Balanced mitochondrial function at low temperature is linked to cold adaptation in Drosophila species.

The ability of ectothermic animals to live in different thermal environments is closely associated with their capacity to maintain physiological homeostasis across diurnal and seasonal temperature fluctuations. For chill-susceptible insects, such as Drosophila, cold tolerance is tightly linked to ion and water homeostasis obtained through a regulated balance of active and passive transport. Active transport at low temperature requires a constant delivery of ATP and we therefore hypothesize that cold-adapted Drosophila are characterized by superior mitochondrial capacity at low temperature relative to cold-sensitive species. To address this, we investigated how experimental temperatures from 1 to 19°C affected mitochondrial substrate oxidation in flight muscle of seven Drosophila species and compared it with a measure of species cold tolerance (CTmin, the temperature inducing cold coma). Mitochondrial oxygen consumption rates measured using a substrate-uncoupler-inhibitor titration (SUIT) protocol showed that cooling generally reduced oxygen consumption of the electron transport system across species, as was expected given thermodynamic effects. Complex I respiration is the primary consumer of oxygen at non-stressful temperatures, but low temperature decreases complex I respiration to a much greater extent in cold-sensitive species than in cold-adapted species. Accordingly, cold-induced reduction of complex I respiration correlates strongly with CTmin. The relative contribution of other substrates (proline, succinate and glycerol 3-phosphate) increased as temperature decreased, particularly in the cold-sensitive species. At present, it is unclear whether the oxidation of alternative substrates can be used to offset the effects of the temperature-sensitive complex I, and the potential functional consequences of such a substrate switch are discussed.

Characterizing Distress and Identifying Modifiable Intervention Targets for Family Caregivers of Patients with Malignant Gliomas.

Background: Individuals caring for patients with malignant gliomas experience high rates of anxiety; however, an in-depth understanding of their distress and evidence-based interventions to target their needs are lacking. Objective: We conducted semistructured interviews with caregivers with elevated anxiety to characterize their drivers of anxiety, identify modifiable intervention targets, and capture their preferences for a psychosocial intervention. Design: From 9/2017 to 3/2019, we conducted semistructured interviews with 21 caregivers of patients with malignant gliomas, at time points following the patient's diagnosis or within one to three months after the patient's death. Setting/Subjects: Eligible caregivers in the United States had clinically significant anxiety as measured by a Hospital Anxiety and Depression Scale-Anxiety score >7. Measurements: Three independent coders employed thematic content analysis to analyze the qualitative data with NVivo 12, achieving high intercoder agreement (Kappa = 0.98). Results: On average, caregivers were 54.81 years old (SD = 10.85) with elevated anxiety (M = 10.90, SD = 3.25). We identified six themes in which caregivers described (1) coping through reassurance seeking or avoidance, (2) changes in their relationship with the patient, (3) challenges with social support, (4) vacillation between certainty and uncertainty regarding the future, (5) devaluation of self-care for the patients' needs, and (6) challenges communicating with the health care team. Caregivers were interested in an intervention soon after the patient's diagnosis, yet expressed concern about finding the time to participate. Conclusions: Emergent themes characterized the distress experienced by caregivers of patients with malignant gliomas and provided insight into their psychosocial intervention preferences. We identified evidence-based intervention components based on the modifiable factors arising from these themes.

Communication Differences between Oncologists and Palliative Care Clinicians: A Qualitative Analysis of Early, Integrated Palliative Care in Patients with Advanced Cancer.

BACKGROUND: Growing evidence demonstrates the benefits of early, integrated palliative care (PC) for patients with advanced cancer and their caregivers. Yet, data are lacking on the communication patterns within this model of care. OBJECTIVE: The goals of this study were to describe the content of patient-clinician discussions among patients receiving PC and to compare differences in discussion content between oncologists and PC clinicians. DESIGN: We conducted a qualitative observational analysis. SETTING/SUBJECTS: We included patients with incurable lung and esophageal cancer enrolled in a randomized trial of early, integrated PC versus usual oncology care. We analyzed 68 audio-recorded clinic visits (34 oncologist visits; 34 PC clinician visits) immediately after patients' (N = 19) first and second cancer progressions. We examined themes of clinician communication, comparing the content and frequency of discussions between oncologists and PC clinicians. RESULTS: Although both oncology and PC clinicians discussed symptom management, medical understanding, and treatment decision making with patients at nearly all postprogression visits, PC clinicians tended to assess patient understanding of the treatment process and prognosis more often than oncologists. PC clinicians addressed patient coping, caregiver experiences and needs, and advance care planning more frequently than oncologists. CONCLUSION: PC clinicians play a distinct, complementary role to oncologists in providing care for patients with advanced cancer and their caregivers. PC clinicians tend to assess and elaborate on patient understanding of prognosis and treatment and emphasize effective coping, caregiver needs, and advance care planning. These results illuminate the communication elements by which early, integrated PC may improve patient and caregiver outcomes.

Coupling the N-CODES system with actual nurse decision-making.

Nurses must be involved in the development and testing of clinical decision support systems if systems that fit into the actual clinical decision-making process and the flow of practice are to be designed. This article discusses the first trial of N-CODES, the Nurse Decision Support System. This system is designed to assist nurses, particularly novices, to make clinical decisions. The adequacy of the theoretical framework and selected aspects of the knowledge base were examined. Twelve nurses participated. Results indicated that revision of the theoretical framework is necessary if it is to be a fair representation of nurse's decision-making. The sequencing of information seems appropriate but the process of developing the knowledge base must be made more transparent to nurse users. After modifications, the next trial will test actual clinical use.

Evolutionary analysis of Arabidopsis, cyanobacterial, and chloroplast genomes reveals plastid phylogeny and thousands of cyanobacterial genes in the nucleus.

Chloroplasts were once free-living cyanobacteria that became endosymbionts, but the genomes of contemporary plastids encode only approximately 5-10% as many genes as those of their free-living cousins, indicating that many genes were either lost from plastids or transferred to the nucleus during the course of plant evolution. Previous estimates have suggested that between 800 and perhaps as many as 2,000 genes in the Arabidopsis genome might come from cyanobacteria, but genome-wide phylogenetic surveys that could provide direct estimates of this number are lacking. We compared 24,990 proteins encoded in the Arabidopsis genome to the proteins from three cyanobacterial genomes, 16 other prokaryotic reference genomes, and yeast. Of 9,368 Arabidopsis proteins sufficiently conserved for primary sequence comparison, 866 detected homologues only among cyanobacteria and 834 other branched with cyanobacterial homologues in phylogenetic trees. Extrapolating from these conserved proteins to the whole genome, the data suggest that approximately 4,500 of Arabidopsis protein-coding genes ( approximately 18% of the total) were acquired from the cyanobacterial ancestor of plastids. These proteins encompass all functional classes, and the majority of them are targeted to cell compartments other than the chloroplast. Analysis of 15 sequenced chloroplast genomes revealed 117 nuclear-encoded proteins that are also still present in at least one chloroplast genome. A phylogeny of chloroplast genomes inferred from 41 proteins and 8,303 amino acids sites indicates that at least two independent secondary endosymbiotic events have occurred involving red algae and that amino acid composition bias in chloroplast proteins strongly affects plastid genome phylogeny.