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Plants need to protect themselves from excess light, which causes photo-oxidative damage and lowers the efficiency of photosynthesis. Photosystem II subunit S (PsbS) is a pH sensor protein that plays a crucial role in plant photoprotection by detecting thylakoid lumen acidification in excess light conditions via two lumen-faced glutamates. However, how PsbS is activated under low-pH conditions is unknown. To reveal the molecular response of PsbS to low pH, here we perform an NMR, FTIR and 2DIR spectroscopic analysis of Physcomitrella patens PsbS and of the E176Q mutant in which an active glutamate has been replaced. The PsbS response mechanism at low pH involves the concerted action of repositioning of a short amphipathic helix containing E176 facing the lumen and folding of the luminal loop fragment adjacent to E71 to a 3 10 -helix, providing clear evidence of a conformational pH switch. We propose that this concerted mechanism is a shared motif of proteins of the light-harvesting family that may control thylakoid inter-protein interactions driving photoregulatory responses. Photosystem II subunit S (PsbS) senses thylakoid lumen acidification when plants are exposed to excess light. Here the authors use NMR and IR spectroscopy to show that low pH causes repositioning of an amphipathic helix and folding of a loop involving critical pH sensing glutamate residues in PsbS.

Background The purpose of this study is to determine the prevalence of diabetes distress and its relationship with health behaviours and clinical outcomes in low-income patients. Methods Secondary analyses were conducted using baseline data from a clinical trial evaluating a diabetes self-management intervention. Interviews were conducted with 666 participants receiving care at nine safety net clinics in Missouri. Distress was measured using the Diabetes Distress Scale, and outcomes included medication adherence, physical activity, nutrition and clinical biomarkers (haemoglobin A1C (HbA1C), blood pressure, low-density lipoprotein (LDL) cholesterol). Results In a sample of 666 participants, 14.1% and 27.3% of patients were identified as highly and moderately distressed, respectively, with higher rates among younger, female and lower income patients. When compared with moderately and no distress groups, highly distressed patients were less adherent to medications (20.7% vs 29.9% vs 39.4%, p<0.001) and had higher HbA1C values (9.3% (SD=2.0) vs 8.2% (SD=1.8) vs 7.8% (SD=1.7), p<0.001), diastolic blood pressure (81.8 (SD=9.4) vs 80.2 (9.7) vs 78.9 (SD=8.8), p=0.02) and LDL cholesterol (104.6 (SD=42.4) vs 97.2 (34.3) vs 95.5 (37.9)) In multivariable analyses, high and moderate distress were associated with lower medication adherence (OR=0.44; 0.27 to 0.23, p=0.001) and (OR=0.58; 0.42 to 0.79; p=0.001), respectively, and higher HbA1C in only the highly distressed group (B=1.3; 0.81 to 1.85; p<0.001) compared with the no distress group. Conclusions Diabetes distress is prevalent and linked to poorer adherence to health behaviours and glycemic control in a sample of patients receiving care from low-income clinics.

ABSTRACT BACKGROUND We compared two implementation approaches for a health literacy diabetes intervention designed for community health centers. METHODS A quasi-experimental, clinic-randomized evaluation was conducted at six community health centers from rural, suburban, and urban locations in Missouri between August 2008 and January 2010. In all, 486 adult patients with type 2 diabetes mellitus participated. Clinics were set up to implement either: 1) a clinic-based approach that involved practice re-design to routinely provide brief diabetes education and counseling services, set action-plans, and perform follow-up without additional financial resources [CARVE-IN]; or 2) an outsourced approach where clinics referred patients to a telephone-based diabetes educator for the same services [CARVE-OUT]. The fidelity of each intervention was determined by the number of contacts with patients, self-report of services received, and patient satisfaction. Intervention effectiveness was investigated by assessing patient knowledge, self-efficacy, health behaviors, and clinical outcomes. RESULTS Carve-out patients received on average 4.3 contacts (SD = 2.2) from the telephone-based diabetes educator versus 1.7 contacts (SD = 2.0) from the clinic nurse in the carve-in arm ( p  < 0.001). They were also more likely to recall setting action plans and rated the process more positively than carve-in patients ( p  < 0.001). Few differences in diabetes knowledge, self-efficacy, or health behaviors were found between the two approaches. However, clinical outcomes did vary in multivariable analyses; carve-out patients had a lower HbA1c ( β  = −0.31, 95 % CI −0.56 to −0.06, p  = 0.02), systolic blood pressure ( β  = −3.65, 95 % CI −6.39 to −0.90, p  = 0.01), and low-density lipoprotein (LDL) cholesterol ( β  = −7.96, 95 % CI −10.08 to −5.83, p  < 0.001) at 6 months. CONCLUSION An outsourced diabetes education and counseling approach for community health centers appears more feasible than clinic-based models. Patients receiving the carve-out strategy also demonstrated better clinical outcomes compared to those receiving the carve-in approach. Study limitations and unclear causal mechanisms explaining change in patient behavior suggest that further research is needed.

