Wide-band fiber optic signal processor

Operation of a 16-tap fiber-optic delay line configured as a bandpass filter with a fundamental frequency of 2.0 GHz over the frequency range from 0 to 12.5 GHz is discussed. Equal tap weights and spacings were used to facilitate comparison of experimental and predicted results. More than 10¹¹ analog multiplications per second are performed in this relatively simple signal processing system. Other processors for performing functions such as matched filtering and correlation can be implemented by appropriate choice of the mirror reflectances and fiber lengths     

Phase II trial of paclitaxel and granulocyte colony-stimulating factor in patients with pancreatic carcinoma: a Southwest Oncology Group study

PURPOSE: Pancreatic cancer is difficult to treat, with most patients surgically unresectable at the time of diagnosis. Radiotherapy and chemotherapy can offer palliation, but more effective therapy is needed. This trial evaluated the effects of an aggressive schedule of paclitaxel given with granulocyte colony-stimulating factor (G-CSF) to patients with advanced pancreatic cancer. PATIENTS AND METHODS: All patients were required to have a histologic diagnosis of pancreatic adenocarcinoma with measurable disease and no prior chemotherapy or radiation therapy. Patients had to have performance status of 0 to 2, pretreatment absolute granulocyte count > or = 1,500/microL, and platelet count greater than or equal to the institutional lower limit of normal. Following pretreatment with dexamethasone, diphenhydramine, and cimetidine, patients received paclitaxel at a dose of 250 mg/m2 by 24-hour infusion on day 1, repeated every 21 days. G-CSF was given at a dose of 5 microg/kg/d on days 3 to 18 or until two consecutive absolute neutrophil counts (ANCs) > or = 10,000/microL were obtained. Doses of paclitaxel were modified depending on nadir counts. RESULTS: Forty-five patients were entered onto this study, with six ineligible. For the 39 eligible patients, there was one complete response (CR) and two partial responses (PRs), five stable/no responses, 23 increasing disease, two early deaths, and six patients whose assessment was inadequate to determine response. The response rate was therefore three of 39 or 8% (95% confidence interval [CI], 2% to 21%). The median survival time for the 39 eligible patients was 5 months. The most common toxicities were anemia, leukopenia/granulocytopenia, malaise/fatigue, nausea/vomiting, alopecia, thrombocytopenia, paresthesias, and liver function abnormalities. There was one death due to sepsis. CONCLUSION: Single-agent paclitaxel in this dose and schedule has minimal activity in pancreatic adenocarcinoma patients.     

Influence of regular aerobic exercise on psychological health: A randomized, controlled trial of healthy middle-aged adults.

Evaluated 120 healthy, sedentary, middle-aged adults randomly assigned to either a 6-mo home-based aerobic exercise training program or to an assessment-only control condition. Adherence across the 6-mo period by the exercise group was demonstrated by self-report and heart rate microprocessor methods to exceed 75%. A 14-item Likert rating scale was used to measure a variety of psychological variables. Significant between-groups differences favoring the exercise group were found on scale items closely associated with actual physical changes that occurred with exercise (satisfaction with shape/appearance, perceived fitness). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sub-100 fs Kerr lens modelocked Cr4+:YAG laser

Sub-100 fs pulse generation from a Kerr lens modelocked Cr⁴⁺ :YAG laser has been demonstrated for the first time, yielding femtosecond pulses tunable from 1.49 to 1.56 μm with pulses as short as 90 fs obtained at 1.53 μm     

Terson''s syndrome in a patient with acute promyelocytic leukemia on all-trans retinoic acid treatment

