Inflammatory biomarker-based clinical practice in patients with pneumonia: A systematic review of randomized controlled trials.

Objectives: Biomarker-based clinical practice is currently gaining ground and increasingly affects decision making. A variety of biomarkers have been studied through the years and some of them have already an established role in modern medicine, such as procalcitonin (PCT) which has been proposed to reduce antibiotic exposure. We purposed to systematically review all biomarkers examined for guiding the clinical practice in patients with pneumonia. METHODS: A systematic review on PubMed was performed on April 2023 by two independent researchers using the PRISMA guidelines. Randomized trials which enrolled patients with pneumonia and compared biomarker-guided strategies to standard of care were included. RESULTS: 1242 studies were recorded, from whom 16 were eligible for this study. 14 studies investigated PCT as a biomarker. From these, 8 studies reported on community acquired pneumonia (CAP), 2 on ventilator associated pneumonia (VAP), 1 on aspiration pneumonia, 1 on hospital acquired pneumonia (HAP) and 2 on exacerbation of chronic obstructive pulmonary disease (ECOPD). There was 1 study, referred to VAP, that investigated interleukin-1ß (IL-1ß) and interleukin-8 (IL-8) and 1 study that reported the role of C-reactive protein (CRP) in ECOPD. In a total of 4751 patients in 15 studies, the biomarker-based approach did not lead to increased mortality [OR: 0.998 (95%CI: 0.74-1.34, p value: 0.991). I2:19%]. Among different types of pneumonia and time-points of assessment, biomarker-guided practice appeared to improve antibiotic-related outcomes, such as rate of antibiotic prescription, duration of antibiotic therapy and rate of antibiotic exposure, while 5 studies reported a possible decrease in antibiotic-related adverse effects. Biomarker-guided practice did not seem to lead in an increase in other adverse outcomes such as need for hospitalization and duration of hospitalization. However, the included studies have high risk of bias mainly due to improper blinding of participants/personnel and outcome assessors. CONCLUSION: Biomarker-guided clinical practice improves provided healthcare, in terms of reduced antibiotic consumption with no inferiority to mortality, relapses and exacerbations in patients with different types of pneumonia. Thus, such approaches should be further evaluated to achieve personalized medicine.

Raman amplification and lasing in SiGe waveguides.

We describe the first observation of spontaneous Raman emission, stimulated amplification, and lasing in a SiGe waveguide. A pulsed optical gain of 16dB and a lasing threshold of 25 W peak pulse power (20 mW average) is observed for a Si1-xGex waveguide with x=7.5%. At the same time, a 40 GHz frequency downshift is observed in the Raman spectrum compared to that of a silicon waveguide. The spectral shift can be attributed to the combination of composition- and strain-induced shift in the optical phonon frequency. The prospect of Germanium-Silicon-on-Oxide as a flexible Raman medium is discussed.

Adriamycin and cis-platinum as first-line treatment in unresectable locally advanced or metastatic adult soft-tissue sarcomas.

Standard chemotherapy in advanced adult soft-tissue sarcomas (STS) has not yet been established. We evaluated the efficacy and toxicity of the combination of adriamycin (ADR) and cis-platinum (CDDP) as first-line treatment in nonoperable locally advanced or metastatic adult STS. Thirty patients were treated with CDDP 100 mg/m2 on day 1 and ADR 75 mg/m2 equally divided on days 1 to 3, every 3 weeks for 6 cycles. Patients were evaluated for response, toxicity, and survival, while resectability of residual disease was also assessed after the third cycle and the end of chemotherapy. No complete response was observed. Five patients (16.7%, 95% CI: 2.5%-31%) achieved partial response, 16 patients (53.3%, 95% CI: 34%-72%) had stable disease and 9 patients (30%, 95% CI: 13%-47%) had progressive disease. The overall median survival was 11.5 months (range, 4-96 months), and the median time to disease progression was 6 months (range, 0-96 months). Furthermore, two patients with PR and six patients with stable disease underwent further surgery followed by radiotherapy in four of them. At present, 5 patients remain free of relapse for 96, 90, 72, 60, and 48 months, respectively. Treatment-related toxicity was acceptable, with moderate myelosuppression and alopecia as the main adverse events. The ADR/CDDP regimen was well tolerated, but it did not achieve a high response rate. However, patients with resectable disease after chemotherapy achieved long-term survival. Further studies are needed to evaluate the role of combined-modality treatments in the management of patients with advanced STS.

Phase-matching and Nonlinear Optical Processes in Silicon Waveguides.

The efficiency of four-wave-mixing arising from Raman and non-resonant nonlinear susceptibilities in silicon waveguides is studied in the 1.3 - 1.8microm regime. The wavelength conversion efficiency is dominated by the Raman contribution to the nonlinear susceptibility, and high conversion efficiencies can be achieved under the phase-matching condition. In this context, dispersion in silicon waveguides is analyzed and it is shown that phase-matching is achieved in properly engineered waveguides where birefringence compensates for material dispersion. Finally the sensitivity of the phase mismatch to fabrication-induced errors in waveguide dimensions is quantified.