introduction of new treatment or training programmes, in health service research, and in the planning of hospital services. The Nottingham Heart Attack Register has been in operation since 1973 and is proving to be an important data source. We present a brief history of the Register, describe how to set up a disease register and demonstrate how it can be of value to a wide range of health service staff using examples from our experience.     

Lactoferrin decreases monocyte-induced fibroblast production of myeloid colony-stimulating activity by suppressing monocyte release of interleukin-1

Lactoferrin (Lf) is a negative regulator of myelopoiesis which operates by suppressing the release from mononuclear phagocytes of GM colony- stimulating factor (GM-CSF) or monokines which can then induce the release of GM-CSA from accessory cells. In this study, endotoxin- depleted, purified iron-saturated human Lf was assessed for its effect on the production of interleukin-1 by cultured monocytes and their subsequent effect on colony-stimulating factor release from cultured fibroblasts. Monocytes were grown with or without Lf and Lf that had previously been incubated with monoclonal anti-Lf. The monocyte- conditioned medium was then either assayed for the presence of interleukin-1 (IL-1) with an enzyme-linked immunosorbent assay or for its ability to stimulate fibroblasts to release growth factors for CFU- GM, BFU-E, or CFU-Mix colonies. In the presence of Lf (10(-7) or 10(-8) mol/L), GM colony-stimulating activity (GM-CSA) was suppressed by 31% to 73%, whereas stimulating activities for BFU-E and CFU-mix colony formation were suppressed by 93% to 100%. Antibody to Lf completely abrogated the suppressive effects observed with Lf, whereas antibody to IL-1 ablated the induction by monocyte-conditioned medium of CSA release by fibroblasts. Lf at 10(-7) and 10(-8) mol/L also reduced IL-1 synthesis by cultured monocytes from 60% to 77%. The inhibitory effects of Lf were only observed when Lf was added before adherence of the monocytes for culture. If Lf was added at the time of adherence or after adherence, no suppression was observed. We conclude that the inhibition of GM-CSA production/release by Lf is mediated through inhibition of the synthesis/release of IL-1 by mononuclear phagocytes. This inhibition of IL-1 prevents accessory cells from producing and/or releasing GM-CSA.