Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

EGFR-targeted treatments in patients with metastatic colorectal cancer: Experience of panitumumab.

Abstract Not Availabl

Society of Medical Oncology)

There is very little information about breast cancer characteristics, treatment choices, and survival among elderly patients. The purpose of this multicenter retrospective study was to examine the clinical, pathologic, and biologic characteristics of 620 breast cancer patients age 70 years or older. Between June 1991 and May 2012, 620 patients with breast cancer, recruited from 16 institutions, were enrolled in the retrospective study. Patients had smaller tumors at diagnosis; only 15% of patients had tumors larger than 5 cm. The number of patients who had no axillary lymph node involvement was 203 (32.7%). Ninety-three patients (15.0%) had metastatic disease at diagnosis. Patients were characterized by a higher fraction of pure lobular carcinomas (75.3%). The tumors of the elderly patients were also more frequently estrogen receptor (ER) positive (75.2%) and progesterone receptor (PR) positive (67.3%). The local and systemic therapies for breast cancer differed according to age. An association between age and overall survival has not been demonstrated in elderly patients with breast cancer. In conclusion, the biologic behavior of older patients with breast cancer differs from younger patients, and older patients receive different treatments

the Anatolian Society of Medical Oncology (ASMO)

BackgroundSoft tissue sarcomas (STSs) are rare malignant tumors of embryogenic mesoderm origin. Primary thoracic STSs account for a small percentage of all STSs and limited published information is available. This study aimed to identify the prognostic factors for thoracic STSs and evaluate the disease's clinical outcomes.MethodsThe medical records of 109 patients with thoracic STSs who were treated between 2003 and 2013 were retrospectively reviewed. Patients' survival rates were analyzed and potential prognostic factors evaluated.ResultsThe median follow-up period was 29 months (range: 1-121 months). STSs were most frequently localized on the chest wall (n = 42; 38.5%) and lungs (n = 42; 38.5%). The most common histological types were malignant fibrous histiocytoma (n = 23; 21.1%), liposarcoma (n = 17; 15.6%), and leiomyosarcoma (n = 16; 14.7%). The median survival time of all patients was 40.3 months (95% confidence interval, 14.22-66.37 months), with one and five-year survival rates of 93.4% and 63.5%, respectively. Univariate analysis of all groups revealed that metastatic stage, unresectability, tumor diameter of >10cm, tumor location other than the chest wall, and grade 3 diseases were predictable of poor survival. However, only grade 3 diseases and tumor location other than the chest wall were confirmed by multivariate analysis as poor prognostic factors.ConclusionsPrimary thoracic STSs are rarely seen malignant tumors. Our results indicated that patients with low-grade tumors and those localized on the chest wall often experienced better survival outcomes