In vitro and in vivo bactericidal activities of 10%, 2.5%, and 1% povidone-iodine solution

The bactericidal action of three formulations of a povidone-iodine (PVI) complex in vitro, in vivo, and in the presence of competing organic matter was evaluated. Bacterial organisms included Staphylococcus aureus ATCC 25923 and 25 clinical isolates of Staph. aureus, designated KU 1-25. For the in vitro studies, 1.0 mL of bacterial inoculum containing 10(7) organisms was introduced into 9.0 mL of chemically stable 10% and 1% PVI formulations in sterile culture tubes, and 1.0-mL samples were withdrawn at set intervals. Samples were plated by using standard techniques and incubated for 24 hours, after which colony-forming units were counted. For in vivo studies, 0.1 mL of 10(6) Staph. aureus ATCC 25923 or KU inoculum was deposited on the dorsum of the hand of healthy human subjects. This area was wiped with a cotton swab saturated with 1%, 2.5%, or 10% PVI formulations. Samples were taken at 15 and 30 seconds after application of the iodophor. To test the bactericidal activity of the three formulations in the presence of a competing substrate, a swab soaked with sterile sheep's blood was applied to the skin and allowed to dry. The percentage of 10(4) Staph. aureus inoculum recovered allowed for comparison of the three products. In vitro, the 1% PVI formulation was bactericidal for 10(7) Staph. aureus within two minutes, as compared with the four minutes required by 10% PVI. On the skin contaminated with 10(6) organisms, the rates of killing within 30 seconds were comparable for both solutions.(ABSTRACT TRUNCATED AT 250 WORDS)     

Confinement induces actin flow in a meiotic cytoplasm

In vivo, F-actin flows are observed at different cell life stages and participate in various developmental processes during asymmetric divisions in vertebrate oocytes, cell migration, or wound healing. Here, we show that confinement has a dramatic effect on F-actin spatiotemporal organization. We reconstitute in vitro the spontaneous generation of F-actin flow using Xenopus meiotic extracts artificially confined within a geometry mimicking the cell boundary. Perturbations of actin polymerization kinetics or F-actin nucleation sites strongly modify the network flow dynamics. A combination of quantitative image analysis and biochemical perturbations shows that both spatial localization of F-actin nucleators and actin turnover play a decisive role in generating flow. Interestingly, our in vitro assay recapitulates several symmetry-breaking processes observed in oocytes and early embryonic cells.     

Spinal radiation before surgical decompression adversely affects outcomes of surgery for symptomatic metastatic spinal cord compression

STUDY DESIGN: A retrospective chart review was performed. OBJECTIVE: To determine whether preoperative spinal radiation increases the number of major wound complications in patients with cancer who have symptomatic spinal cord compression. SUMMARY OF BACKGROUND DATA: Many factors have increased the number of patients hospitalized with symptomatic spinal cord compression after spinal irradiation. The surgical management of metastatic spinal cord compression may be complicated by preoperative radiation. METHODS: A retrospective review of 123 patients admitted with symptomatic metastatic spinal cord compression from 1970 through 1996 was conducted. The final study population of 85 patients was separated into three treatment groups: 1) radiation only, 2) radiation followed by surgery, and 3) de novo surgery followed by radiation. RESULTS: The major wound complication rate for patients who had radiation before surgical decompression and stabilization was 32%, or threefold, higher than the 12% observed in patients who had de novo surgery (P < 0.05). No other clinical factor or condition predicted the development of a major wound complication. Patients treated initially with surgery had superior functional outcomes in an analysis stratified by Frankel grade (P < 0.05). Of the ambulatory patients who underwent de novo surgery, 75% remained ambulatory and continent 30 days after treatment, whereas only 50% of those treated with radiation before surgery had similar outcomes. CONCLUSIONS: Spinal radiation before surgical decompression for metastatic spinal cord compression is associated with a significantly higher major wound complication rate. In addition, preoperative spinal irradiation might adversely affect the surgical outcome.     

Occipital Nerve Blockade for Cervicogenic Headache: A Double-Blind Randomized Controlled Clinical Trial

Abstract:   Cervicogenic headache is a chronic hemicranial pain, usually occurring daily. This randomized, double-blind, placebo-controlled trial evaluated the effectiveness of nerve stimulator-guided occipital nerve blockade in the treatment of cervicogenic headache. The reduction in analgesic consumption was the primary outcome measure. Fifty adult patients diagnosed with cervicogenic headache were randomly divided into two equal groups of 25 patients each. All patients in both groups received greater and lesser occipital blocks, whereas only 16 patients in each group received facial nerve blockade in association with the occipital blocks. The control group received injections of an equivalent volume of preservative-free normal saline. Pain was assessed using the visual analog scale (VAS) and the Total Pain Index (TPI). Forty-seven patients entered into the final analysis as three patients were lost to follow-up. Anesthetic block was effective in reducing the VAS and the TPI by approximately 50% from baseline values ( P  = 0.0001). Analgesic consumption, duration of headache and its frequency, nausea, vomiting, photophobia, phonophobia, decreased appetite, and limitations in functional activities were significantly less in block group compared to control group ( P  < 0.05). The nerve stimulator-guided occipital nerve blockade significantly relieved cervicogenic headache and associated symptoms at two weeks following injection.