A dual compartment cuvette system for correcting scattering in whole-cell absorbance spectroscopy of photosynthetic microorganisms.

Absorption spectroscopy is widely used to determine absorption and transmission spectra of chromophores in solution, in addition to suspensions of particles, including micro-organisms. Light scattering, caused by photons deflected from part or all of the cells or other particles in suspension, results in distortions to the absorption spectra, lost information and poor resolution. A spectrophotometer with an integrating sphere may be used to alleviate this problem. However, these instruments are not universally available in biology laboratories, for reasons such as cost. Here, we describe a novel, rapid, and inexpensive technique that minimises the effect of light scattering when performing whole-cell spectroscopy. This method involves using a custom made dual compartment cuvette containing titanium dioxide in one chamber as a scattering agent. Measurements were conducted of a range of different photosynthetic micro-organisms of varying cell size and morphology, including cyanobacteria, eukaryotic microalgae and a purple non-sulphur bacterium. A concentration of 1 mg ml-1 titanium dioxide, using a spectrophotometer with a slit width of 5 nm, produced spectra for cyanobacteria and microalgae similar (1-4% difference) to those obtained using an integrating sphere. The spectrum > 520 nm was similar to that with an integrating sphere with the purple non-sulphur bacterium. This system produced superior results to those obtained using a recently reported method, the application of the diffusing agent, Scotch™ Magic tape, to the side of the cuvette. The protocol can be completed in an equivalent period of time to standard whole-cell absorbance spectroscopy techniques, and is, in principle, suitable for any dual-beam spectrophotometer.

A Patient-Reported Outcome Instrument to Assess Symptom Burden and Predict Survival in Patients with Advanced Cancer: Flipping the Paradigm to Improve Timing of Palliative and End-of-Life Discussions and Reduce Unwanted Health Care Costs.

BACKGROUND: Discussions regarding palliative care and end-of-life care issues are frequently delayed past the time of usefulness, resulting in unwanted medical care. We sought to develop a patient-reported outcome (PRO) instrument that allows patients to voice their symptom burdens and facilitate timing of discussions. SUBJECTS, MATERIALS, AND METHODS: A seven-item PRO instrument (Cota Patient Assessed Symptom Score-7 item [CPASS-7]) covering physical performance status, pain, burden, and depression was administered (September 2015 through October 2016) with correlation to overall survival, correcting for time to complete survey since diagnosis. RESULTS: A total of 1,191 patients completed CPASS-7 at a median of 560 days following the diagnosis of advanced cancer. Of these patients, 49% were concerned that they could not do the things they wanted; 35% reported decreased performance status. Financial toxicity was reported by 39% of patients, with family burdens noted in 25%. Although depression was reported by 15%, 43% reported lack of pleasure. Pain was reported by 33%. The median CPASS-7 total symptom burden score was 16 (possible 0-112). With a median follow-up of 15 months from initial survey, 46% had died. Patients with symptom burden scores <29 and ≥29 had a 6-month overall survival rate of 87% and 67%, respectively, and 12-month survival rates of 72% and 50%. A one-point score increase resulted in a 1.8% increase in expected hazard. CONCLUSION: Patients with advanced cancer with higher levels of symptom burden, as self-reported on the CPASS-7, had inferior survival. The PRO facilitates identification of patients appropriate for reassessment of treatment goals and potentially palliative and end-of-life care in response to symptom burden concerns. IMPLICATIONS FOR PRACTICE: A seven-item patient-reported outcome (PRO) instrument was administered to 1,191 patients with advanced cancers. Patients self-reporting higher levels of physical and psychological symptom burden had inferior overall survival rates. High individual item symptom PRO responses should serve as a useful trigger to initiate supportive interventions, but when scores indicate global problems, discussions regarding end-of-life care might be appropriate.

Efficient synthesis and replication of diverse sequence libraries composed of biostable nucleic acid analogues.

Functional nucleic acids can be evolved in vitro using cycles of selection and amplification, starting from diverse-sequence libraries, which are typically restricted to natural or partially-modified polymer chemistries. Here, we describe the efficient DNA-templated synthesis and reverse transcription of libraries entirely composed of serum nuclease resistant alternative nucleic acid chemistries validated in nucleic acid therapeutics; locked nucleic acid (LNA), 2'-O-methyl-RNA (2'OMe-RNA), or mixtures of the two. We evaluate yield and diversity of synthesised libraries and measure the aggregate error rate of a selection cycle. We find that in addition to pure 2'-O-methyl-RNA and LNA, several 2'OMe-RNA/LNA blends seem suitable and promising for discovery of biostable functional nucleic acids for biomedical applications.