Hypothermia induced by surface cooling has shown to protect vulnerable regions of the brain during an ischemic insult. This study evaluated the neuroprotective efficacy of neurotensin, a potent hypothermic agent, using a 5-min carotid occlusion procedure in the gerbil. In Experiment 1, the dose-response and time course of neurotensin-induced hypothermia were evaluated (n = 5/dose). Central infusion of 10, 20, and 30 micrograms neurotensin were found to significantly decrease core body temperature of conscious gerbils within 30 min of administration. In Experiment 2, gerbils pretreated with 30 micrograms neurotensin were permitted to become hypothermic or were maintained at 37 degrees-38 degrees C (rectal) during ischemic insult. Other gerbils were pretreated with peptide vehicle prior to ischemic insult (at 37 degrees -38 degrees C) or underwent a sham procedure (n = 6/condition). At 24 h after surgery, gerbils were tested for increased locomotor activity in an open-field apparatus. Gerbils pretreated with peptide vehicle or neurotensin and maintained at 37 degrees-38 degrees C during ischemia had significantly higher activity levels compared to the other treated groups. In contrast, gerbils made hypothermic with neurotensin exhibited activity levels similar to sham gerbils. Histological assessment revealed that neurotensin-induced hypothermia protected the CA1 region from ischemic damage.     

Methotrexate in the management of severe steroid dependent asthma

AIMS: This study was designed to assess the efficacy of low dose methotrexate, 15 mg weekly, as a steroid-sparing agent in asthmatic patients requiring long-term oral prednisone treatment. METHODS: The study was a randomised, double blind, placebo controlled, cross over study of 48 weeks duration. Eleven patients with severe steroid-dependent asthma were included. A successful outcome was defined as a reduction in mean prednisone requirements of 7 mg daily compared to baseline requirements, during active treatment. RESULTS: Two patients were required to be withdrawn owing to methotrexate-related adverse effects. The mean prednisone dose for patients who completed the study was 14.4 mg per day (95% CI; 13.6, 15.1) during active treatment, and 12.9 mg per day (95% CI: 12.2, 13.6) during placebo treatment (NS). Only one patient reduced his individual dose requirements by more than 7 mg per day, whereas in three patients prednisone requirements actually increased during active treatment. There were no significant differences in symptom scores, pulmonary function data, and exacerbations between active and placebo treatments. CONCLUSION: No significant steroid-sparing effect was obtained using low dose methotrexate in this study. This negative outcome may be attributable to the small population of patients studied, low baseline FEV1, and the omission of a steroid minimisation run-in period. Our results highlight the importance of careful patient selection and a painstaking approach in the management of patients with steroid-dependent asthma.     

Ultrastructural studies of spermiogenesis in rabbit exposed to chronic fluoride toxicity

OBJECTIVE: To compare skinfold thickness measurements with bioelectrical impedance analysis (BIA) as a measure of body fat for use in a survey of children (the National Study of Health and Growth). DESIGN: Part cross-sectional, part repeated measurement study. SETTING: A junior school in Bath. SUBJECTS: 42 boys and 33 girls aged from 9 to 11 years. INTERVENTIONS: Measurements of BIA, height, weight, and triceps, biceps, subscapular and suprailiac skinfolds. RESULTS: All measurements were highly repeatable with intraclass correlation coefficients > 0.90. The level of agreement between estimates of percentage of body fat derived from prediction equations based on impedance or skinfold measurements respectively was poor: the mean difference (impedance estimate minus skinfold estimate) was 4.67% (95% range -3.47 to 12.82) for boys and 7.81% (95% range 1.27 to 14.34) for girls. The two estimates were found to correlate highly (r = 0.83 for boys and r = 0.81 for girls) because weight, used to convert estimates of fat-free mass derived from impedance to fat mass, was highly correlated with impedance and moderately highly correlated with skinfold thicknesses. The correlations of resistance (R) and (H)2/R with skinfold thicknesses were very low. There was a moderate correlation of R and H2/R with log(weight-for-height index), but lower than that of log(weight-for-height index) with each of the skinfolds. CONCLUSIONS: As currently available equations for converting impedance-based estimates of total body water to fat mass are not fully developed for use in children of varying ages, estimates of body fat calculated from skinfold thickness measurements remain preferable in epidemiological studies of children's health and growth.