Discrepancy in responses to the surprise question between hemodialysis nurses and physicians, with focus on patient clinical characteristics: A comparative study.

INTRODUCTION: The surprise question (SQ) "Would I be surprised if this patient died within the next xx months" can be used by different professions to foresee the need of serious illness conversations in patients approaching end of life. However, little is known about the different perspectives of nurses and physicians in responses to the SQ and factors influencing their appraisals. The aim was to explore nurses' and physicians' responses to the SQ regarding patients on hemodialysis, and to investigate how these answers were associated with patient clinical characteristics. METHODS: This comparative cross-sectional study included 361 patients for whom 112 nurses and 15 physicians responded to the SQ regarding 6 and 12 months. Patient characteristics, performance status, and comorbidities were obtained. Cohen's kappa was used to analyze the interrater agreement between nurses and physicians in their responses to the SQ and multivariable logistic regression was applied to reveal the independent association to patient clinical characteristics. FINDINGS: Proportions of nurses and physicians responding to the SQ with "no, not surprised" was similar regarding 6 and 12 months. However, there was a substantial difference concerning which specific patient the nurses and physicians responded "no, not surprised", within 6 (κ = 0.366, p < 0.001, 95% CI = 0.288-0.474) and 12 months (κ = 0.379, p < 0.001, 95% CI = 0.281-0.477). There were also differences in the patient clinical characteristics associated with nurses' and physicians' responses to the SQ. DISCUSSION: Nurses and physicians have different perspectives in their appraisal when responding to the SQ for patients on hemodialysis. This may reinforce the need for communication and discussion between nurses and physicians to identify the need of serious illness conversations in patients approaching the end of life, in order to adapt hemodialysis care to patient preferences and needs.

A comparative study for the isolation of exogenous trace DNA from fingernails.

Often fingernails from a victim or suspect involved in a physical assault, such as murder or sexual assault, are submitted to crime laboratories for DNA testing of foreign/exogenous biological material; however, very few studies have been conducted comparing the effectiveness of different sampling methods on the removal of foreign/exogenous DNA while minimizing the fingernail endogenous DNA. In this study three different sampling methods (swabbing, PBS soak, and PrepFiler® lysis buffer soak) were compared in order to identify one that minimizes the amount of endogenous DNA removed and maximizes the amount of foreign/exogenous male DNA removed. The samples were processed using the Tecan HIDEVO150 robot in order to reduce analyst time and the DNA mixtures were interpreted using the probabilistic genotyping software STRmix™. For each sampling method the quantity of male DNA, the mixture proportions, the number of foreign/exogenous male alleles detected, the amount of DNA degradation, and the discrimination power via the likelihood ratio obtained for the foreign/exogenous male DNA donor were determined and compared. The PrepFiler® lysis buffer soak and swabbing sampling methods appear to be equally effective at removing foreign/exogenous DNA from fingernails; however, the lysis buffer soak sampling method extracts more female endogenous DNA from the fingernail and the female DNA is degraded. Marginally higher likelihood ratios were obtained for the swab samples versus the PrepFiler® lysis buffer soak samples; therefore, it was determined that the swabbing sampling method was the best sampling method for the recovery of foreign exogenous DNA from fingernails while minimizing the amount of endogenous DNA removed.

Constructing universal multiplex PCR systems for comparative genotyping.

Analysis of length polymorphisms at STR loci in the human genome has become a standard approach for comparative genotyping in many areas including disease research and diagnostics, parentage assessment, investigations of human diversity, and forensic science. The simultaneous analysis of multiple STR loci through multiplex PCR and multicolor fluorescence detection offers sample conservation, high throughput, and automated genetic analysis. Careful design and optimization of tetranucleotide STR multiplexes has led to reliable, standardized systems that powerfully differentiate and distinguish individual human DNA profiles. The development of these multiplex systems involved a rigorous experimental strategy that included careful selection of PCR primer sequences (for yield, specificity, and multiplex compatability), along with optimization of PCR component concentrations, thermal cycling parameters, and fluorescence detection conditions. This developmental approach rendered well-characterized DNA typing systems that are high performing (sensitive, specific, and balanced), optimized to universal parameters (same reaction conditions), resilient to fluctuations in reaction conditions, and simple to implement and use routinely.

TWGDAM validation of AmpFlSTR PCR amplification kits for forensic DNA casework.

Laboratory procedures used in short tandem repeat (STR) analysis were subjected to various scenarios that assessed reliability and identified potential limitations. These validation studies were designed as recommended by the Technical Working Group on DNA Analysis Methods (TWGDAM) and the DNA Advisory Board (DAB) (17,18). Various DNA samples were amplified by the polymerase chain reaction (PCR) using AmpFlSTR PCR Amplification Kits (i.e., AmpFlSTR Green I, Profiler, Profiler Plus, and COfiler kits), detected with ABI Prism instrumentation, and analyzed using GeneScan and Genotyper software. Data acquired in these studies reinforced an existing body of knowledge and expertise regarding application and interpretation of STR typing in the forensic science community. Consistent STR genotypes were detected in various body tissues and fluids. Inter-laboratory comparisons produced concordant genotype results. Quantitative interpretational aids for DNA mixtures were characterized. Ability of the typing systems to type potentially compromised samples reliably was evaluated. Nonprobative case evidentiary DNA was successfully amplified, genotyped, and interpreted. Potential limitations or cautionary factors in the interpretation of minimal fluorescence intensity were demonstrated. Differential amplification between loci was observed when PCR was inhibited; preferential amplification typically was not. Single AmpFlSTR locus amplification did not offer consistent benefit over AmpFlSTR multiplexing, even in cases of DNA degradation or PCR inhibition. During rigorous evaluation, AmpFlSTR PCR Amplification Kits reproducibly yielded sensitive and locus-specific results, as required in routine forensic analyses.