Finely controlled size-selective precipitation and separation of CdSe/ZnS semiconductor nanocrystals using CO2-gas-expanded liquids.

A technique was developed to size-selectively separate polydisperse dispersions of CdSe/ZnS nanocrystals into distinct color fractions using only the tunable solvent properties of CO2-expanded hexane. This size-selective precipitation of semiconductor nanoparticles is achieved by finely tuning the solvent strength of the CO2/hexane medium by simply adjusting the applied CO2 pressure. These subtle changes affect the balance between osmotic repulsive and van der Waals attractive forces, thereby allowing fractionation of the nanocrystals into multiple narrow size populations.

The effects of continuing medical education credits on physician response rates to a mailed questionnaire.

This study investigated whether the opportunity to obtain Continuing Medical Education (CME) credit together with a five-dollar bill increased response rates and questionnaire completion rates in a physician survey involving mailed questionnaires. One thousand, three hundred and fourteen cardiologists, family practitioners, general internists (non-surgeons) and 264 vascular surgeons randomly identified from the American Medical Association database participated. After two, of up to four, questionnaire mailings, the opportunity to obtain CME credit and a five-dollar bill were included with questionnaire mailings. Among non-surgeons, 26.5% responded to pre-incentive mailings and 30.2% of those initially unresponsive replied after the interventions. Among surgeons, 39% responded to pre-incentive mailings and 32.7% of those initially unresponsive replied after the interventions. In conclusion, the opportunity to receive CME credit combined with a small monetary incentive is an effective motivation for physicians participating in a study involving mailed questionnaires.

Atherosclerotic risk factor reduction in peripheral arterial diseasea: results of a national physician survey.

OBJECTIVE: Individuals with peripheral arterial disease (PAD) have a 3- to 6-fold increased risk of coronary heart disease and stroke compared to those without PAD. We documented physician-reported practice behavior, knowledge, and attitudes regarding atherosclerotic risk factor reduction in patients with PAD. DESIGN: National physician survey. PATIENTS/PARTICIPANTS: General internists (N = 406), family practitioners (N = 435), cardiologists (N = 473), and vascular surgeons (N = 264) randomly identified using the American Medical Association's physician database. MEASUREMENTS AND MAIN RESULTS: Physicians were randomized to 1 of 3 questionnaires describing a) a 55- to 65-year-old patient with PAD; b) a 55- to 65-year-old patient with coronary artery disease (CAD), or c) a 55- to 65-year-old patient without clinically evident atherosclerosis (no disease). A mailed questionnaire was used to compare physician behavior, knowledge, and attitude regarding risk factor reduction for each patient. Rates of prescribed antiplatelet therapy were significantly lower for the patient with PAD than for the patient with CAD. Average low-density lipoprotein levels at which physicians "almost always" initiated lipid-lowering drugs were 121.6 +/- 23.5 mg/dL, 136.3 +/- 28.9 mg/dL, and 149.7 +/- 24.4 mg/dL for the CAD, PAD, and no-disease patients, respectively (P <.001). Physicians stated that antiplatelet therapy (P <.001) and cholesterol-lowering therapy (P <.001) were extremely important significantly more often for the CAD than for the PAD patient. Perceived importance of risk factor interventions was highly correlated with practice behavior. Compared to other specialties, cardiologists had lowest thresholds, whereas vascular surgeons had the highest thresholds for initiating cholesterol-lowering interventions for the patient with PAD. Cardiologists were significantly more likely to report "almost always" prescribing antiplatelet therapy for the patient with PAD than were all other physicians. CONCLUSIONS: Deficiencies in physician knowledge and attitudes contribute to lower rates of atherosclerotic risk factor reduction for patients with PAD. Reversing these deficiencies may reduce the high rates of cardiovascular morbidity and mortality associated with PAD.

Reduction mammaplasty is a functional operation, improving quality of life in symptomatic women: a prospective, single-center breast reduction outcome study.

