Drought stress enhances the efficiency of floral dip method of Agrobacterium-mediated transformation in Arabidopsis thaliana.

The Agrobacterium-mediated floral dip protocol is the most extensively used transformation method for a model plant Arabidopsis thaliana. Several useful methods for Agrobacterium tumefaciens-mediated transformations of Arabidopsis are existing, but they are time consuming and with low transformation efficiency. Here, we developed a transgenic Arabidopsis lines TET12p::TET12-RFP in a short period of time and enhanced transformation efficiency by using a modified transformation method by applying drought stress after floral dip. In this protocol, Agrobacterium cells carrying TET12p::TET12-RFP recombinant vectors were resuspended in a solution of 5% sucrose, 0.05% (v/v) silwet L-77 to transform female gametes of developing Arabidopsis inflorescences. Treated Arabidopsis were then applied with different levels of drought stresses to stimulate plants for the utilization of maximum plant energy in seed maturation process. The applied stresses achieved the fast maturation of already treated inflorescences while stopped the growing of newly arising untreated inflorescence, thus decreased the chances of wrong collection of untransformed seeds. Consequently, the collected seeds were mostly transgenic with a transformation frequency of at least 10%, thus the screening for positive transformants selection was more advantageous on a selective medium as compared to a classical floral dip method. Within 2-3 months, two hundred of individual transgenic plants were produced from just 10 infiltrated plants. This study concludes that application of drought stresses in a specific stage of plant is a beneficial strategy for achieving the transgenic Arabidopsis in a short period of time with high transformation efficiency.

Clinical and laboratory features of Mycobacterium mageritense.

Six clinical isolates of the nonpigmented, rapidly growing species Mycobacterium mageritense were recovered from sputum, bronchial wash, blood, sinus drainage, and two surgical wound infections from separate patients in Texas, New York, Louisiana, and Florida. The isolates matched the ATCC type strain by PCR restriction enzyme analysis of the 65-kDa hsp gene sequence of Telenti, high-performance liquid chromatography, biochemical reactions, and partial 16S rRNA gene sequencing. These are the first isolates of this species to be described in the United States and the first isolates to be associated with clinical disease. Susceptibility testing of all known isolates of the species revealed all isolates to be susceptible or intermediate to amikacin, cefoxitin, imipenem, and the fluoroquinolones and sulfonamides but resistant to clarithromycin. Because of their phenotypic and clinical similarity to isolates of the Mycobacterium fortuitum third biovariant complex (sorbitol positive), isolates of M. mageritense are likely to go undetected unless selected carbohydrate utilization or molecular identification methods are used.

The effect of vertebral rotation of the lumbar spine on dual energy X-ray absorptiometry measurements: observational study.

OBJECTIVE: To estimate how axial rotation of lumbar vertebrae quantitatively affects bone mineral density, as measured by dual energy X-ray absorptiometry in the anteroposterior plane. DESIGN: Observational study. SETTING: University teaching hospital, Hong Kong. PATIENTS: Cadaver lumbar vertebrae (L2 to L4) were removed from four adults. MAIN OUTCOME MEASURES: Using dual energy X-ray absorptiometry, the bone mineral content, bone area, and bone mineral density were measured in the neutral position and with vertebral axial rotation in increments of 7.5 degrees, up to a maximum of 45 degrees. RESULTS: Correlation analysis showed a significant positive correlation between the degree of rotation and measured bone area, a significant negative correlation between degree of rotation and bone mineral density measurements, but no significant correlation between degree of rotation and measured bone mineral content. The measured bone area increased approximately 24% and the bone mineral density decreased approximately 19% when the vertebrae were rotated by 45 degrees. CONCLUSIONS: These results suggest that for patients with rotational deformity of the spine, such as scoliosis, measurements of lumbar spine bone mineral content by dual energy X-ray absorptiometry is not affected, while bone mineral density measurements are not reliable.

The control of hyperendemic glycopeptide-resistant Enterococcus spp. on a haematology unit by changing antibiotic usage.

