Ultrasound characteristics of the deep abdominal muscles during the active straight leg raise test.

OBJECTIVE: To determine whether changes in the transversus abdominis (TrA) and internal oblique (IO) muscles, as seen on ultrasound imaging, during the active straight leg raise (ASLR) test differ between subjects with and without unilateral lumbopelvic pain. DESIGN: Cross-sectional, case-control study. SETTING: Clinical laboratory. PARTICIPANTS: Subjects (n=15) with unilateral symptoms in the lumbopelvic region and age-matched and sex-matched control subjects (n=15). INTERVENTIONS: Bilateral measurements of the deep abdominal muscles (TrA and IO) were obtained simultaneously using ultrasound imaging to compare the percent change in muscle thickness from rest with (1) immediately on raising, (2) after a 10-second hold, and (3) within 5 seconds after returning the lower extremity to the plinth. MAIN OUTCOME MEASURE: Percent change in muscle thickness of both muscles from rest to the other 3 time intervals during the ASLR test. RESULTS: The 3-way group x side measured x time and 2-way side measured x time interactions were not significant for either the TrA (P> or =.34) or the IO (P> or =.14) muscles. The 2-way interaction group x time was significant for both the TrA (P=.003) and the IO (P=.02) muscles. On lifting the lower extremity, the control group demonstrated a 23.7% and 11.2% increase in TrA and IO muscle thickness, respectively, while those with lumbopelvic pain demonstrated a 6.4% and 5.7% increase in TrA and IO muscle thickness, respectively. CONCLUSIONS: Although subjects with unilateral lumbopelvic pain demonstrated a smaller increase in muscle thickness, during the ASLR test there appears to be a symmetrical response in both of the deep abdominal muscles regardless of which lower extremity is lifted during the ASLR test or the unilateral nature of the symptoms. This study attests to the potential construct validity of using the ASLR test to assess different motor control strategies of the TrA and IO muscles in subjects with unilateral lumbopelvic pain.

A variable partially polarizing beam splitter.

We present designs for variably polarizing beam splitters. These are beam splitters allowing the complete and independent control of the horizontal and vertical polarization splitting ratios. They have quantum optics and quantum information applications, such as quantum logic gates for quantum computing and non-local measurements for quantum state estimation. At the heart of each design is an interferometer. We experimentally demonstrate one particular implementation, a displaced Sagnac interferometer configuration, that provides an inherent instability to air currents and vibrations. Furthermore, this design does not require any custom-made optics but only common components which can be easily found in an optics laboratory.

Platelet-rich plasma: clinical applications in dentistry.

BACKGROUND: Platelet-rich plasma, or PRP, has become a valuable adjunct in wound healing in dentistry. Postsurgically, blood clots initiate the healing and regeneration of hard and soft tissues. Clinicians and scientists are investigating the use of PRP in dentistry as a way to enhance the body's natural wound-healing mechanisms. TYPES OF ARTICLES REVIEWED: The authors reviewed scientific articles that discuss the basic knowledge of wound healing mechanisms and that directly studied the growth factors shown to be concentrated in PRP. They also reviewed articles written by clinicians and researchers in dentistry fields, including oral and maxillofacial surgery and periodontics to determine applications of PRP in the field of dentistry. RESULTS: All of the reviewed articles expressed promise in PRP use and in the growth factors expressed by the platelets concentrated in PRP-namely platelet-derived growth factor, or PDGF, and transforming growth factor-beta, or TGF-beta--as an adjunct to postsurgical wound healing. Both PDGF and TGF-beta have been shown in vivo to accelerate wound healing through different mechanisms. The development of an autologous PRP has been shown to be relatively easy, to be effective as a surgical adjunct, to retain high levels of the desired growth factors after preparation and to be clinically effective in accelerating postsurgical healing in both periodontal and oral surgery applications. CLINICAL IMPLICATIONS: PRP has proven to be effective at improving surgical results in a variety of procedures in the field of oral and maxillofacial surgery. PRP also shows promise in periodontal regenerative therapy and should continue to be studied by scientists and clinicians alike.

Hypovitaminosis D correction and high-sensitivity C-reactive protein levels in hypertensive adults.

CONTEXT: Hypovitaminosis D has been implicated as a possible risk factor for the development of cardiovascular disease. High-sensitivity C-reactive protein (hs-CRP) has been one of the most extensively studied biomarkers for cardiovascular inflammation as an indicator of disease and event risk, independent of traditional risk factors. To date, it is unclear if correction of hypovitaminosis D leads to a reduction of hs-CRP in human subjects. OBJECTIVES: To assess laboratory validity of 25-hydroxyvita-min D (25-OH-vitamin D) and hs-CRP measurements and to determine whether hs-CRP levels in adults with well-controlled hypertension and comorbid low vitamin D levels changed after hypovitaminosis D correction to a serum 25-OH-vitamin D level greater than 30 ng/mL. DESIGN: Prospective study using an unblinded design. RESULTS: One hundred eight subjects who were vitamin D insufficient or deficient completed this study. The mean 25-OH-vitamin D level was 20.07 ng/mL before treatment and 43.92 ng/mL after treatment. Posttreatment vitamin D levels were in the normal range for 91% of the subjects. No statistically significant changes in hs-CRP level were detected after the vitamin D treatment was administered and a posttreatment vitamin D level above 30 ng/mL was confirmed. CONCLUSION: We did not detect a statistically significant difference in hs-CRP after correction of hypovitaminosis D. Twelve weekly oral doses of 50,000 IU of ergocalciferol corrected the hypovitaminosis D in more than 90% of cases.