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

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Genetic Counselor and Healthcare Interpreter Perspectives on the Role of Interpreters in Cancer Genetic Counseling.

Cancer genetic counseling (CGC) combines psychosocial counseling and genetic education provided by genetic counselors to patients and families who have a history of cancer and are considering or have undergone genetic testing for hereditary cancer syndromes. The quantity and complexity of information provided can be challenging for any patient, but is even more so for those with limited English proficiency (LEP). This exploratory study investigated healthcare interpreters' and genetic counselors' perspectives on the role of interpreters in providing care to LEP patients during CGC. Through a survey of 18 interpreters and conventional content analysis of semi-structured interviews with 11 interpreters and 10 GCs at two California public hospitals, we found that: 1) interpreters viewed their role as patient advocate, cultural broker, and emotional support, not simply a conduit; 2) interpreters were challenged by remote interpretation, lack of genetic knowledge, and the emotional content of encounters; 3) interpreters and GCs held conflicting views of the value of counselors' limited Spanish knowledge; and 4) trust, the foundation of the interpreter-provider dyad, was often lacking. The challenges identified here may result in poor healthcare experiences and outcomes for LEP patients. As genomics becomes more widespread and more LEP patients encounter CGC, the role of healthcare interpreters in facilitating effective communication must be further defined in order to facilitate better working relationships between interpreters and genetic counselors, and optimal communication experiences for patients

Cancer genetic counseling communication with low-income Chinese immigrants.

As genetics and genomics become part of mainstream medicine, these advances have the potential to either reduce or exacerbate health disparities. Relatively, little research has explored the quality of genetic counseling communication experienced by limited English proficiency patients, especially Chinese Americans. We observed and audio recorded genetic counseling appointments (n = 40) of low-income, limited English-proficient Chinese patients (n = 25) and conducted post-visit interviews (n = 17) using stimulated recall to examine patient understanding of the communication. Standard techniques based in grounded theory, including iterative data review and multiple coders, were used to analyze observation fieldnotes and interview transcripts and to identify these themes: (1) strong beliefs in environmental causes of cancer and skepticism about genetic causes, (2) willingness to undergo genetic testing despite skepticism of hereditary cause of cancer, (3) misunderstanding of key information needed to make informed decisions about testing and screening/prevention options, (4) variable quality of medical interpretation, and (5) selective family communication about cancer and genetic counseling and testing. Together, these themes describe substantial gaps in communication and identify the need for genetic counseling techniques and skills that enable counselors to communicate more effectively across language, literacy, and culture. Understanding the mechanisms of inheritance and the implications of genetic test results can be challenging for anyone, and it is exceptionally daunting for those who have limited English proficiency and/or low literacy. For Chinese immigrant patients to reap the full benefits of genetic counseling and testing, effective communication is essential. Research on interventions to improve communication is needed to ensure that disparities do not widen as genomic medicine reaches a more diverse population

Cancer genetic counseling communication with low-income Chinese immigrants.

As genetics and genomics become part of mainstream medicine, these advances have the potential to either reduce or exacerbate health disparities. Relatively, little research has explored the quality of genetic counseling communication experienced by limited English proficiency patients, especially Chinese Americans. We observed and audio recorded genetic counseling appointments (n = 40) of low-income, limited English-proficient Chinese patients (n = 25) and conducted post-visit interviews (n = 17) using stimulated recall to examine patient understanding of the communication. Standard techniques based in grounded theory, including iterative data review and multiple coders, were used to analyze observation fieldnotes and interview transcripts and to identify these themes: (1) strong beliefs in environmental causes of cancer and skepticism about genetic causes, (2) willingness to undergo genetic testing despite skepticism of hereditary cause of cancer, (3) misunderstanding of key information needed to make informed decisions about testing and screening/prevention options, (4) variable quality of medical interpretation, and (5) selective family communication about cancer and genetic counseling and testing. Together, these themes describe substantial gaps in communication and identify the need for genetic counseling techniques and skills that enable counselors to communicate more effectively across language, literacy, and culture. Understanding the mechanisms of inheritance and the implications of genetic test results can be challenging for anyone, and it is exceptionally daunting for those who have limited English proficiency and/or low literacy. For Chinese immigrant patients to reap the full benefits of genetic counseling and testing, effective communication is essential. Research on interventions to improve communication is needed to ensure that disparities do not widen as genomic medicine reaches a more diverse population

Information Mismatch: Cancer Risk Counseling with Diverse Underserved Patients.

As genetics and genomics become part of mainstream Medicine, these advances have the potential to reduce or exacerbate health disparities. Gaps in effective communication (where all parties share the same meaning) are widely recognized as a major contributor to health disparities. The purpose of this study was to examine GC-patient communication in real time, to assess its effectiveness from the patient perspective, and then to pilot intervention strategies to improve the communication. We observed 64 English-, 35 Spanish- and 25 Chinese-speaking (n = 124) public hospital patients and 10 GCs in 170 GC appointments, and interviewed 49 patients who were offered testing using the audio recordings to stimulate recall and probe specific aspects of the communication. Data analyses were conducted using grounded theory methods and revealed a fundamental mismatch between the information provided by GCs and the information desired and meaningful to patients. Several components of the communication that contributed to this mismatch and often resulted in ineffective communication included: (1) too much information; (2) complex terminology and conceptually difficult presentation of information; (3) information perceived as not relevant by the patient; (4) unintentional inhibition of patient engagement and question-asking; (5) vague discussions of screening and prevention recommendations. Our findings indicate a need to transform the standard model of genetic counseling communication using evidence-based principles and strategies from other fields of Medicine. The high rates of limited health literacy in the US, increasing access of diverse populations to genetic services, and growing complexity of genetic information have created a perfect storm. If not directly addressed, this convergence is likely to exacerbate health disparities in the genomic age