COVID-19 Vaccine Hesitancy and Acceptance Among Individuals With Cancer, Autoimmune Diseases, or Other Serious Comorbid Conditions: Cross-sectional, Internet-Based Survey.

BACKGROUND: Individuals with comorbid conditions have been disproportionately affected by COVID-19. Since regulatory trials of COVID-19 vaccines excluded those with immunocompromising conditions, few patients with cancer and autoimmune diseases were enrolled. With limited vaccine safety data available, vulnerable populations may have conflicted vaccine attitudes. OBJECTIVE: We assessed the prevalence and independent predictors of COVID-19 vaccine hesitancy and acceptance among individuals with serious comorbidities and assessed self-reported side effects among those who had been vaccinated. METHODS: We conducted a cross-sectional, 55-item, online survey, fielded January 15, 2021 through February 22, 2021, among a random sample of members of Inspire, an online health community of over 2.2 million individuals with comorbid conditions. Multivariable regression analysis was utilized to determine factors independently associated with vaccine hesitancy and acceptance. RESULTS: Of the 996,500 members of the Inspire health community invited to participate, responses were received from 21,943 individuals (2.2%). Respondents resided in 123 countries (United States: 16,277/21,943, 74.2%), had a median age range of 56-65 years, were highly educated (college or postgraduate degree: 10,198/17,298, 58.9%), and had diverse political leanings. All respondents self-reported at least one comorbidity: cancer, 27.3% (5459/19,980); autoimmune diseases, 23.2% (4946/21,294); chronic lung diseases: 35.4% (7544/21,294). COVID-19 vaccine hesitancy was identified in 18.6% (3960/21,294), with 10.3% (2190/21,294) declaring that they would not, 3.5% (742/21,294) stating that they probably would not, and 4.8% (1028/21,294) not sure whether they would agree to be vaccinated. Hesitancy was expressed by the following patients: cancer, 13.4% (731/5459); autoimmune diseases, 19.4% (962/4947); chronic lung diseases: 17.8% (1344/7544). Positive predictors of vaccine acceptance included routine influenza vaccination (odds ratio [OR] 1.53), trust in responsible vaccine development (OR 14.04), residing in the United States (OR 1.31), and never smoked (OR 1.06). Hesitancy increased with a history of prior COVID-19 (OR 0.86), conservative political leaning (OR 0.93), younger age (OR 0.83), and lower education level (OR 0.90). One-quarter (5501/21,294, 25.8%) had received at least one COVID-19 vaccine injection, and 6.5% (1390/21,294) completed a 2-dose series. Following the first injection, 69.0% (3796/5501) self-reported local reactions, and 40.0% (2200/5501) self-reported systemic reactions, which increased following the second injection to 77.0% (1070/1390) and 67.0% (931/1390), respectively. CONCLUSIONS: In this survey of individuals with serious comorbid conditions, significant vaccine hesitancy remained. Assumptions that the most vulnerable would automatically accept COVID-19 vaccination are erroneous and thus call for health care team members to initiate discussions focusing on the impact of the vaccine on an individual's underlying condition. Early self-reported side effect experiences among those who had already been vaccinated, as expressed by our population, should be reassuring and might be utilized to alleviate vaccine fears. Health care-related social media forums that rapidly disseminate accurate information about the COVID-19 vaccine may play an important role.

Expression of Alternative Nitrogenases in Rhodopseudomonas palustris Is Enhanced Using an Optimized Genetic Toolset for Rapid, Markerless Modifications.

The phototrophic bacterium Rhodopseudomonas palustris is emerging as a promising biotechnological chassis organism, due to its resilience to a range of harsh conditions, a wide metabolic repertoire, and the ability to quickly regenerate ATP using light. However, realization of this promise is impeded by a lack of efficient, rapid methods for genetic modification. Here, we present optimized tools for generating chromosomal insertions and deletions employing electroporation as a means of transformation. Generation of markerless strains can be completed in 12 days, approximately half the time for previous conjugation-based methods. This system was used for overexpression of alternative nitrogenase isozymes with the aim of improving biohydrogen productivity. Insertion of the pucBa promoter upstream of vnf and anf nitrogenase operons drove robust overexpression up to 4000-fold higher than wild-type. Transcript quantification was facilitated by an optimized high-quality RNA extraction protocol employing lysis using detergent and heat. Overexpression resulted in increased nitrogenase protein levels, extending to superior hydrogen productivity in bioreactor studies under nongrowing conditions, where promoter-modified strains better utilized the favorable energy state created by reduced competition from cell division. Robust heterologous expression driven by the pucBa promoter is thus attractive for energy-intensive biosyntheses suited to the capabilities of R. palustris. Development of this genetic modification toolset will accelerate the advancement of R. palustris as a biotechnological chassis organism, and insights into the effects of nitrogenase overexpression will guide future efforts in engineering strains for improved hydrogen production.