The rectal carriage of glycopeptide-resistant Enterococcus spp. (GRE) had been established at approximately 50% in a series of prevalence studies on a busy haematological malignancy unit. The aim of this study was to reduce the chance of patients acquiring GRE. A prospective three-phase sequential study was performed. In Phase 1, the acquisition rate of GRE detectable by rectal swab was measured without any intervention for a period of 4 months. For the following 8 months (Phase 2), the first-line treatment for febrile neutropenic episodes was changed from monotherapy with ceftazidime to piperacillin/tazobactam. In addition, an intense education programme was introduced to improve hygiene to reduce the risk of case-to-case spread. In the final 4 months (Phase 3), ceftazidime was again used as the first-line antimicrobial, while continuing the same level of training in relation to hygiene. The carriage of GRE was measured from rectal swabs done weekly. During the initial 4 months, at any time, 40-50% of patients in the unit were colonized with GRE, and 43 of 75 (57%) new patients initially negative for GRE acquired it within 6 weeks of their admission. In Phase 2, 25 patients out of 129 (19%) acquired GRE, with the acquisition rate falling progressively so that in the last 3 months, only one new patient acquired GRE (logrank comparison of probabilities for cohort 1 vs cohort 2b: P < 0.0001). A return to ceftazidime in Phase 3 was associated with a return of the risk of acquiring detectable GRE colonization, despite continued hygiene teaching and surveillance, with 21 out of 58 patients (36%) acquiring GRE (cohort 1 vs cohort 3: P = 0.08). Glycopeptide usage was not reduced during the period of the study. Clinical cases were seen only in Phases 1 and 3. Although the reduction in the risk of acquiring GRE may have been due in part to hygiene practices as well as to the change in antimicrobial usage, or may have occurred spontaneously for other reasons, the return of the problem with the reintroduction of ceftazidime strongly suggests that this antibiotic was responsible for encouraging the acquisition of detectable GRE.

A multiinstitutional evaluation of the analgesic efficacy and safety of ketorolac tromethamine, acetaminophen plus codeine, and placebo in cancer pain.

Seventy-five patients with moderate to severe cancer pain were randomly assigned in a double-blind fashion to receive first-dose ketorolac tromethamine 10 mg orally, acetaminophen 600 mg plus codeine 60 mg orally, or placebo, followed by subsequent doses of ketorolac or acetaminophen plus codeine four times daily for 7 days. Patient characteristics were similar among the treatment groups. The first-dose observation documented that both ketorolac and acetaminophen plus codeine produced an equivalent reduction in cancer pain and were superior to placebo as measured by pain intensity differences and pain relief. Multidose comparison documented a small but statistically significant advantage in mean daily pain relief favoring acetaminophen plus codeine, although there were no differences in mean daily ratings of overall effects for either study medication. Adverse symptoms were acceptable with both ketorolac and acetaminophen plus codeine. We conclude that ketorolac has significant analgesic activity in patients with cancer pain, although its precise role in the treatment regimen of these patients remains undefined.

Revascularization of isolated extracorporeal canine eyes by direct microsurgical anastomosis.

Microsurgical techniques were used to anastomose the femoral artery and vein of anesthetized rats to the ciliary artery and internal ophthalmic vein of isolated extracorporeal canine eyes. Microscopic inspection and fluorescein angiography appeared to show early patency of the anastomoses. The application of such an experimental model are discussed.

Comparative studies on synaptosomes: Applicability of the rapid method for preparing synaptosomes to elasmobranch brain.

A flotation technique for the rapid preparation of synaptosomes, originally developed for invertebrate nervous tissue, has now been successfully applied to that of an elasmobranch fish (Mustelis canis, dogfish). The technique involves submitting the supernatant, obtained after a homogenate has been centrifuged at low speed to remove nuclei and tissue debris to centrifugal fields of intermediate intensity (10(6) g/min), appears to separate well-sealed synaptosomes from those less well sealed as judged by the criteria of osmotic shrinkage, enzyme occlusion, and choline uptake. The sealed synaptosomes do not equilibrate with the 0.8 M sucrose used as the homogenization medium and rise to form a coherent pellicle at the top of the tube. Due to the short (1-1/1/2 hr) preparation time, such synaptosomes may well prove useful in further metabolic studies.