Rapid Visualization of Chemically Related Compounds Using Kendrick Mass Defect As a Filter in Mass Spectrometry Imaging.

Kendrick mass defect (KMD) analysis is widely used for helping the detection and identification of chemically related compounds based on exact mass measurements. We report here the use of KMD as a criterion for filtering complex mass spectrometry data set. The method allow automated, easy and efficient data processing, enabling the reconstruction of 2D distributions of families of homologous compounds from MSI images. We show that KMD filtering, based on in-house software, is suitable and robust for high resolution (full width at half-maximum, fwhm, at m/z 410 of 20 000) and very high-resolution (fwhm, at m/z 410 of 160 000) MSI data. This method has been successfully applied to two different types of samples, bacteria cocultures, and brain tissue sections.

Clinical staging of HIV-related illness in Mozambique: performance of nonphysician clinicians based on direct observation of clinical care and implications for health worker training.

INTRODUCTION: In Mozambique, clinical staging may be the primary determinant of HIV/AIDS treatment decisions, and the task of staging commonly falls to nonphysician clinicians (técnicos de medicina). Two years after the first Mozambican técnicos were trained in HIV/AIDS care, the quality of their performance in clinical staging was unknown. METHODS: Expert clinicians observed 127 clinical encounters conducted by a randomly selected national sample of 44 técnicos and compared observed clinical staging decisions to World Health Organization and Mozambican national norms. They also reviewed relevant Mozambican in-service training curricula in HIV/AIDS care. RESULTS: Observers agreed with fewer than half (44.1%) of the técnicos' stage-defining diagnoses. Misclassification or misdiagnosis of 3 complaints (weight loss, fever, and diarrhea) accounted for the majority of the observed errors. Review of health worker curricula determined that observed staging errors reflected content errors and omissions in the técnicos' in-service HIV/AIDS training and constraints in local laboratory and imaging capacity. DISCUSSION: In response to these findings, the Mozambican Ministry of Health has revised the técnicos' scope of work and has developed new guidelines, curriculum materials, and training strategies to improve the quality of clinical staging and opportunistic infection diagnosis in Mozambique.