Breast hypertrophy creates a functional disability, adversely affecting quality of life because of disproportionate upper body weight. No study to date has prospectively shown or statistically proved (using validated questionnaires) the functional benefits of breast reduction surgery. Moreover, no study has quantified the physical findings seen in these patients. A prospective trial was designed to illustrate objectively the functional benefits of breast reduction surgery and answer the question, Does surgically removing breast tissue in symptomatic patients (regardless of amount of tissue removed) improve their physical disabilities related to breast hypertrophy, and in turn, improve their quality of life? Fifty-five consecutive patients with an average age of 38 years (range, 18 to 73 years) undergoing breast reduction surgery by the senior surgeon (L.A.C.) were recruited for this study. The North American Spine Society (NASS) Lumbar Spine Outcome Assessment Instrument was used to assess patients' disability, expectations for treatment, and satisfaction with treatment. The visual analogue scale was used to quantify pain intensity. Muscle strengths of the pectoralis major, pectoralis minor, rhomboid, middle trapezius, and lower trapezius muscles and postural measures were obtained. Information was collected preoperatively and 6 months postoperatively for comparison. The mean cumulative preoperative NASS Lumbar Spine Outcome Assessment Instrument disability score was 1.94 +/- 0.68, and the mean cumulative postoperative disability score was 1.16 +/- 0.35 (p = 0.0001); 96.1 percent of patients met expectations to a certain degree and, of these patients, 96 percent were very satisfied with their surgery. The mean cumulative baseline preoperative visual analogue score for all participants was 6.2 +/- 2.06, and their mean cumulative postoperative score was 0.53 +/- 0.88 (p = 0.0001). There was statistically significant improvement of muscle strength in the rhomboids, middle trapezius, and lower trapezius muscles (p < 0.001). All postural measures showed improvement postoperatively, with head translation and cranial rotation showing statistical improvement (p < 0.05). This single-center, single-surgeon breast reduction outcome study showed that the signs and symptoms of breast hypertrophy are definable in a consistent manner. By standardizing and quantifying preoperative and postoperative evaluations with validated questionnaires, validated pain scoring, and standardized muscle and posture testing, it was shown that breast reduction for symptomatic breast hypertrophy can effect a statistically significant improvement in these objective measures of pain, disability, muscle weakness, and poor posture.

Assessment of patient-reported clinical outcome in pancreatic and other hepatobiliary cancers: the FACT Hepatobiliary Symptom Index.

This study's aim was to develop and validate a symptom index derived from the Functional Assessment of Cancer Therapy-Hepatobiliary, a questionnaire measuring general and hepatobiliary disease specific aspects of quality of life. The item pool was narrowed to 26 questions that assess symptoms and function. Each of 95 hepatobiliary cancer experts narrowed the list to 5 of the most important to attend to when treating advanced hepatobiliary disease. Eight symptoms were endorsed by more than 20% of the experts (3 pain, 2 fatigue, nausea, weight loss, jaundice) and were named the FACT-Hepatobiliary Symptom Index-8 (FHSI-8). Among 51 hepatobiliary cancer patients, the FHSI-8 showed good internal consistency (0.79), test-retest reliability (r = 0.86), strong association with mood (r = -0.56), and patient differentiation by ECOG Performance Status Rating ( P < 0.0001) and treatment status ( P = 0.057). Symptom scaling in diseases such as hepatobiliary cancer is feasible and may provide an efficient, clinically-relevant endpoint for following groups over time.

Measuring health-related quality of life in patients with hepatobiliary cancers: the functional assessment of cancer therapy-hepatobiliary questionnaire.

PURPOSE: This is the first report on the development and initial validation of the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) questionnaire, a 45-item self-report instrument designed to measure health-related quality of life (HRQL) in patients with hepatobiliary cancers. The FACT-Hep consists of the 27-item FACT-G, which assesses generic HRQL concerns, and the newly validated 18-item Hepatobiliary Subscale (HS), which assesses disease-specific issues. PATIENTS AND METHODS: The development of the HS followed a four-phase process of item generation, item reduction, scale construction, and reliability/validity testing. Two independent samples were studied: item generation (sample 1; n = 30) and reliability/validity testing (sample 2; n = 51). RESULTS: In sample 2, all subscales and aggregated scores showed high internal consistency at initial assessment (Cronbach's alpha range, 0.72 to 0.94) and retesting (Cronbach's alpha range, 0.81 to 0.94). Measurement stability over a 3- to 7-day period was also high for all aggregated scales (test-retest correlation range, 0.84 to 0.91; intraclass correlation coefficient range, 0.82 to 0.90). Convergent and divergent validity were demonstrated by examining relationships between FACT subscales and mood, social support, and social desirability. Finally, when performance status and treatment status were used to divide sample 2, the HS differentiated groups to a degree comparable to the Physical and Functional Well-Being subscales of the FACT-G, thereby contributing favorably to a 32-item Trial Outcome Index. In addition to the 18 validated, scored items in the HS, seven treatment-related items may be appended, if clinically indicated, as a separate subscale. CONCLUSION: The 45-item FACT-Hep can be used independently as a brief measure of disease-related symptoms and functioning. Alone or paired with the FACT-G, the HS has promise for use in assessing the disease-specific HRQL of patients with hepatobiliary cancers.