Effect of superficial heat, deep heat, and active exercise warm-up on the extensibility of the plantar flexors.

BACKGROUND AND PURPOSE: Warm-up prior to static stretching enhances muscle extensibility. The relative effectiveness of different modes of warm-up, however, is unknown. The purpose of this study was to evaluate the effectiveness of superficial heat, deep heat, and active exercise warm-up prior to stretching compared with stretching alone on the extensibility of the plantar-flexor muscles. SUBJECTS: Ninety-seven subjects (59 women, 38 men) with limited dorsiflexion range of motion (ROM) were randomly assigned to 1 of 5 groups. Female subjects had a mean age of 27.6 years (SD=7.68, range=17-50), and male subjects had a mean age of 26.8 years (SD=6.87, range=18-48). METHODS: The first group (group 1) was a control group and did not perform the stretching protocol. The 4 experimental groups (groups 2-5) performed a stretching protocol 3 days per week for 6 weeks. Group 2 performed the static stretching protocol only; group 3 performed active heel raises before stretching; group 4 received 15 minutes of superficial, moist heat to the plantar-flexor muscles before stretching; and group 5 received continuous ultrasound for 7 minutes before stretching. Dorsiflexion ROM measurements were taken initially and after 2, 4, and 6 weeks. RESULTS: All experimental groups increased active and passive range of motion (AROM and PROM). The mean AROM/PROM differences at 6 weeks were 1.11/1.39 degrees for group 1, 4.10/6.11 degrees for group 2, 4.16/4.21 degrees for group 3, 4.38/4.90 degrees for group 4, and 6.20/7.35 degrees for group 5. The group receiving ultrasound before performing the stretching protocol (group 5) displayed the greatest increase in both AROM (6.20() and PROM (7.35(). DISCUSSION AND CONCLUSION: Among the modalities tested, the use of ultrasound for 7 minutes prior to stretching may be the most effective for increasing ankle dorsiflexion ROM.

Polymerase chain reaction assay to identify all immature stages of two species of the Anopheles quadrimaculatus sibling species complex (Diptera: Culicidae).

A polymerase chain reaction assay that detects differences in the 2nd internal transcribed spacer of ribosomal DNA was tested as a means to identify all immature stages of 2 species in the Anopheles quadrimaculatus sibling species complex. The technique was successful in amplifying DNA from eggs, 1st-4th instars, and pupae of An. quadrilmaculatus Say and An. inundatus Reinert.

Comparison of electrostatic versus nonelectrostatic ULV sprays of Aqua Reslin against Anopheles quadrimaculatus adults.

An electrostatic truck-mounted spray system (Spectrum, Houston, TX) and a nonelectrostatic spray system (Micro-Gen G-4, San Antonio, TX) were tested to determine the feasibility of electrostatically charging Aqua Reslin, a water-based permethrin insecticide, and ascertain whether an electrostatic charge would increase the efficiency of Aqua Reslin against Anopheles quadrimaculatus adults. Parameters tested for both machines included mean mass median diameter (MMD) of droplets, number of drops per cm2, and posttreatment percent mortality at 1, 12, and 24 h. Results indicated that the electrostatically charged droplets produced greater mortality at each distance and hour posttreatment. Correlation coefficients and linear equations were calculated for distance-mortality, MMD-mortality, drops per cm2-mortality, distance-drops per cm2, distance-MMD, and MMD-drops per cm2. Results indicated that the electrostatic drops demonstrated strong correlations between each paired variable, whereas the nonelectrostatic drops showed poor correlation between drops per cm2-mortality, distance-drops per cm2, and MMD-drops per cm2. However, from this trial, these differences cannot be attributed purely to the electrostatic charge because significant differences in droplet size can affect spray performance.

Mosquito (Diptera: Culicidae) host compatibility and vector competency for the human myositic parasite Trachipleistophora hominis (Phylum Microspora).

Microsporidian spores of Trachipleistophora hominis Hollister, isolated from a human, readily infected larval stages of both Anopheles quadrimaculatus Say sensu lato and Culex quinque-fasciatus Say. Mosquito infections with T. hominis were located, primarily, in abdominal muscles in segment numbers 4 through 6; other spores were found in the hemocoel and proboscis. Nearly 50% of the infected mosquito larvae survived to the adult stage. Spores recovered from adult mosquitoes were inoculated into mice and resulted in significant muscle infection at the site of injection. Preliminary observations also showed that T. hominis spores can be passively transferred from infected mosquitoes to a sugar water substrate.

Validation of a ribosomal DNA-polymerase chain reaction species diagnostic assay for the common malaria mosquito (Diptera:Culicidae) sibling species complex.

A polymerase chain reaction method for identifying individuals in the Anopheles quadrimaculatus Say sibling species complex was validated for wild mosquitoes from Louisiana and Mississippi. This method distinguished An. quadrimaculatus species A, B, C, and D by detecting species-specific differences in the 2nd internal transcribed spacer of ribosomal DNA and was 100% specific and 95% sensitive.

Record of Anopheles quadrimaculatus species C in Louisiana.

Sibling species C of the Anopheles quadrimaculatus species complex was found south of Abbeville (Vermilion Parish), Louisiana, during a state-wide survey in 1993. This constitutes a new state record and currently represents its westernmost distribution.