Transbronchial biopsy in the management of pulmonary complications of hematopoietic stem cell transplantation.

The utility of transbronchial biopsy in the management of pulmonary complications following hematopoietic stem cell transplantation (HSCT) has shown variable results. Herein, we examine the largest case series of patients undergoing transbronchial biopsy following HSCT. We performed a retrospective analysis of 130 transbronchial biopsy cases performed in patients with pulmonary complications post HSCT. Logistic regression models were applied to examine diagnostic yield, odds of therapy change and complications. The most common histologic finding on transbronchial biopsy was a nonspecific interstitial pneumonitis (n=24 cases, 18%). Pathogens identified by transbronchial biopsy were rare, occurring in <5% of cases. A positive transbronchial biopsy significantly increased the odds of a subsequent change in corticosteroid therapy (odds ratio (OR)=3.12; 95% confidence interval (CI) 1.18-8.23; P=0.02) but was not associated with a change in antibiotic therapy (OR=1.01; 95% CI 0.40-2.54; P=0.98) or changes in overall therapy (OR=1.92; 95% CI 0.79-4.70; P=0.15). Patients who underwent a transbronchial biopsy had increased odds of complications related to the bronchoscopy (OR=3.33, 95% CI 1.63-6.79; P=0.001). In conclusion, transbronchial biopsy may contribute to the diagnostic management of noninfectious lung injury post HSCT, whereas its utility in the management of infectious pulmonary complications of HSCT remains low.

Pyrolysis of wastewater biosolids significantly reduces estrogenicity.

Most wastewater treatment processes are not specifically designed to remove micropollutants. Many micropollutants are hydrophobic so they remain in the biosolids and are discharged to the environment through land-application of biosolids. Micropollutants encompass a broad range of organic chemicals, including estrogenic compounds (natural and synthetic) that reside in the environment, a.k.a. environmental estrogens. Public concern over land application of biosolids stemming from the occurrence of micropollutants hampers the value of biosolids which are important to wastewater treatment plants as a valuable by-product. This research evaluated pyrolysis, the partial decomposition of organic material in an oxygen-deprived system under high temperatures, as a biosolids treatment process that could remove estrogenic compounds from solids while producing a less hormonally active biochar for soil amendment. The estrogenicity, measured in estradiol equivalents (EEQ) by the yeast estrogen screen (YES) assay, of pyrolyzed biosolids was compared to primary and anaerobically digested biosolids. The estrogenic responses from primary solids and anaerobically digested solids were not statistically significantly different, but pyrolysis of anaerobically digested solids resulted in a significant reduction in EEQ; increasing pyrolysis temperature from 100°C to 500°C increased the removal of EEQ with greater than 95% removal occurring at or above 400°C. This research demonstrates that biosolids treatment with pyrolysis would substantially decrease (removal>95%) the estrogens associated with this biosolids product. Thus, pyrolysis of biosolids can be used to produce a valuable soil amendment product, biochar, that minimizes discharge of estrogens to the environment.

Do metabolic responses to solar radiation scale directly with intensity of irradiance?

Endotherms exposed to air temperatures below thermal neutrality reduce their metabolic heat production when exposed to sunlight. The physiological effects of this additional source of heat gain from the environment usually are assumed to be proportional to the intensity of irradiance if other factors are held constant. We test this assumption by measuring changes in metabolic heat production produced by exposing a small mammal, the Siberian hamster (Phodopus sungorus) to four intensities of simulated solar radiation (0 W m-2, 317 W m-2, 634 W m-2 and 950 W m-2). In the absence of solar radiation, metabolic heat production is inversely correlated with air temperature over the measured range of 3-27 degrees C. The respiratory quotient varies significantly with ambient temperature, indicating that the catabolic substrate and the thermal equivalent of oxygen consumed or carbon dioxide produced also vary with temperature. The depression of metabolic heat production resulting from exposure to simulated solar radiation is not simply a multiple of the intensity of irradiance. Rather, metabolic responses to higher levels of irradiance are blunted by 14-29% compared with those expected on the basis of the response to less intense irradiance. Because changes in irradiance levels do not have simple linear effects upon the animal's metabolic heat production, even in a simplified situation, significant errors may accumulate in biophysical analyses in which an animal's responses to a restricted set of radiative conditions are measured and the results are extrapolated to a wider range observed in nature.