Safely increasing the proportion of patients with community-acquired pneumonia treated as outpatients: an interventional trial.

BACKGROUND: Patients with community-acquired pneumonia who are at low risk for short-term mortality can be identified using a validated prediction rule, the Pneumonia Severity Index. Such patients should be candidates for outpatient treatment, yet many are hospitalized. OBJECTIVE: To assess a program to safely increase the proportion of low-risk patients with pneumonia treated at home. METHODS: The intervention provided physicians with the Pneumonia Severity Index score and corresponding mortality risk for eligible patients and offered enhanced visiting nurse services and the antibiotic clarithromycin. Prospectively enrolled, consecutive low-risk patients with pneumonia presenting to an emergency department during the intervention period (n = 166) were compared with consecutive retrospective controls (n = 147) identified during the prior year. A second group of 208 patients from the study hospital who participated in the Pneumonia Patient Outcomes Research Team cohort study served as controls for patient-reported measures of recovery. RESULTS: There were no significant baseline differences between patients in the intervention and control groups. The percentage initially treated as outpatients increased from 42% in the control period to 57% in the intervention period (36% relative increase; 95% confidence interval, 8%-72%; P = .01). However, more outpatients during the intervention period were subsequently admitted to the study hospital (9% vs 0%). When any admission to the study hospital within 4 weeks of presentation was considered, there was a trend toward more patients receiving all their care as outpatients in the intervention group (42% vs 52%; 25% relative increase; 95% confidence interval -2% to 59%; P = .07). No patient in the intervention group died in the 4-week follow-up period. Symptom resolution and functional status were not diminished. Satisfaction with overall care was similar, but patients treated in the outpatient setting during the intervention were less frequently satisfied with the initial treatment location than comparable control patients (71% vs 90%; P = .04). CONCLUSIONS: Use of a risk-based algorithm coupled with enhanced outpatient services effectively identified low-risk patients with community-acquired pneumonia in the emergency department and safely increased the proportion initially treated as outpatients. Outpatients in the intervention group were more likely to be subsequently admitted than were controls, lessening the net impact of the intervention.

Developmental expression of protein kinase C activity in Schistosoma mansoni.

The multicellular parasite Schistosoma mansoni undergoes complex physiologic changes during development from infective cercariae to adult worms in the mammalian host. The present study examined changes in protein kinase C (PKC) activity in S. mansoni during parasite maturation. Activation of PKC required Ca+2, phosphatidylserine, and either diacylglycerol or phorbol ester similar to mammalian PKC enzyme. A nine-fold increase in total PKC activity was found in adult worms as compared with larval parasites. Transformation of infective cercariae to parasitic schistosomula was associated with translocation of PKC activity from the cytosolic to membrane fraction. Tegumental extracts demonstrated significant PKC activity, suggesting a signal transduction system in the surface of the parasite. These data indicate that PKC activity is differentially expressed during parasite development and may have critical roles in regulation of cellular events in S. mansoni.

Schistosoma mansoni: characterization of phosphoinositide response.

Signal transduction pathways may have important regulatory roles in cellular events in the human parasite Schistosoma mansoni. The presence of the phosphoinositide response in S. mansoni was examined by radiolabeling intact worms with 20 muCi of [3H]myoinositol for 24 hr and stimulating parasites with 25 mM NaF and 10 microM AlCl3 in the presence of 10 mM LiCl. Total inositol phosphates were increased within 2 min and maximal accumulation was achieved after 30 min. Similar results were seen with the non-hydrolyzable GTP analogues GTP gamma S and GppNHp while only minimal changes were detected with GMP. Neomycin inhibited NaF-induced inositol phosphate production. NaF stimulated a significant 3.6-fold increase of inositol phosphates in females compared to males. These data suggest that stimulation of guanine nucleotide-binding regulatory proteins activates phospholipase C resulting in production of inositol phosphates in S. mansoni.

Electronic averaging of one-dimensional television pictures.

Often the data which one would like to record by means of a television system are only one-dimensional, for example, optical spectra or, in this case, picosecond light pulse measurement by the nonlinear photoelectric effect. For such data, a significant increase in signal-to-noise ratio and dynamic range can be obtained by averaging over the redundant dimension. A box-car system has been developed for performing such an average using the standard television raster. Particular attention was paid to the problem of accurate dc restoration of the video signal.