Differential impact of cognitive computing augmented by real world evidence on novice and expert oncologists.

INTRODUCTION: Cognitive computing point-of-care decision support tools which ingest patient attributes from electronic health records and display treatment options based on expert training and medical literature, supplemented by real world evidence (RWE), might prove useful to expert and novice oncologists. The concordance of augmented intelligence systems with best medical practices and potential influences on physician behavior remain unknown. METHODS: Electronic health records from 88 breast cancer patients evaluated at a USA tertiary care center were presented to subspecialist experts and oncologists focusing on other disease states with and without reviewing the IBM Watson for Oncology with Cota RWE platform. RESULTS: The cognitive computing "recommended" option was concordant with selection by breast cancer experts in 78.5% and "for consideration" option was selected in 9.4%, yielding agreements in 87.9%. Fifty-nine percent of non-concordant responses were generated from 8% of cases. In the Cota observational database 69.3% of matched controls were treated with "recommended," 11.4% "for consideration", and 19.3% "not recommended." Without guidance from Watson for Oncology (WfO)/Cota RWE, novice oncologists chose 75.5% recommended/for consideration treatments which improved to 95.3% with WfO/Cota RWE. The novices were more likely than experts to choose a non-recommended option (P < .01) without WfO/Cota RWE and changed decisions in 39% cases. CONCLUSIONS: Watson for Oncology with Cota RWE options were largely concordant with disease expert judged best oncology practices, and was able to improve treatment decisions among breast cancer novices. The observation that nearly a fifth of patients with similar disease characteristics received non-recommended options in a real world database highlights a need for decision support.

Development of a Precise, Clinically Relevant, Digital Classification Schema for Cancer.

PURPOSE: Health care transactions depend on the efficiency of digital codes. The International Classification of Diseases and Related Health Problems (ICD) coding system, which is the most commonly used digital system, fails to capture the complexity of oncologic diseases. Because important prognostic information such as cancer stage and genomic markers are missing, the potential for ICD codes to define and compare patient cohorts is severely limited. A more precise, clinically relevant, digital classification schema that incorporates prognostic elements would address these needs. METHODS: Working with cancer disease-specific experts, a new digital classification scheme, known as the Cota Nodal Address (CNA) system, was developed. The CNA has six components that define the disease of interest and incorporate all standard-of-care prognostic and predictive markers related to the particular cancer, including patient features. RESULTS: Properly sorted into homogeneous groupings of patients with similar prognostic characteristics, the CNA system facilitated big data analytic approaches, such as evaluations of population health, identification of variation in treatment decisions, and the enablement of value-based payment models. The schema has been applied to patients with breast cancer at a large tertiary cancer care hospital and a regional community cancer care network and has facilitated the creation and application of value-based payment models. CONCLUSION: The development and potential uses of a prognosis-based classification system are reviewed herein. Compared with ICD coding, the greater precision of the schema permits improved analyses of variance in treatment, outcomes, and costs in cancer care management.

Removal of both Ycf48 and Psb27 in Synechocystis sp. PCC 6803 disrupts Photosystem II assembly and alters Q(A)(-) oxidation in the mature complex.

The Photosystem II (PS II) assembly factors Psb27 and Ycf48 are transiently associated with PS II during its biogenesis and repair pathways. We investigated the function of these proteins by constructing knockout mutants in Synechocystis sp. PCC 6803. In ΔYcf48 cells, PS II electron transfer and stable oxygen evolution were perturbed. Additionally, Psb27 was required for photoautotrophic growth of cells lacking Ycf48 and assembly beyond the RC47 assembly complex in ΔYcf48:ΔPsb27 cells was impeded. Our results suggest the RC47 complex formed in ΔYcf48 cells is defective and that this deficiency is exacerbated if CP43 binds in the absence of Psb27.