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Background. Severe pandemic 2009 influenza A virus (H1N1) infection is associated with risk factors that include pregnancy, obesity, and immunosuppression. After identification of immunoglobulin G2 (IgG2) deficiency in 1 severe case, we assessed IgG subclass levels in a cohort of patients with H1N1 infection. Methods. Patient features, including levels of serum IgG and IgG subclasses, were assessed in patients with acute severe H1N1 infection (defined as infection requiring respiratory support in an intensive care unit), patients with moderate H1N1 infection (defined as inpatients not hospitalized in an intensive care unit), and a random sample of healthy pregnant women. Results. Among the 39 patients with H1N1 infection (19 with severe infection, 7 of whom were pregnant; 20 with moderate infection, 2 of whom were pregnant), hypoabuminemia (P < .001), anemia (P < .001), and low levels of total IgG (P = .01), IgG1 (P = .022), and IgG2 (15 of 19 vs 5 of 20; P = .001; mean value ± standard deviation [SD], 1.8 ± 1.7 g/L vs 3.4 ± 1.4 g/L; P = .003) were all statistically significantly associated with severe H1N1 infection, but only hypoalbuminemia (P = .02) and low mean IgG2 levels (P = .043) remained significant after multivariate analysis. Follow-up of 15 (79%) surviving IgG2-deficient patients at a mean (±SD) of 90 ± 23 days (R, 38-126) after the initial acute specimen was obtained found that hypoalbuminemia had resolved in most cases, but 11 (73%) of 15 patients remained IgG2 deficient. Among 17 healthy pregnant control subjects, mildly low IgG1 and/or IgG2 levels were noted in 10, but pregnant patients with H1N1 infection had significantly lower levels of IgG2(P = .001). Conclusions. Severe H1N1 infection is associated with IgG2 deficiency, which appears to persist in a majority of patients. Pregnancy-related reductions in IgG2 level may explain the increased severity of H1N1 infection in some but not all pregnant patients. The role of IgG2 deficiency in the pathogenesis of H1N1 infection requires further investigation, because it may have therapeutic implications. [ABSTRACT FROM AUTHOR]

Paclitaxel is formulated in 50% Cremophor El and 50% ethanol such that patients receiving paclitaxel also receive a significant amount of each of these solvents. The aim of this study was to measure the plasma alcohol levels in patients treated with paclitaxel. A total of 12 patients who were enrolled in phase II trials of non-small-cell lung cancer, breast cancer or ovarian cancer received 175 mg/m2 paclitaxel given as a 3-h infusion. Blood samples were obtained prior to and immediately following the infusion, and plasma ethanol concentrations were measured enzymatically. The dose of ethanol delivered with the paclitaxel ranged from 20.0 to 28.9 ml. No alcohol was detected in pre-dose plasma, but 8 of 12 patients had detectable levels in post-infusion plasma, with 0.033 g/dl being the highest concentration. The elimination rate of alcohol approximates the infusion rate when paclitaxel is given over 3h, resulting in low or undetectable levels in most patients. However, in patients receiving an equivalent dose of paclitaxel given as a 1-h infusion, the plasma alcohol levels will likely be high enough for significant pharmacological effects to occur. [ABSTRACT FROM AUTHOR]

Placental insufficiency can cause fetal growth restriction and stillbirth. There are no reliable screening tests for placental insufficiency, especially near-term gestation when the risk of stillbirth rises. Here we show a strong association between low circulating plasma serine peptidase inhibitor Kunitz type-1 (SPINT1) concentrations at 36 weeks' gestation and low birthweight, an indicator of placental insufficiency. We generate a 4-tier risk model based on SPINT1 concentrations, where the highest risk tier has approximately a 2-5 fold risk of birthing neonates with birthweights under the 3 rd , 5 th , 10 th and 20 th centiles, whereas the lowest risk tier has a 0-0.3 fold risk. Low SPINT1 is associated with antenatal ultrasound and neonatal anthropomorphic indicators of placental insufficiency. We validate the association between low circulating SPINT1 and placental insufficiency in two other cohorts. Low circulating SPINT1 is a marker of placental insufficiency and may identify pregnancies with an elevated risk of stillbirth.

