Long-term mortality of hospitalized pneumonia in the EPIC-Norfolk cohort.

Little is known about cause-specific long-term mortality beyond 30 days in pneumonia. We aimed to compare the mortality of patients with hospitalized pneumonia compared to age- and sex-matched controls beyond 30 days. Participants were drawn from the European Prospective Investigation into Cancer (EPIC)-Norfolk prospective population study. Hospitalized pneumonia cases were identified from record linkage (ICD-10: J12-J18). For this study we excluded people with hospitalized pneumonia who died within 30 days. Each case identified was matched to four controls and followed up until the end June 2012 (total 15 074 person-years, mean 6·1 years, range 0·08-15·2 years). Cox regression models were constructed to examine the all-cause, respiratory and cardiovascular mortality using date of pneumonia onset as baseline with binary pneumonia status as exposure. A total of 2465 men and women (503 cases, 1962 controls) [mean age (s.d.) 64·5 (8·3) years] were included in the study. Between a 30-day to 1-year period, hazard ratios (HRs) of all-cause and cardiovascular mortality were 7·3 [95% confidence interval (CI) 5·4-9·9] and 5·9 (95% CI 3·5-9·7), respectively (with very few respiratory deaths within the same period) in cases compared to controls after adjusting for age, sex, asthma, smoking status, pack years, systolic and diastolic blood pressure, diabetes, physical activity, waist-to-hip ratio, prevalent cardiovascular and respiratory diseases. All outcomes assessed also showed increased risk of death in cases compared to controls after 1 year; respiratory cause of death being the most significant during that period (HR 16·4, 95% CI 8·9-30·1). Hospitalized pneumonia was associated with increased all-cause and specific-cause mortality beyond 30 days.

Effect of exercise on the diurnal variation in energy substrate use during a high-fat diet.

Aerobic exercise increases 24-h fat oxidation following initiation of a high-fat diet. The objective of this study is to examine the time course of increased fat oxidation under exercise and sedentary conditions. Eighteen healthy subjects completed a randomized crossover design (sedentary and exercise visits) staying for five consecutive days in a metabolic chamber each visit. On day 1, 30% of energy intake was from fat; days 2-5 had 50% of energy as fat. During exercise, subjects rode on a stationary cycle at 45% of VO2max for 1 h in the mornings and evenings. Respiratory gases and urinary nitrogen were collected to calculate macronutrient oxidation and non-protein respiratory exchange ratio (NPRER). This data, collected continuously (24-h periods), were subsequently divided into three time segments: (1) exercise + recovery (1000-1200 hours, 2100-2200 hours), (2) sleep (2300-0645 hours), and (3) wake (all remaining hours). NPRER on exercise versus sedentary visits was lower for the sleep segment (0.77 ± 0.01 01 vs. 0.81 ± 0.01, p < 0.001), higher for the exercise + recovery segment (0.88 ± 0.01 vs. 0.86 ± 0.01, p < 0.001), and was not different for the wake segment. Fat oxidation was significantly higher for exercise versus sedentary treatments during sleep (41 ± 2 vs. 31 ± 2 g), wake (62 ± 3 vs. 51 ± 3 g), and exercise + recovery segments (33 ± 3 vs.16 ± 1 g), but so was fat intake by design (171 ± 8 vs. 128 ± 7 g/d). Although exercise showed greater fat oxidation during all segments, dietary fat intake was also higher. Therefore, based on NPRER, the time of day during which the exercise treatment increased the ratio of fat to carbohydrate oxidation was during sleep.

A rapid diffusion immunoassay in a T-sensor.

We have developed a rapid diffusion immunoassay that allows measurement of small molecules down to subnanomolar concentrations in <1 min. This competitive assay is based on measuring the distribution of a labeled probe molecule after it diffuses for a short time from one region into another region containing antigen-specific antibodies. The assay was demonstrated in the T-sensor, a simple microfluidic device that places two fluid streams in contact and allows interdiffusion of their components. The model analyte was phenytoin, a typical small drug molecule. Clinically relevant levels were measured in blood diluted from 10- to 400-fold in buffer containing the labeled antigen. Removal of cells from blood samples was not necessary. This assay compared favorably with fluorescence polarization immunoassay (FPIA) measurements. Numerical simulations agree well with experimental results and provide insight for predicting assay performance and limitations. The assay is homogeneous, requires <1 microl of reagents and sample, and is applicable to a wide range of analytes.

Analysis of chlortetracycline by high performance liquid chromatography with postcolumn alkaline-induced fluorescence detection.

A high performance liquid chromatographic method for the analysis of chlortetracycline (CTC) using postcolumn fluorescence detection has been developed. After chromatographic separation of CTC on a polystyrene-divinylbenzene copolymer column, a highly fluorescent derivative isochlortetracycline (iso-CTC) was formed postcolumn in an on-line reaction coil with the addition of 25% NaOH (w/v). Chromatographic separation was achieved on a PRP-1 column, 15 cm x 4.6 mm, with 27:73 acetonitrile:0.2% perchloric acid (v/v), at 1.0 mL/min. Fluorescence derivatization was achieved by the on-line addition of 25% NaOH (w/v), at a flow rate of 0.2 mL/min, into the column eluant in a post-column reaction coil. The reaction coil was 9 m of teflon (1/16 in o.d., 0.3 mm i.d.) knitted into a six-sided coil. The fluorescent derivative was detected at lambda ex 355 nm and lambda em > 389 nm. Using this method after a simple sample cleanup, CTC can be detected in milk at 0.04 micrograms/mL, which is comparable to that obtained by microbiological assays. The detection method was linear between 0.02 micrograms/mL and 4 micrograms/mL. Because of the chromatographic separation, the method is more selective than microbiological assays and more sensitive than ultraviolet detection. With the chromatographic system described, the keto tautomeric forms of CTC and 4-epi-CTC are separated in a system which minimizes their formation on-column. In acidic aqueous organic solutions, the keto tautomer of CTC is the only product formed to any significant amount.