Use of reminders to increase compliance with tetanus booster vaccination.

OBJECTIVE: To assess the effect of three computerized reminder systems on compliance with tetanus vaccination. DESIGN: Prospective randomized controlled trial. SETTING: Ottawa Civic Hospital Family Medicine Centre. PARTICIPANTS: Of 8069 patients 20 years of age or more who were not in a hospital or institution 5589 were randomly assigned, by family, to a control group, a physician reminder group, a telephone reminder group or a letter reminder group. The remaining 2480 patients were not included in the randomized portion of the study but were monitored. Results are presented for the 5242 randomized patients and the 2369 nonrandomized patients for whom there was no up-to-date record of tetanus vaccination at the start of the trial. INTERVENTIONS: For the patients in the physician reminder group the physician was reminded at an office visit to assess the patient''s tetanus vaccination status and to recommend vaccination; those in the other two reminder groups received a telephone call or letter enquiring about their tetanus vaccination status and recommending a booster dose. MAIN OUTCOME MEASURE: Proportion of patients who received tetanus toxoid during the study year or who had a claim of vaccination in the previous 10 years. MAIN RESULTS: The rate of recorded tetanus vaccination in the randomized control group was 3.2%. The difference between that rate and those for the three reminder groups was 19.6% in the physician reminder group (95% confidence interval [CI] 17.1% to 22.2%, p less than 0.00001), 20.8% in the telephone reminder group (95% CI 18.3% to 23.5%, p less than 0.00001) and 27.4% in the letter reminder group (95% CI 24.8% to 30.2%, p less than 0.00001)). The letter reminders were more effective than either the telephone reminders (p = 0.00013) or the physician reminders (p less than 0.00001) in improving compliance. The cost to the practice per additional vaccination recorded was 43 for the physician reminders, $5.43 for the telephone reminders and $6.05 for the letter reminders. CONCLUSIONS: Although all three reminder systems increased the rate of recorded tetanus vaccination they fell far short of achieving complete population coverage. More intensive interventions would be required to approach that goal. However, such interventions do not appear to be justified given the rarity of tetanus.     

A random sequencing approach for placing markers on the physical map of Mycoplasma genitalium.

A physical map of the Mycoplasma genitalium genome has been prepared using pulsed-field gel electrophoresis. This report details recent efforts made to add markers or specific loci to this map in the absence of any mutants or system of genetic exchange. A total of 44 random clones were partially sequenced. Computer analysis was performed in an attempt to identify homologies with genes already recorded in the DNA sequence database. Clones with a large extent of homology to genes from other microorganisms have been assigned to specific loci on the M. genitalium map by hybridization to selected restriction digests. The additional data has facilitated an updated version of the physical map, and verified this random sequencing method as a useful mapping procedure as well as offering new insight into the physiological processes of this fastidious organism.     

Aromatase: Neuromodulator in the control of behavior

Estrogens are required for both the organization of the brain in early development and adult behavior. Two approaches have been used in our laboratory to study the behavioral role of brain aromatase. First, brain metabolism of testosterone (T) has been related to behavior in the same individual using a well established neuroendocrine model, the ring dove, in which estradiol-17β (E₂) has specific effects on brain mechanisms of male behavior. Aromatase in preoptic area (POA) (a) has a high activity (V_max) and strong substrate binding affinity (K_m < 5 nM), (b) is regulated by both androgens and estrogens, and the type of regulation differs according to brain area, (c) is influenced by products of an endogenous inactivating pathway, 5β-reduction; 5β-dihydrotestosterone and other 5β-reduced metabolites appear to be non-genomic regulators of the brain aromatase. Preoptic aromatase activity is also influenced by photoperiod and socio-sexual stimuli. The codistribution of regulated aromatase activity and estrogen receptor cells is found to be T-dependent. Our second approach has been to relate the aromatase system to developmental sex differences in brain structure and behavior of the Mongolian gerbil. Neonatal gerbil aromatase is relatively active in the POA, but has a weaker T substrate-binding affinity (K_m = 30 nM) than the dove. T acting via its metabolite, E₂, masculinizes the sexually dimorphic area of the hypothalamus; the differentiating effect is asymmetric. We suggest that the regulation of the brain aromatase system may be lateralized during steroid-sensitive periods of development.     

