J

Jim Young

University of Iowa

ORCID: 0000-0002-4314-3007

Publishes on Health and Medical Studies, Medical and Health Sciences Research, HIV-related health complications and treatments. 384 papers and 5.8k citations.

384Publications
5.8kTotal Citations

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Sirolimus and Kidney Growth in Autosomal Dominant Polycystic Kidney Disease
Andreas L. Serra, Diane Poster, Andreas D. Kistler et al.|New England Journal of Medicine|2010
Cited by 559Open Access

In autosomal dominant polycystic kidney disease (ADPKD), aberrant activation of the mammalian target of rapamycin (mTOR) pathway is associated with progressive kidney enlargement. The drug sirolimus suppresses mTOR signaling.In this 18-month, open-label, randomized, controlled trial, we sought to determine whether sirolimus halts the growth in kidney volume among patients with ADPKD. We randomly assigned 100 patients between the ages of 18 and 40 years to receive either sirolimus (target dose, 2 mg daily) or standard care. All patients had an estimated creatinine clearance of at least 70 ml per minute. Serial magnetic resonance imaging was performed to measure the volume of polycystic kidneys. The primary outcome was total kidney volume at 18 months on blinded assessment. Secondary outcomes were the glomerular filtration rate and urinary albumin excretion rate at 18 months.At randomization, the median total kidney volume was 907 cm3 (interquartile range, 577 to 1330) in the sirolimus group and 1003 cm3 (interquartile range, 574 to 1422) in the control group. The median increase over the 18-month period was 99 cm3 (interquartile range, 43 to 173) in the sirolimus group and 97 cm3 (interquartile range, 37 to 181) in the control group. At 18 months, the median total kidney volume in the sirolimus group was 102% of that in the control group (95% confidence interval, 99 to 105; P=0.26). The glomerular filtration rate did not differ significantly between the two groups; however, the urinary albumin excretion rate was higher in the sirolimus group.In adults with ADPKD and early chronic kidney disease, 18 months of treatment with sirolimus did not halt polycystic kidney growth. (Funded by Wyeth and others; ClinicalTrials.gov number, NCT00346918.)

Procalcitonin-Guided Antibiotic Use vs a Standard Approach for Acute Respiratory Tract Infections in Primary Care
Matthias Briel, Philipp Schüetz, Beat Müeller et al.|Archives of Internal Medicine|2008
Cited by 320

BACKGROUND: Acute respiratory tract infections are the most common reason for antibiotic therapy in primary care despite their mainly viral etiology. A laboratory test measuring procalcitonin levels in blood specimens was suggested as a tool to reduce unnecessary prescribing of antibiotics. We consider whether antibiotic therapy guided by procalcitonin reduces the use of antibiotics without increasing the restrictions experienced by patients by more than 1 day. METHODS: Fifty-three primary care physicians recruited 458 patients, each patient with an acute respiratory tract infection and, in the physician's opinion, in need of antibiotics. Patients were centrally randomized to either a procalcitonin-guided approach to antibiotic therapy or to a standard approach. For patients randomized to procalcitonin-guided therapy, the use of antibiotics was more or less strongly discouraged (procalcitonin level, < or =0.1 or < or =0.25 microg/L, respectively) or recommended (procalcitonin level, >0.25 microg/L). Follow-up data were collected at 7 days by treating physicians and at 14 and 28 days by blinded interviewers. RESULTS: Adjusted for baseline characteristics, the mean increase at 14 days in days in which activities were restricted was 0.14 with procalcitonin-guided therapy (95% confidence interval [CI], -0.53 to 0.81 days), which met our criterion of an increase in days in which activities were restricted by no more than 1 day. With procalcitonin-guided therapy, the antibiotic prescription rate was 72% lower (95% CI, 66%-78%) than with standard therapy. Both approaches led to a similar proportion of patients reporting symptoms of ongoing or relapsing infection at 28 days (adjusted odds ratio, 1.0 [95% CI, 0.7-1.5]). CONCLUSIONS: As an adjunct to guidelines, procalcitonin-guided therapy markedly reduces antibiotic use for acute respiratory tract infections in primary care without compromising patient outcome. In practice, this could be achieved with 1 to 2 procalcitonin measurements in patients for whom the physician intends to prescribe antibiotics.

Fourier Transform Infrared Spectroscopy of Aerosol Collected in a Low Pressure Impactor (LPI/FTIR): Method Development and Field Calibration
David T. Allen, Edward Palen, Mitchell I. Haimov et al.|Aerosol Science and Technology|1994
Cited by 154

A method for determining the loadings of organic and inorganic functional groups in size segregated ambient aerosol has been developed and demonstrated. The method uses a Hering Low Pressure Impactor (LPI), equipped with ZnSe impaction surfaces, to sample the aerosol. The aerosol samples are analyzed directly, without extraction, using transmission infrared spectroscopy. The resulting spectra of aerosol size fractions are used to determine loadings of sulfate ion, nitrate ion, aliphatic carbon, carbonyl and organonitrate groups, using calibration factors developed in field and model compound studies. This paper describes, in detail, the data interpretation and calibration methods used to obtain these functional group loadings from the infrared spectra. The functional group loadings, particularly the size distributions of organic compound classes, provide new insights into the composition of atmospheric aerosol.