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Objective: To review the clinical presentation, radiology, microbiology, and response to therapy of patients with chronic bacterial pneumonia. Design: A retrospective analysis. Setting: An urban tertiary care medical center. Participants: One hundred fifteen patients with pulmonary and/or constitutional symptoms of at least 1 month's duration with 4,000 or more colony-forming units (CFUs) of a single bacterial species identified by quantitative culture obtained via fiberoptic bronchoscopy. Measurements: Charts were analyzed for presence or absence of any predisposing illness, symptoms at presentation, roentgenographic abnormalities, microbiologic results, findings at fiberoptic bronchoscopy, and results of therapeutic intervention. Results: Sixty-five percent of patients with chronic bacterial pneumonia had a predisposing disease, 35 percent were “normal.” Cough, fatigue, dyspnea, and weight loss were predominant symptoms in both groups. Bronchogenic carcinoma was newly diagnosed in 16 patients (14 percent). Haemophilus influenzae or alpha-hemolytic streptococcus was isolated in 68 percent of patients. Risk of recurrence of infection was inversely associated with duration of therapy in both groups. Conclusions: Chronic bacterial pneumonia is more common than previously recognized. It occurs in patients with and without a predisposing illness. Clinical presentation, roentgenographic appearance, and bacteriology are similar between the two groups. Cure requires prolonged antibiotic therapy.

Bioremediation is an important approach to waste reduction that relies on biological processes to break down a variety of pollutants. This is made possible by the vast metabolic diversity of the microbial world. To explore this diversity for the breakdown of plastic, we screened several dozen endophytic fungi for their ability to degrade the synthetic polymer polyester polyurethane (PUR). Several organisms demonstrated the ability to efficiently degrade PUR in both solid and liquid suspensions. Particularly robust activity was observed among several isolates in the genus Pestalotiopsis , although it was not a universal feature of this genus. Two Pestalotiopsis microspora isolates were uniquely able to grow on PUR as the sole carbon source under both aerobic and anaerobic conditions. Molecular characterization of this activity suggests that a serine hydrolase is responsible for degradation of PUR. The broad distribution of activity observed and the unprecedented case of anaerobic growth using PUR as the sole carbon source suggest that endophytes are a promising source of biodiversity from which to screen for metabolic properties useful for bioremediation.

BACKGROUND AND PURPOSE: Ketone bodies provide important alternate fuel for brain metabolism, and their transport into the brain increases with prolonged fasting. During diabetic ketoacidosis (DKA), serum ketone concentrations markedly increase; however, little is known about whether ketone bodies accumulate in cerebral tissues during DKA. We used proton MR spectroscopy (MRS) to detect cerebral β-hydroxy butyrate (βOHB) and acetone/acetocaetate (AcAc) in children with DKA. METHODS: Twenty-five children underwent brain MRS: nine within 4 hours of the start of treatment for DKA; 11, at 4–8 hours; and five, at 8–12 hours. MRS was repeated after their recovery from the DKA episode at ≥72 hours after the start of treatment. MRS was evaluated for peaks corresponding to βOHB (doublet centered on 1.20 ppm) and lactate (doublet centered on 1.33 ppm). Difference spectroscopy was used to identify the AcAc peak at 2.22–2.26 ppm. RESULTS: βOHB was detected in 13 children (52%), more frequently within 4 hours (eight children, 89%) than after 4 hours (five children, 31%). AcAc was detected in 15 children (60%), more frequently at >4 hours after the start of treatment (12 patients, 75%) than in the first 4 hours (three patients, 33%). Lactate was detected in five children (18%), all within the first 8 hours of treatment. CONCLUSION: In children, βOHB and AcAc accumulate in the brain during DKA, and they can be detected on MRS. Care should be taken in interpreting MRS results in patients with DKA to avoid erroneously attributing βOHB peaks to lactate.

The mechanism by which antagonist peptides inhibit T cell responses is unknown. Mice deficient in Src homology 2 domain-containing protein tyrosine phosphatase (SHP-1) have revealed its importance in the negative regulation of lymphocyte signaling. We investigated a possible role for SHP-1 in T cell antagonism and demonstrate, for the first time, a substantial increase in SHP-1 activity during antagonism of CD4+ T cells. Furthermore, the removal of functional SHP-1 prevents antagonism in these cells. Our data demonstrate that T cell antagonism occurs via a negative intracellular signal that is mediated by SHP-1.