Background: Patient misunderstanding of prescription drug label instructions is a leading cause of medication errors. Among Latino patients, limited English proficiency is a major barrier to comprehension of medication instructions. Objectives: To determine the availability of Spanish prescription drug label instructions. Research Design: A telephone survey was conducted in 4 states selected due to either a rapid growth in their Latino population (GA, NC) or a large, existing Latino population (CO, TX). Subjects: A list of retail pharmacies was obtained from each state board of pharmacy. A simple random sample of 10 percent of pharmacies within each state was generated (N = 764). Measures: The ability of pharmacies to print prescription instructions in Spanish and the process for translating instructions. Results: Two hundred sixty-seven (34.9%) pharmacies reported no translation services, 166 (21.7%) reported limited translation services, and 331 (43.3%) stated they were able to perform translations. In bivariate analyses, significant differences between pharmacy characteristics and the availability of Spanish labels were noted. In multivariate analysis including pharmacy type, location, percentage Latino population, and state, only metropolitan location was found to be a significant independent predictor of pharmacies offering full Spanish translation services (adjusted odds ratio: 1.72, 95% confidence interval: 1.04-2.84). Conclusions: The majority of pharmacies surveyed offered limited or no translation services. Lack of translation services is not isolated to rural areas or locations with a marginal Latino population. Spanish-speaking patients encounter barriers to acquiring instructions that support the safe and effective use of medications.

This short review describes how solid-state NMR has provided a mechanistic and electronic picture of pigment–protein and pigment–pigment interactions in photosynthetic antenna complexes. NMR results on purple bacterial antenna complexes show how the packing of the protein and the pigments inside the light-harvesting oligomers induces mutual conformational stress. The protein scaffold produces deformation and electrostatic polarization of the BChl macrocycles and leads to a partial electronic charge transfer between the BChls and their coordinating histidines, which can tune the light-harvesting function. In chlorosome antennae assemblies, the NMR template structure reveals how the chromophores can direct their self-assembly into higher macrostructures which, in turn, tune the light-harvesting properties of the individual molecules by controlling their disorder, structural deformation, and electronic polarization without the need for a protein scaffold. These results pave the way for addressing the next challenge, which is to resolve the functional conformational dynamics of the lhc antennae of oxygenic species that allows them to switch between light-emitting and light-energy dissipating states.

We report the application of NMR dynamic spectral editing for probing the structure and dynamics of molecular constituents in fresh, intact cells and in freshly prepared thylakoid membranes of Chlamydomonas reinhardtii (Cr.) green algae. For isotope labeling, wild-type Cr. cells were grown on 13C acetate-enriched minimal medium. 1D 13C J-coupling based and dipolar-based MAS NMR spectra were applied to distinguish 13C resonances of different molecular components. 1D spectra were recorded over a physiological temperature range, and whole-cell spectra were compared to those taken from thylakoid membranes, evaluating their composition and dynamics. A theoretical model for NMR polarization transfer was used to simulate the relative intensities of direct, J-coupling, and dipolar-based polarization from which the degree of lipid segmental order and rotational dynamics of the lipid acyl chains were estimated. We observe that thylakoid lipid signals dominate the lipid spectral profile of whole algae cells, demonstrating that with our novel method, thylakoid membrane characteristics can be detected with atomistic precision inside intact photosynthetic cells. The experimental procedure is rapid and applicable to fresh cell cultures, and could be used as an original approach for detecting chemical profiles, and molecular structure and dynamics of photosynthetic membranes in vivo in functional states.

