Two-dimensional structured illumination microscopy.

In widefield fluorescence microscopy, images from all but very flat samples suffer from fluorescence emission from layers above or below the focal plane of the objective lens. Structured illumination microscopy provides an elegant approach to eliminate this unwanted image contribution. To this end a line grid is projected onto the sample and phase images are taken at different positions of the line grid. Using suitable algorithms 'quasi-confocal images' can be derived from a given number of such phase-images. Here, we present an alternative structured illumination microscopy approach, which employs two-dimensional patterns instead of a one-dimensional one. While in one-dimensional structured illumination microscopy the patterns are shifted orthogonally to the pattern orientation, in our two-dimensional approach it is shifted at a single, pattern-dependent angle, yet it already achieves an isotropic power spectral density with this unidirectional shift, which otherwise would require a combination of pattern-shift and -rotation. Moreover, our two-dimensional approach also yields a better signal-to-noise ratio in the evaluated image.

N-acetylcysteine reduces malondialdehyde levels in chronic hemodialysis patients--a pilot study.

BACKGROUND: Oxidative stress has been implicated in the development of endothelial damage in hemodialysis (HD). We have assessed the effects of N-acetylcysteine (NAC), a compound with antioxidant effects, on malondialdehyde (MDA), a marker of oxidative stress on lipid peroxidation. METHODS: A clinical trial was conducted in which 24 chronic HD patients were divided into 2 groups according to gender, age, time on HD and cause of renal failure. The NAC group (n = 12) received 600 mg of NAC twice a day for 30 days. The remaining patients constituted the control group (n = 12). MDA levels were measured pre- and post-dialysis at the beginning of the study (baseline) and on day 30 (30 days). RESULTS: Baseline pre- and post-dialysis MDA levels were not different between both groups and were above normal values. A significant decrease was found in the NAC group when either pre- or post-dialysis MDA levels were compared to the corresponding control group levels on day 30 (pre-dialysis NAC vs control group 3.01 +/- 0.6 vs 4.5 +/- 0.73 micromol/l, p < 0.0001, post-dialysis NAC vs control group 2.76 +/- 0.5 vs 4.39 +/- 0.7 micromol/l, p < 0.0001). Only in the NAC group were pre-dialysis MDA 30-day levels different from pre-dialysis baseline levels (3.01 +/- 0.6 vs 5.07 +/- 1.6 micromol/l, p < 0.002). Post-dialysis MDA 30-day concentrations were significantly lower than post-dialysis MDA baseline levels (2.76 +/- 0.5 vs 4.32 +/- 0.7 micromol/l, p < 0.002) and pre-dialysis MDA 30-day measurements (2.76 +/- 0.5 vs 3.01 +/- 0.6 micromol/l, p < 0.011). CONCLUSIONS: MDA levels are elevated in chronic HD patients and are not significantly reduced by HD. NAC significantly reduces malondialdehyde levels in chronic HD patients.

Derivation and validation of a methodology for tracking academic stature of medical schools. Task Force on the Development of Emergency Medicine.

OBJECTIVE: To derive and validate a methodology for academic ranking of allopathic medical schools in order to track the development of emergency medicine (EM) at academic medical centers. METHODS: A methodology for institutional ranking according to NIH research grant funding was derived by using a well-known multiaxial ordinal ranking of all Liaison Committee on Medical Education (LCME)-accredited allopathic schools in 1990-91 as the criterion standard. This methodology was validated against the same annually updated criterion standard in 1995-96. Both ranking schemes were first stratified by quartile, then aggregated pairwise by contiguous quartiles to develop a 3 x 3 concordance matrix. RESULTS: Ranking by NIH grant funding produced concordance between all 126 schools in the derivation set and 123/124 schools in the validation set. CONCLUSION: NIH research grant funding may be used as a valid methodology for broad categorization of allopathic medical school academic rank. This strategy should therefore serve as a suitable means of following the development of academic EM over time.

Changing status of academic emergency medicine (1991-1996). Task Force on the Development Emergency Medicine.

OBJECTIVE: An SAEM national task force previously concluded that academic departments and residencies in emergency medicine (EM) had preferentially developed outside of the academic mainstream. This study was designed to determine whether EM has made significant inroads into academic medical centers over the past 5 years. METHODS: The baseline data set (7/1/91) contained all 126 Liaison Committee on Medical Education (LCME)-accredited schools, and all 87 Residency Review Committee (RRC)-accredited EM residencies. The comparison data set (7/1/96) contained all 124 LCME-accredited schools, and all 114 RRC-accredited EM residencies. The 1991-96 increments in academic departments and university-hospital residencies was examined in the aggregate, then stratified by medical schools grouped into quartiles and contiguous quartiles, according to academic ranking. A-priori and post-hoc comparisons were expressed with 95% and 99% confidence intervals (CIs), respectively. RESULTS: Over the past 5 years, the proportion of academic departments of EM increased by 23%, from 18% to 41% of all LCME-accredited schools (95% CI 12% to 34%). The largest increase (58%; 99% CI 40% to 77%) occurred among those schools academically ranked above the median. The proportion of EM residencies at university hospitals increased by 17%, from 40% to 57% (95% CI 5% to 30%). Again, the largest increase (25%; 99% CI 3% to 47%) occurred at university hospitals affiliated with schools academically ranked above the median. CONCLUSION: EM has made substantial inroads into academic medical centers over the past 5 years. This is reflected in quantitatively and statistically significant increases in academic departments and university-hospital residency programs, both occurring largely within institutions whose academic rankings place them among the upper half of all LCME-accredited medical schools.

Geriatric training in emergency medicine residency programs.

STUDY OBJECTIVES: The health care needs of the elderly population are significantly different from those of younger patients and require special knowledge and skills on the part of emergency physicians. The purpose of this study was to identify the nature and extent of geriatric training currently provided to emergency medicine residents. DESIGN: Self-administered survey distributed to residency directors of the 85 accredited emergency medicine residency programs in the United States. INTERVENTIONS: The survey consisted of 17 questions focusing on residency directors' views about teaching and research of geriatric emergency care. RESULTS: Survey information was obtained from 85 (100%) emergency medicine residency programs. Forty percent (34 of 85) of respondents believed the teaching of geriatric emergency care was inadequate; 44 programs (52%) plan to increase the number of didactic hours devoted to geriatrics (mean increase of 5.9 hours). The five geriatric topics most frequently taught included acute dementia, atypical presentation of illness, common complaints in the elderly, geriatric trauma, and ethical issues. Sixty-five percent believed ongoing national research efforts regarding geriatric emergency medicine were insufficient; 21 programs (25%) had faculty involved in geriatric studies. Most respondents reported that growing numbers of elderly will have a major impact on all areas of patient care in the near future. CONCLUSION: Although geriatric emergency care is becoming an integral part of the emergency medicine residency program, there may be a need for better focused and more intensive training.