Introduction Dried blood spot (DBS) sample applications now encompass analytes related to clinical diagnosis, epidemiological studies, therapeutic drug monitoring, pharmacokinetic and toxicokinetic studies. Haematocrit (Hct) and haemoglobin (Hb) at very high or low concentrations may influence the accuracy of measurement quantification of the DBS sample. In this study, we aimed to predict the Hct of the punched DBS through primary spectrophotometric estimation of its haemoglobin-derivative (Hb-drv) content. Methods Formic acid solution was used to elute Hb-drv content of 3.2 mm spotted blood from its dry matrix. Direct spectrometry measurement was utilised to scan the extracted Hb-drv in the visible spectrum range of 520-600 nm. The linear relationship between an individual's Hct percentage and Hb-drv concentration was applied to estimate the Hct level of the blood spot. De-identified whole blood samples were used for the method development and evaluation studies. Results The Hb-drv estimation is valid in samples >2 months old. Method validation experiments DBS demonstrate linearity between 82.5 and 207.5 g/L, average coefficient of variation of 3.6% (intra-assay) and 7.7% (inter-assay), analytical recovery of 84%, and a high positive correlation (r=0.88) between Hb-drv and the original whole blood Hct. The Bland-Altman difference plot demonstrates a mean difference of 2.4% between the calculated DBS Hct and the directly measured Hct from fresh whole bloods. Conclusions We have successfully developed a simple Hb-drv method to estimate Hct in aged DBS samples. This method can be incorporated into DBS analytical work-flow for the in-situ estimation of Hct and subsequent correction of the analyte of interest as required.

Objective: To use admission inpatient glycated hemoglobin (HbA1c) testing to help investigate the prevalence of unrecognized diabetes, the cumulative prevalence of unrecognized and known diabetes, and the prevalence of poor glycemic control in both. Moreover, we aimed to determine the 6-month outcomes for these patients. Finally, we aimed to assess the independent association of diabetes with these outcomes., Research Design and Methods: Prospective observational cohort study conducted in a tertiary hospital in Melbourne, Australia., Patients: A cohort of 5082 inpatients ≥54 years admitted between July 2013 and January 2014 underwent HbA1c measurement. A previous diagnosis of diabetes was obtained from the hospital medical record. Patient follow-up was extended to 6 months., Results: The prevalence of diabetes (known and unrecognized) was 34%. In particular, we identified that unrecognized but HbA1c-confirmed diabetes in 271 (5%, 95% CI 4.7% to 6.0%) patients, previously known diabetes in 1452 (29%, 95% CI 27.3% to 29.8%) patients; no diabetes in 3359 (66%, 95% CI 64.8-67.4%) patients. Overall 17% (95% CI 15.3% to 18.9%) of patients with an HbA1c of >6.5% had an HbA1c ≥8.5%. After adjusting for age, gender, Charlson Index score, estimated glomerular filtration rate, and hemoglobin levels, with admission unit treated as a random effect, patients with previously known diabetes had lower 6-month mortality (OR 0.69, 95% CI 0.56 to 0.87, p=0.001). However, there were no significant differences in proportions of intensive care unit admission, mechanical ventilation or readmission within 6 months between the 3 groups., Conclusions: Approximately one-third of all inpatients ≥54 years of age admitted to hospital have diabetes of which about 1 in 6 was previously unrecognized. Moreover, poor glycemic control was common. Proportions of intensive care unit admission, mechanical ventilation, or readmission were similar between the groups. Finally, diabetes was independently associated with lower 6-month mortality.

Background: Trimester-specific reference intervals (RIs) for thyroid function tests are lacking for Beckman Dxl 800 analysers. We aimed to establish RIs for thyroid stimulating hormone (TSH), free thyroxine (fT4) and to track intraindividual changes in thyroid function throughout pregnancy., Methods: One hundred and thirty healthy women without antithyroid peroxidase antibodies were followed longitudinally. Thyroid function was determined at trimester-1 (T1): 9-13 weeks; trimester-2 (T2): 22-26 weeks; trimester-3 (T3): 35-39 weeks and postpartum (PP): 8-12 weeks. A subgroup (n = 47) was used to track intraindividual changes using PP as non-pregnant state (baseline)., Results: For trimesters 1-3, TSH (median (2.5th, 5th, 95th and 97.5th percentile)) was 0.77 (0.03, 0.05, 2.33, 3.05), 1.17 (0.42, 0.47, 2.71, 3.36) and 1.35 (0.34, 0.42, 2.65, 2.83) mIU/L, respectively. Free T4 (mean (95%CI)) was 10.7 (5.9-15.5), 8.1 (4.9-11.3), 7.8 (4.5-11.0) pmol/L, respectively. In T2 and T3, 36% and 41% of the fT4 values, respectively, fell below the non-pregnancy lower normal limit. In the subgroup assessed for longitudinal changes, of the women with baseline TSH ≤ median, 71-75% remained at or below the corresponding median for trimesters 1-3. Of the women with baseline fT4 ≤ median, 69-81% also remained at or below the corresponding median for trimesters 1-3. High correlation was observed at different trimesters and baseline for TSH (Spearman's r: 0.593-0.846, P < 0.001) and for fT4 (r: 0.480-0.739, P < 0.001)., Conclusions: Use of trimester-specific RIs would prevent misclassification of thyroid function during pregnancy. In the majority of women, TSH and fT4 tracked on the same side of the median distribution, from a non-pregnant baseline, throughout pregnancy.