Abstract INTRODUCTION Heart Rate Variability (HRV), the variation in time between each heartbeat, is a proxy for vagus nerve function and validated indicator of cardiovascular health. Lower HRV is associated with increased risk of cardiac events and greater vulnerability to psychological stress. Fatigue is a common, frustrating and persistent symptom for IBD patients, with multifaceted mechanisms including nutrient deficiencies, inflammation, and poor sleep. Lower HRV is associated with higher fatigue in patients with cancer and myalgic encephalomyelitis. We postulate lower HRV could be associated with fatigue in IBD patients. METHODS Adults recruited from an outpatient IBD clinic wore a FitBit Inspire 2.0 for 14 days to monitor nighttime total time asleep, restlessness (# of ~30 second awakenings), and HRV (RMSSD in milliseconds (ms)). At baseline, weeks 1 and 2, participants completed the IBD Fatigue Scale and Harvey Bradshaw Index (HBI) or Simple Colitis Clinical Activity Index (SCCAI). Baseline laboratory testing for c-reactive protein (CRP), vitamins B12 and D, and ferritin was done. Averages for HRV and sleep metrics were computed for the 14-day period. Pearson’s correlations assessed relationships between all study variables (any p < .10). Then, partial correlations calculated the relationship between HRV and fatigue scores while controlling for identified confounding variables. We report an interim analysis. RESULTS 41 participants (63% female, 72.5% White, 92.7% non-Hispanic, 61% Crohn’s, 40.02 (SD=14.18) yrs old). Most (>75%) were in remission (HBI/SCCAI< 4). 34% had B12< 400 pg/mL, 20% vitamin D< 30 ng/mL, 54% ferritin< 50 ng/mL. Participants slept an average of 6.6 hours with 24.1(5.48) awakenings per night. All reported fatigue, with 43.9% having severe levels. Fatigue severity and impact remained consistent over the study (p=.106). Average HRV was 31.79(19.0) ms (Range: 11 - 92). Older patients had lower HRV (r= -0.34, p=.025) with no gender differences. Patients who reported more fatigue had higher CRP (r= 0.29), more active IBD symptoms (r= 0.62), and spent more time asleep (r= 0.20). When controlling for these variables and age, IBD patients with lower HRV reported significantly more global fatigue (r= -0.38, p=.041). The relationship between HRV and fatigue was larger for lower HRV and fatigue impact (r= -0.37, p=.047) than fatigue severity (r= -0.30, p=.11). No relationships existed for restlessness, vitamins B12 or D, or ferritin and fatigue. CONCLUSIONS When controlling for other contributors, patients with IBD and lower HRV reported more significant global fatigue and impact of fatigue on daily functioning. Findings may suggest lower HRV increases physical feelings of fatigue and reduces ability to manage fatigue impacts. Increasing HRV, e.g., with biofeedback training, may be a way to improve fatigue symptoms and management in IBD.