Intronic gene conversion in the evolution of human X-linked color vision genes

Human red and green visual pigment genes are X-linked duplicate genes. To study their evolutionary history, introns 2 and 4 (1,987 and 1,552 bp, respectively) of human red and green pigment genes were sequenced. Surprisingly, we found that intron 4 sequences of these two genes are identical and that the intron 2 sequences differ by only 0.3%. The low divergences are unexpected because the duplication event producing the two genes is believed to have occurred before the separation of the human and Old World monkey (OWM) lineages. Indeed, the divergences in the two introns are significantly lower than both the synonymous divergence (3.2% +/- 1.1%) and the nonsynonymous divergence (2.0% +/- 0.5%) in the coding sequences (exons 1-6). A comparison of partial sequences of exons 4 and 5 of human and OWM red and green pigment genes supports the hypothesis that the gene duplication occurred before the human-OWM split. In conclusion, the high similarities in the two intron sequences might be due to very recent gene conversion, probably during evolution of the human lineage.      

The nucleotide sequence of bacteriophage φX174

The complete nucleotide sequence of the DNA of bacteriophage φX174 has been determined. The provisional sequence (Sanger et al., 1977a) deduced largely by the plus and minus method, has been completed and confirmed, predominantly using the terminator method (Sanger et al., 1977b). About 30 revisions were found to be necessary in the 5386-nucleotide sequence. The amino acid sequences of the ten proteins for which the DNA codes have also been deduced.     

Analyses of Livestock Production, Waste Storage, and Pathogen Levels and Prevalences in Farm Manures

Survey results describing the levels and prevalences of zoonotic agents in 1,549 livestock waste samples were analyzed for significance with livestock husbandry and farm waste management practices. Statistical analyses of survey data showed that livestock groups containing calves of <3 months of age, piglets, or lambs had higher prevalences and levels of Campylobacter spp. and Escherichia coli O157 in their wastes. Younger calves that were still receiving milk, however, had significantly lower levels and prevalence of E. coli O157. Furthermore, when wastes contained any form of bedding, they had lowered prevalences and levels of both pathogenic Listeria spp. and Campylobacter spp. Livestock wastes generated by stock consuming a diet composed principally of grass were less likely to harbor E. coli O157 or Salmonella spp. Stocking density did not appear to influence either the levels or prevalences of bacterial pathogens. Significant seasonal differences in prevalences were detected in cattle wastes; Listeria spp. were more likely to be isolated in March to June, and E. coli O157 was more likely to be found in May and June. Factors such as livestock diet and age also had significant influence on the levels and prevalences of some zoonotic agents in livestock wastes. A number of the correlations identified could be used as the basis of a best-practice disposal document for farmers, thereby lowering the microbiological risks associated with applying manures of contaminated livestock to land.     

Implementing reduced-risk integrated pest management in fresh-market cabbage: improved net returns via scouting and timing of effective control

During 1998-2001, field studies were done to assess the efficacy of an integrated pest management (IPM) program using an action threshold and "reduced-risk" insecticides. The IPM program was compared with a conventional grower-based program. Program performance was evaluated based on management of Trichoplusia ni (Hiibner), Pieris (=Artogeia) rapae (L.), and Plutella xylostella (L.), as well as the economic impact of each program on net returns. The action threshold used in the IPM program consisted of 10% plants infested with T. ni larvae, based on previous small-plot experiment station trials. In all years of the study, the IPM program resulted in significantly lower percentages of plants infested than the conventional program or untreated check. The mean reduction in insecticide applications for the IPM program compared with the conventional program was 23.5%, whereas, on average, the costs of the IPM program were 46.0% higher than the conventional program. Pest reduction in the IPM program resulted in an average of 10.5% higher marketable yields than the conventional program. Percentages of marketable heads in the IPM program ranged from 82 to 99% and from 63 to 96% in the conventional program. Mean net returns for the IPM program exceeded the conventional program by $984.20/ha. These results indicated that the IPM program reduced insecticide use overall, even though costs of the IPM program, with either spinosad or indoxacarb, were sometimes higher. Overall, net returns of the IPM program were higher due to active pest scouting, improved application timing, and increases in marketable yield. Given the potential decrease in insecticide applications and increases in net profit resulting from this IPM program, additional analyses should be conducted to quantify the economic risk, or consistency of the results, to fully evaluate the benefits of the IPM program compared with a conventional program.