Cremophor EL, a surfactant used in the clinical formulation of cyclosporine and paclitaxel, will reverse the multidrug resistance (MDR) phenotype in vitro. As other MDR modulators can alter the pharmacokinetics of cytotoxic drugs, the aim of this study was to examine the effect of Cremophor and another MDR-reversing surfactant, Tween 80, on the hepatic elimination and biliary excretion of etoposide. Using the isolated perfused rat-liver model with 80 ml recirculating perfusate containing 20% red blood cells and 4% bovine serum albumin, etoposide (1.6 mg) with and without Cremophor (800 or 80 mg) or Tween 80 (80 mg) was given into the perfusate reservoir, and perfusate and bile samples were collected for 3 h. Etoposide was measured by high-performance liquid chromatography (HPLC) and Cremophor was measured using a bioassay. Both surfactants changed the etoposide elimination profile from biphasic to monophasic. High-dose Cremophor increased the AUC (from 334 +/- 23 to 1540 +/- 490 microgram min ml(-1), P<0.05) and decreased the total clearance (from 4.8 +/- 0.3 to 1.1 +/- 0.3 ml/min, P<0.05) and biliary clearance (from 2.6 +/- 1.1 to 0.5 +/- 0.2 ml/min, p<0.05) but decreased the elimination half-life (from 62 +/- 17 to 40 +/- 5 min, P<0.05) and volume of distribution (from 424 +/- 85 to 65 +/- 19 ml, P<0.05). Low-dose Cremophor and Tween 80 caused intermediate effects on these parameters that were statistically significant for total clearance, half-life, and volume of distribution. Cremophor had no adverse effect on liver function, whereas Tween 80 caused haemolysis and cholestasis. The initial high-dose Cremophor perfusate concentration was 0.8 mg/ml, which previous studies have shown to be clinically relevant and close to the optimal level for MDR reversal in vitro (1.0 mg/ml). Cremophor may be a clinically useful MDR modulator, but it may alter the pharmacokinetics of the cytotoxic drug.

A high-performance liquid chromatographic method has been developed for the measurement of toremifene and its major human metabolites in plasma and urine. We have simplified other published methods, such that our assay uses protein precipitation in place of organic extraction, and ultraviolet detection instead of photochemical activation followed by fluorescence detection. In a stability study toremifene and metabolites remained unchanged for up to seven weeks at -70 degrees C. This simple and specific assay allowed toremifene and three metabolites to be quantitated for pharmacokinetic analyses in a high-dose Phase I trial.

Because it is thought that chloramphenicol is poorly absorbed after intramuscular administration, we compared blood levels of chloramphenicol after intramuscular administration with those after intravenous administration in children with a variety of diagnoses. Fifty-seven children were studied on 62 occasions while they were receiving chloramphenicol sodium succinate (25 mg of chloramphenicol per kilogram of body weight) intramuscularly every six hours. The peak level of chloramphenicol was 19.5 +/- 5.99 micrograms per milliliter (mean +/- S.D.) in 11 children after the first dose and 31.4 +/- 12.99 micrograms per milliliter in 51 children after two or more doses. The lowest peak level after intramuscular administration was 13 micrograms per milliliter, which is in the therapeutic range of 10 to 30 micrograms per milliliter. Thirteen children were studied on 17 occasions while they were receiving chloramphenicol sodium succinate (25 mg of chloramphenicol per kilogram) intravenously every six hours. The peak level of chloramphenicol was 19.4 +/- 6.37 micrograms per milliliter in eight children after the first dose and 28.2 +/- 11.09 micrograms per milliliter in nine children after two or more doses. The area under the serum level curve was not significantly different after intramuscular and intravenous administration. We conclude that chloramphenicol sodium succinate is well absorbed after intramuscular administration. This route is cheaper, it demands less staff time, and it does not carry the risks of sepsis and overhydration associated with intravenous therapy.