Abstract Introduction Medical trauma related to IBD (IBD-PTS) affects approximately 25% of patients and is associated with poor outcomes. Prior studies identify common hospitalization experiences as potentially traumatic but have not measured risk relationships for the development of IBD-PTS. We aim to investigate what aspects of hospitalizations may increase the chance of medical trauma and IBD-PTS development. Methods Adult patients with IBD enrolled in the IBD Partners database were recruited. Study specific questionnaires included PTSD checklist, 5th edition (PCL-5), patient experience questionnaire, and items about the patient’s most stressful hospitalization and nonhospital sources of medical trauma. Established criteria for the PCL-5 identified significant IBD-PTS symptoms (re-experiencing, avoidance, mood change, hyperarousal, global diagnosis). Select disease and treatment information was obtained from the main IBD Partners dataset. Univariate and multivariate statistics evaluated the relationships between hospitalization data and IBD-PTS. Results There were 639 participants with at least 1 hospitalization for IBD included. Approximately two-thirds had Crohn’s disease; most were White, non-Hispanic, female, middle-aged, and reported their IBD as being in remission. Forty percent of patients stated a hospitalization was a source of IBD-PTS. Frequent anxiety while hospitalized increased the odds of IBD-PTS 2 to 4 times; similar relationships existed for pain/pain control. Higher quality communication, information, and listening skills reduced the odds of IBD-PTS, albeit marginally. Conclusions Patients with IBD consistently cite hospitalizations as potential sources of medical trauma. Poorly managed anxiety and pain demonstrate the greatest chance for IBD-PTS development. Gender and racial/ethnic differences emerged for these risks. Positive interactions with the medical team may help mitigate in-hospital IBD-PTS development. Lay Summary This study finds IBD patients with the poorest hospital experiences and those with poor pain and anxiety control are at the highest risk of developing post-traumatic stress disorder symptoms due to medical trauma. Medical staff behavior is an important consideration.

Background Post-traumatic stress (PTS) is the psycho-physiological response to a traumatic or life-threatening event and is implicated in inflammatory bowel disease (IBD). IBD-PTS is present in up to 30% of white, non-Hispanic patients. The rates of IBD in Asian populations are expanding, making the exploration of IBD-PTS in this population imperative. Methods Adult patients of South/Southeast (S/SE) Asian decent with IBD for more than 6 months were recruited online via social media and patient-support groups. Participants completed the post-traumatic stress disorder (PTSD) Checklist–5 (PCL-5), the United States National Institutes of Health’s Patient-Reported Outcomes Measurement Information System (NIH-PROMIS) –43 profile and demographics. S/SE Asian participants were age and sex matched (1:2) with randomly selected white, non-Hispanic controls. Statistical analyses evaluated differences in IBD-PTS symptoms between groups, the relationship between disease severity and health-related quality of life (HRQoL) and predictors of IBD-PTS severity. Results Forty-seven per cent of the 51 S/SE Asian participants met the diagnostic cut-off for PTSD on the PCL-5 compared to 13.6% of 110 IBD controls. The mean global score on the PCL-5 was three times higher in S/SE Asians. Patients of S/SE Asian decent were over five times more likely to have PTSD due to their IBD experiences than controls, nearly doubling when controlling for disease activity. More severe IBD-PTS was present in S/SE Asian patients with active disease and those with extraintestinal manifestations. Higher global levels of IBD-PTS were associated with poorer HRQoL in S/SE Asians where increased hyperarousal from IBD-PTS predicted more sleep disturbance. Conclusions S/SE Asian patients are five times more likely to experience IBD-PTS than their white, non-Hispanic counterparts. Several cultural factors lead to IBD-PTS in S/SE Asian patients that must be considered by IBD providers. Preventing, screening for and treating IBD-PTS in this population appears warranted. Graphical Abstract

Plants adapt to fluctuating light conditions by a process called non-photochemical quenching (NPQ), where membrane protein PsbS plays a crucial role and transforms a change in the pH-gradient across the thylakoid membrane under excess light conditions into a photoprotective state, leading to de-excitation of antenna chlorophylls. The PsbS activation mechanism is elusive and has been proposed to involve a monomerization step and protonation of specific residues. To elucidate its function, it is essential to produce PsbS in large quantities, stabilize PsbS in a membrane-mimicking environment and analyze its pH-dependent conformational structure. We present an approach for large-scale in-vitro production and spectroscopic characterization of PsbS under controlled, non-crystalline conditions. We produced PsbS of the moss Physcomitrella patens in milligram quantities in E . coli , refolded PsbS in several detergent types and analyzed its conformation at neutral and low pH by Dynamic Light Scattering and NMR spectroscopy. Our results reveal that at both pH conditions, PsbS exist as dimers or in apparent monomer-dimer equilibria. Lowering of the pH induces conformational changes, destabilizes the dimer state and shifts the equilibria towards the monomeric form. In vivo , a similar response upon thylakoid lumen acidification may tune PsbS activity in a gradual manner.